Nature , IF:49.962 , 2022 Sep , V609 (7927) : P575-581 doi: 10.1038/s41586-022-05187-x
ABP1-TMK auxin perception for global phosphorylation and auxin canalization.
Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria. jiri.friml@ista.ac.at.; Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria.; Faculty of Natural Sciences, Institute of Biology, Biotechnology and Environmental Protection, University of Silesia in Katowice, Katowice, Poland.; Laboratory of Biochemistry, Wageningen University, Wageningen, The Netherlands.; Institute for Multidisciplinary Research, University of Belgrade, Belgrade, Serbia.; Department of Plant Biotechnology and Bioinformatics and VIB Center for Plant Systems Biology, Ghent University, Ghent, Belgium.; Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology (CEITEC), Masaryk University, Brno, Czechia.; Graduate School of Science and Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Nagoya, Japan.
The phytohormone auxin triggers transcriptional reprogramming through a well-characterized perception machinery in the nucleus. By contrast, mechanisms that underlie fast effects of auxin, such as the regulation of ion fluxes, rapid phosphorylation of proteins or auxin feedback on its transport, remain unclear(1-3). Whether auxin-binding protein 1 (ABP1) is an auxin receptor has been a source of debate for decades(1,4). Here we show that a fraction of Arabidopsis thaliana ABP1 is secreted and binds auxin specifically at an acidic pH that is typical of the apoplast. ABP1 and its plasma-membrane-localized partner, transmembrane kinase 1 (TMK1), are required for the auxin-induced ultrafast global phospho-response and for downstream processes that include the activation of H(+)-ATPase and accelerated cytoplasmic streaming. abp1 and tmk mutants cannot establish auxin-transporting channels and show defective auxin-induced vasculature formation and regeneration. An ABP1(M2X) variant that lacks the capacity to bind auxin is unable to complement these defects in abp1 mutants. These data indicate that ABP1 is the auxin receptor for TMK1-based cell-surface signalling, which mediates the global phospho-response and auxin canalization.
PMID: 36071161
Nature , IF:49.962 , 2022 Sep , V609 (7927) : P616-621 doi: 10.1038/s41586-022-05142-w
Structures and mechanisms of the Arabidopsis auxin transporter PIN3.
Department of Biophysics and Department of Neurology of the Fourth Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.; Department of Biophysics and Kidney Disease Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.; State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China.; State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, China.; Center of Cryo-Electron Microscopy, Zhejiang University School of Medicine, Hangzhou, China.; Institute of Pesticide and Environmental Toxicology, Zhejiang University, Hangzhou, China.; College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China.; DP Technology, Beijing, China.; Tianjin Key Laboratory of Function and Application of Biological Macromolecular Structures, School of Life Sciences, Tianjin University, Tianjin, China.; Department of Biophysics and Kidney Disease Center, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China. fanyanga@zju.edu.cn.; Alibaba-Zhejiang University Joint Research Center of Future Digital Healthcare, Hangzhou, China. fanyanga@zju.edu.cn.; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Science and Brain-machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China. fanyanga@zju.edu.cn.; State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China. wushan91@hubu.edu.cn.; Department of Biophysics and Department of Neurology of the Fourth Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China. jiangtaoguo@zju.edu.cn.; State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, China. jiangtaoguo@zju.edu.cn.; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Science and Brain-machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China. jiangtaoguo@zju.edu.cn.; Department of Cardiology, Key Laboratory of Cardiovascular Intervention and Regenerative Medicine of Zhejiang Province, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China. jiangtaoguo@zju.edu.cn.; Cancer Center, Zhejiang University, Hangzhou, China. jiangtaoguo@zju.edu.cn.; Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, China. jiangtaoguo@zju.edu.cn.
The PIN-FORMED (PIN) protein family of auxin transporters mediates polar auxin transport and has crucial roles in plant growth and development(1,2). Here we present cryo-electron microscopy structures of PIN3 from Arabidopsis thaliana in the apo state and in complex with its substrate indole-3-acetic acid and the inhibitor N-1-naphthylphthalamic acid (NPA). A. thaliana PIN3 exists as a homodimer, and its transmembrane helices 1, 2 and 7 in the scaffold domain are involved in dimerization. The dimeric PIN3 forms a large, joint extracellular-facing cavity at the dimer interface while each subunit adopts an inward-facing conformation. The structural and functional analyses, along with computational studies, reveal the structural basis for the recognition of indole-3-acetic acid and NPA and elucidate the molecular mechanism of NPA inhibition on PIN-mediated auxin transport. The PIN3 structures support an elevator-like model for the transport of auxin, whereby the transport domains undergo up-down rigid-body motions and the dimerized scaffold domains remain static.
PMID: 35917926
Nature , IF:49.962 , 2022 Sep , V609 (7927) : P611-615 doi: 10.1038/s41586-022-05143-9
Structural insights into auxin recognition and efflux by Arabidopsis PIN1.
The First Affiliated Hospital of USTC, MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.; CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of CAS, Chinese Academy of Sciences (CAS), Shanghai, China.; MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.; Cryo-EM Center, Core Facility Center for Life Sciences, University of Science and Technology of China, Hefei, China.; Institute of Science and Technology Austria (IST Austria), Klosterneuburg, Austria.; The First Affiliated Hospital of USTC, MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China. lx023@ustc.edu.cn.; Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei, China. lx023@ustc.edu.cn.; The First Affiliated Hospital of USTC, MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China. sunlf17@ustc.edu.cn.; Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei, China. sunlf17@ustc.edu.cn.
Polar auxin transport is unique to plants and coordinates their growth and development(1,2). The PIN-FORMED (PIN) auxin transporters exhibit highly asymmetrical localizations at the plasma membrane and drive polar auxin transport(3,4); however, their structures and transport mechanisms remain largely unknown. Here, we report three inward-facing conformation structures of Arabidopsis thaliana PIN1: the apo state, bound to the natural auxin indole-3-acetic acid (IAA), and in complex with the polar auxin transport inhibitor N-1-naphthylphthalamic acid (NPA). The transmembrane domain of PIN1 shares a conserved NhaA fold(5). In the substrate-bound structure, IAA is coordinated by both hydrophobic stacking and hydrogen bonding. NPA competes with IAA for the same site at the intracellular pocket, but with a much higher affinity. These findings inform our understanding of the substrate recognition and transport mechanisms of PINs and set up a framework for future research on directional auxin transport, one of the most crucial processes underlying plant development.
PMID: 35917925
Nature , IF:49.962 , 2022 Sep , V609 (7927) : P605-610 doi: 10.1038/s41586-022-04883-y
Structures and mechanism of the plant PIN-FORMED auxin transporter.
Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.; Plant Systems Biology, School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany.; Skirball Institute of Biomolecular Medicine, Department of Cell Biology, New York University School of Medicine, New York, NY, USA.; Plant Systems Biology, School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany. ulrich.hammes@tum.de.; Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark. bpp@mbg.au.dk.
Auxins are hormones that have central roles and control nearly all aspects of growth and development in plants(1-3). The proteins in the PIN-FORMED (PIN) family (also known as the auxin efflux carrier family) are key participants in this process and control auxin export from the cytosol to the extracellular space(4-9). Owing to a lack of structural and biochemical data, the molecular mechanism of PIN-mediated auxin transport is not understood. Here we present biophysical analysis together with three structures of Arabidopsis thaliana PIN8: two outward-facing conformations with and without auxin, and one inward-facing conformation bound to the herbicide naphthylphthalamic acid. The structure forms a homodimer, with each monomer divided into a transport and scaffold domain with a clearly defined auxin binding site. Next to the binding site, a proline-proline crossover is a pivot point for structural changes associated with transport, which we show to be independent of proton and ion gradients and probably driven by the negative charge of the auxin. The structures and biochemical data reveal an elevator-type transport mechanism reminiscent of bile acid/sodium symporters, bicarbonate/sodium symporters and sodium/proton antiporters. Our results provide a comprehensive molecular model for auxin recognition and transport by PINs, link and expand on a well-known conceptual framework for transport, and explain a central mechanism of polar auxin transport, a core feature of plant physiology, growth and development.
PMID: 35768502
Cell Res , IF:25.617 , 2022 Sep doi: 10.1038/s41422-022-00711-0
A spontaneous thermo-sensitive female sterility mutation in rice enables fully mechanized hybrid breeding.
Department of Biology, Hong Kong Baptist University, Hong Kong, China.; School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, China.; Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, College of Agriculture, Hunan Agricultural University, Changsha, Hunan, China.; Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, CA, USA.; Division of Plant and Microbial Sciences, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 2-1-2 Kannondai Tsukuba, Ibaraki, Japan.; Guangdong Provincial Key Laboratory for Plant Epigenetics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, Guangdong, China.; College of Horticulture Science and Engineering, Shandong Agricultural University, Taian, Shandong, China.; The Rice Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, Guangdong, China.; Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, CA, USA. xuemei.chen@ucr.edu.; Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, College of Agriculture, Hunan Agricultural University, Changsha, Hunan, China. nye@hunau.edu.cn.; Department of Biology, Hong Kong Baptist University, Hong Kong, China. jzhang@hkbu.edu.hk.; School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, China. jzhang@hkbu.edu.hk.; Department of Biology, Hong Kong Baptist University, Hong Kong, China. gqwang@link.cuhk.edu.hk.; School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, China. gqwang@link.cuhk.edu.hk.
Male sterility enables hybrid crop breeding to increase yields and has been extensively studied. But thermo-sensitive female sterility, which is an ideal property that may enable full mechanization in hybrid rice breeding, has rarely been investigated due to the absence of such germplasm. Here we identify the spontaneous thermo-sensitive female sterility 1 (tfs1) mutation that confers complete sterility under regular/high temperature and partial fertility under low temperature as a point mutation in ARGONAUTE7 (AGO7). AGO7 associates with miR390 to form an RNA-Induced Silencing Complex (RISC), which triggers the biogenesis of small interfering RNAs (siRNAs) from TRANS-ACTING3 (TAS3) loci by recruiting SUPPRESSOR OF GENE SILENCING (SGS3) and RNA-DEPENDENT RNA POLYMERASE6 (RDR6) to TAS3 transcripts. These siRNAs are known as tasiR-ARFs as they act in trans to repress auxin response factor genes. The mutant TFS1 (mTFS1) protein is compromised in its ability to load the miR390/miR390* duplex and eject miR390* during RISC formation. Furthermore, tasiR-ARF levels are reduced in tfs1 due to the deficiency in RDR6 but not SGS3 recruitment by mTFS1 RISC under regular/high temperature, while low temperature partially restores mTFS1 function in RDR6 recruitment and tasiR-ARF biogenesis. A miR390 mutant also exhibits female sterility, suggesting that female fertility is controlled by the miR390-AGO7 module. Notably, the tfs1 allele introduced into various elite rice cultivars endows thermo-sensitive female sterility. Moreover, field trials confirm the utility of tfs1 as a restorer line in fully mechanized hybrid rice breeding.
PMID: 36068348
Trends Biotechnol , IF:19.536 , 2022 Sep , V40 (9) : P1019-1020 doi: 10.1016/j.tibtech.2022.06.005
Dynamically regulating metabolic fluxes with synthetic metabolons.
Center for Plant Systems Biology and Biotechnology, 4000 Plovdiv, Bulgaria; Max-Planck-Institute of Molecular Plant Physiology, Am Muhlenberg 1, 14476 Potsdam-Golm, Germany. Electronic address: YOZhang@mpimp-golm.mpg.de.; Center for Plant Systems Biology and Biotechnology, 4000 Plovdiv, Bulgaria; Max-Planck-Institute of Molecular Plant Physiology, Am Muhlenberg 1, 14476 Potsdam-Golm, Germany. Electronic address: fernie@mpimp-golm.mpg.de.
Enzyme-enzyme assemblies commonly occur naturally, yet the factors that lead to their transient nature are not fully understood. Mitkas et al. have shown how clustered regularly interspaced short palindromic repeats (CRISPR) enzymes and RNA scaffolds allow synthetic enzyme complexes to be formed and disassembled as needed, providing powerful new tools for metabolic engineering.
PMID: 35753889
Trends Plant Sci , IF:18.313 , 2022 Aug doi: 10.1016/j.tplants.2022.08.011
Spatiotemporal imaging clarifies leaf primordium patterning.
State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing 100101, China.; State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and Peking-Tsinghua Center for Life Sciences, Center for Quantitative Biology, Peking University, Beijing 100871, China. Electronic address: yuling.jiao@pku.edu.cn.
The first step in organ morphogenesis is the subdivision of a primordium into discrete regions by patterning genes. Recently, Burian et al. used live imaging and cell-lineage tracing to illuminate early patterning events during the establishment of leaf primordium adaxial-abaxial (dorsoventral) polarity, which clarifies controversies in the field.
PMID: 36055917
Nucleic Acids Res , IF:16.971 , 2022 Sep doi: 10.1093/nar/gkac798
Phosphorylation of the auxin signaling transcriptional repressor IAA15 by MPKs is required for the suppression of root development under drought stress in Arabidopsis.
Division of Applied Life Science (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 52828, Republic of Korea.
Since plants are sessile organisms, developmental plasticity in response to environmental stresses is essential for their survival. Upon exposure to drought, lateral root development is suppressed to induce drought tolerance. However, the molecular mechanism by which the development of lateral roots is inhibited by drought is largely unknown. In this study, the auxin signaling repressor IAA15 was identified as a novel substrate of mitogen-activated protein kinases (MPKs) and was shown to suppress lateral root development in response to drought through stabilization by phosphorylation. Both MPK3 and MPK6 directly phosphorylated IAA15 at the Ser-2 and Thr-28 residues. Transgenic plants overexpressing a phospho-mimicking mutant of IAA15 (IAA15DD OX) showed reduced lateral root development due to a higher accumulation of IAA15. In addition, MPK-mediated phosphorylation strongly increased the stability of IAA15 through the inhibition of polyubiquitination. Furthermore, IAA15DD OX plants showed the transcriptional downregulation of two key transcription factors LBD16 and LBD29, responsible for lateral root development. Overall, this study provides the molecular mechanism that explains the significance of the MPK-Aux/IAA module in suppressing lateral root development in response to drought.
PMID: 36161329
Nat Plants , IF:15.793 , 2021 Sep , V8 (9) : P1082-1093 doi: 10.1038/s41477-022-01213-y
PIF4 enhances DNA binding of CDF2 to co-regulate target gene expression and promote Arabidopsis hypocotyl cell elongation.
Department of Plant Developmental Biology, Max Planck Institute for Plant Breeding Research, Cologne, Germany.; Institute of Biochemistry, University of Cologne, Cologne, Germany.; Department of Plant Developmental Biology, Max Planck Institute for Plant Breeding Research, Cologne, Germany. coupland@mpipz.mpg.de.
How specificity is conferred within gene regulatory networks is an important problem in biology. The basic helix-loop-helix PHYTOCHROME-INTERACTING FACTORs (PIFs) and single zinc-finger CYCLING DOF FACTORs (CDFs) mediate growth responses of Arabidopsis to light and temperature. We show that these two classes of transcription factor (TF) act cooperatively. CDF2 and PIF4 are temporally and spatially co-expressed, they interact to form a protein complex and act in the same genetic pathway to promote hypocotyl cell elongation. Furthermore, PIF4 substantially strengthens genome-wide occupancy of CDF2 at a subset of its target genes. One of these, YUCCA8, encodes an auxin biosynthesis enzyme whose transcription is increased by PIF4 and CDF2 to contribute to hypocotyl elongation. The binding sites of PIF4 and CDF2 in YUCCA8 are closely spaced, and in vitro PIF4 enhances binding of CDF2. We propose that this occurs by direct protein interaction and because PIF4 binding alters DNA conformation. Thus, we define mechanisms by which PIF and CDF TFs cooperate to achieve regulatory specificity and promote cell elongation in response to light.
PMID: 35970973
Nat Commun , IF:14.919 , 2022 Sep , V13 (1) : P5147 doi: 10.1038/s41467-022-32888-8
WAVY GROWTH Arabidopsis E3 ubiquitin ligases affect apical PIN sorting decisions.
Department of Applied Genetics and Cell Biology, Institute of Molecular Plant Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190, Wien, Austria.; Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Ghent, Belgium.; , VIB Center for Plant Systems Biology, 9052, Ghent, Belgium.; Institute of Science and Technology Austria (IST Austria), 3400, Klosterneuburg, Austria.; School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China.; Department of Biology, University of Fribourg, Chemin du Musee 10, 1700, Fribourg, Switzerland.; Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojova 263, Praha 6, Czech Republic.; Department of Applied Genetics and Cell Biology, Institute of Molecular Plant Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, 1190, Wien, Austria. christian.luschnig@boku.ac.at.
Directionality in the intercellular transport of the plant hormone auxin is determined by polar plasma membrane localization of PIN-FORMED (PIN) auxin transport proteins. However, apart from PIN phosphorylation at conserved motifs, no further determinants explicitly controlling polar PIN sorting decisions have been identified. Here we present Arabidopsis WAVY GROWTH 3 (WAV3) and closely related RING-finger E3 ubiquitin ligases, whose loss-of-function mutants show a striking apical-to-basal polarity switch in PIN2 localization in root meristem cells. WAV3 E3 ligases function as essential determinants for PIN polarity, acting independently from PINOID/WAG-dependent PIN phosphorylation. They antagonize ectopic deposition of de novo synthesized PIN proteins already immediately following completion of cell division, presumably via preventing PIN sorting into basal, ARF GEF-mediated trafficking. Our findings reveal an involvement of E3 ligases in the selective targeting of apically localized PINs in higher plants.
PMID: 36050482
Nat Commun , IF:14.919 , 2022 Aug , V13 (1) : P4942 doi: 10.1038/s41467-022-32585-6
PIF7 is a master regulator of thermomorphogenesis in shade.
Institute of Plant Sciences, ARO, Volcani Institute, HaMaccabbim Road 68, Rishon LeZion, 7505101, Israel. yogevb@volcani.agri.gov.il.; Howard Hughes Medical Institute, Salk Institute for Biological Studies, La Jolla, CA, 92037, USA. yogevb@volcani.agri.gov.il.; Plant Biology Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA, 92037, USA. yogevb@volcani.agri.gov.il.; Howard Hughes Medical Institute, Salk Institute for Biological Studies, La Jolla, CA, 92037, USA.; Plant Biology Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA, 92037, USA.; Laboratory of Growth Regulators, Faculty of Science, Palacky University and Institute of Experimental Botany, The Czech Academy of Sciences, Slechtitelu 27, CZ-78371, Olomouc, Czech Republic.; Umea Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83, Umea, Sweden.; Howard Hughes Medical Institute, Salk Institute for Biological Studies, La Jolla, CA, 92037, USA. chory@salk.edu.; Plant Biology Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA, 92037, USA. chory@salk.edu.
The size of plant organs is highly responsive to environmental conditions. The plant's embryonic stem, or hypocotyl, displays phenotypic plasticity, in response to light and temperature. The hypocotyl of shade avoiding species elongates to outcompete neighboring plants and secure access to sunlight. Similar elongation occurs in high temperature. However, it is poorly understood how environmental light and temperature cues interact to effect plant growth. We found that shade combined with warm temperature produces a synergistic hypocotyl growth response that dependent on PHYTOCHROME-INTERACTING FACTOR 7 (PIF7) and auxin. This unique but agriculturally relevant scenario was almost totally independent on PIF4 activity. We show that warm temperature is sufficient to promote PIF7 DNA binding but not transcriptional activation and we demonstrate that additional, unknown factor/s must be working downstream of the phyB-PIF-auxin module. Our findings will improve the predictions of how plants will respond to increased ambient temperatures when grown at high density.
PMID: 36038577
Nat Commun , IF:14.919 , 2022 Aug , V13 (1) : P4653 doi: 10.1038/s41467-022-32314-z
Strigolactones are chemoattractants for host tropism in Orobanchaceae parasitic plants.
RIKEN Center for Sustainable Resource Science, Yokohama, 230-0045, Japan.; Division of Biological Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan.; Department of Botany and Plant Sciences, University of California, Riverside, CA, 92521, USA.; PRESTO, Japan Science and Technology Agency, Kawaguchi, Saitama, 332-0012, Japan.; RIKEN Center for Sustainable Resource Science, Yokohama, 230-0045, Japan. ken.shirasu@riken.jp.; Graduate School of Science, The University of Tokyo, Tokyo, 113-0033, Japan. ken.shirasu@riken.jp.
Parasitic plants are worldwide threats that damage major agricultural crops. To initiate infection, parasitic plants have developed the ability to locate hosts and grow towards them. This ability, called host tropism, is critical for parasite survival, but its underlying mechanism remains mostly unresolved. To characterise host tropism, we used the model facultative root parasite Phtheirospermum japonicum, a member of the Orobanchaceae. Here, we show that strigolactones (SLs) function as host-derived chemoattractants. Chemotropism to SLs is also found in Striga hermonthica, a parasitic member of the Orobanchaceae, but not in non-parasites. Intriguingly, chemotropism to SLs in P. japonicum is attenuated in ammonium ion-rich conditions, where SLs are perceived, but the resulting asymmetrical accumulation of the auxin transporter PIN2 is diminished. P. japonicum encodes putative receptors that sense exogenous SLs, whereas expression of a dominant-negative form reduces its chemotropic ability. We propose a function for SLs as navigators for parasite roots.
PMID: 35970835
Genome Biol , IF:13.583 , 2022 Aug , V23 (1) : P181 doi: 10.1186/s13059-022-02750-7
The Arabidopsis APOLO and human UPAT sequence-unrelated long noncoding RNAs can modulate DNA and histone methylation machineries in plants.
Instituto de Agrobiotecnologia del Litoral, CONICET, Universidad Nacional del Litoral, Colectora Ruta Nacional 168 km 0, 3000, Santa Fe, Argentina.; Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Universite Evry, Universite Paris-Saclay, Batiment 630, 91405, Orsay, France.; Institute of Plant Sciences Paris-Saclay IPS2, Universite de Paris, Batiment 630, 91405, Orsay, France.; Institut de Biologie de l'Ecole Normale Superieure (IBENS), Centre National de la Recherche Scientifique (CNRS), Institut National de la Sante et de la Recherche Medicale (INSERM), Ecole Normale Superieure, PSL Research University, 75005, Paris, France.; Instituto de Agrobiotecnologia del Litoral, CONICET, Universidad Nacional del Litoral, Colectora Ruta Nacional 168 km 0, 3000, Santa Fe, Argentina. fariel@santafe-conicet.gov.ar.
BACKGROUND: RNA-DNA hybrid (R-loop)-associated long noncoding RNAs (lncRNAs), including the Arabidopsis lncRNA AUXIN-REGULATED PROMOTER LOOP (APOLO), are emerging as important regulators of three-dimensional chromatin conformation and gene transcriptional activity. RESULTS: Here, we show that in addition to the PRC1-component LIKE HETEROCHROMATIN PROTEIN 1 (LHP1), APOLO interacts with the methylcytosine-binding protein VARIANT IN METHYLATION 1 (VIM1), a conserved homolog of the mammalian DNA methylation regulator UBIQUITIN-LIKE CONTAINING PHD AND RING FINGER DOMAINS 1 (UHRF1). The APOLO-VIM1-LHP1 complex directly regulates the transcription of the auxin biosynthesis gene YUCCA2 by dynamically determining DNA methylation and H3K27me3 deposition over its promoter during the plant thermomorphogenic response. Strikingly, we demonstrate that the lncRNA UHRF1 Protein Associated Transcript (UPAT), a direct interactor of UHRF1 in humans, can be recognized by VIM1 and LHP1 in plant cells, despite the lack of sequence homology between UPAT and APOLO. In addition, we show that increased levels of APOLO or UPAT hamper VIM1 and LHP1 binding to YUCCA2 promoter and globally alter the Arabidopsis transcriptome in a similar manner. CONCLUSIONS: Collectively, our results uncover a new mechanism in which a plant lncRNA coordinates Polycomb action and DNA methylation through the interaction with VIM1, and indicates that evolutionary unrelated lncRNAs with potentially conserved structures may exert similar functions by interacting with homolog partners.
PMID: 36038910
Mol Plant , IF:13.164 , 2022 Sep doi: 10.1016/j.molp.2022.09.004
The protein-protein interaction landscape of transcription factors during gynoecium development in Arabidopsis.
Unidad de Genomica Avanzada (UGA-LANGEBIO), Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional (CINVESTAV-IPN), Irapuato 36824, Guanajuato, Mexico.; Departamento de Biotecnologia y Bioquimica, Unidad Irapuato, CINVESTAV-IPN, Irapuato 36824, Guanajuato, Mexico.; Instituto de Fisica, Universidad de San Luis Potosi. San Luis Potosi 78290, SLP, Mexico.; Unidad de Genomica Avanzada (UGA-LANGEBIO), Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional (CINVESTAV-IPN), Irapuato 36824, Guanajuato, Mexico. Electronic address: stefan.defolter@cinvestav.mx.
Flowers are composed of organs whose identity is defined by the combinatorial activity of transcription factors (TFs). The interactions between MADS-box TFs and protein complex formation have been schematized in the floral quartet model of flower development. The gynoecium is the flower's female reproductive part, crucial for fruit and seed production and, hence, for reproductive success. After the establishment of carpel identity, many tissues arise to form a mature gynoecium. TFs have been described as regulators of gynoecium development, and some interactions and complexes have been identified. However, broad knowledge about the interactions among these TFs and their participation during development remains scarce. This work used a systems biology approach to understand the formation of a complex reproductive unit - as the gynoecium - by mapping binary interactions between well-characterised TFs. We analysed almost 4,500 combinations and detected more than 250 protein-protein interactions (PPIs), resulting in a process-specific interaction map. Topological analyses suggest hidden functions and novel roles for many TFs. Additionally, we observed a close relationship between TFs involved in auxin and cytokinin signalling pathways and other TFs. Furthermore, we analysed the network by combining PPI data, expression, and genetic data, which helped us to dissect it into several dynamic spatio-temporal subnetworks related to gynoecium development processes. Finally, we generated an extended PPI network that predicts new players in gynoecium development. All the results serve as a valuable resource for the plant community.
PMID: 36088536
Mol Plant , IF:13.164 , 2022 Aug doi: 10.1016/j.molp.2022.08.008
The regeneration factors ERF114 and ERF115 regulate auxin-mediated lateral root development in response to mechanical cues.
Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent B-9052, Belgium; VIB Center for Plant Systems Biology, Ghent B-9052, Belgium.; Department of Plant Biology, Linnean Center for Plant Biology, Swedish University of Agricultural Sciences, Almas alle 5, 756 51 Uppsala, Sweden.; Department of Plant Biochemistry, Center for Plant Molecular Biology (ZMBP), University of Tubingen, 72076 Tubingen, Germany.; Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent B-9052, Belgium; VIB Center for Plant Systems Biology, Ghent B-9052, Belgium. Electronic address: lieven.deveylder@psb.vib-ugent.be.
Plants show an unparalleled regenerative capacity, allowing them to survive severe stress conditions, such as injury, herbivory attack, and harsh weather conditions. This potential not only replenishes tissues and restores damaged organs but can also give rise to whole plant bodies. Despite the intertwined nature of development and regeneration, common upstream cues and signaling mechanisms are largely unknown. Here, we demonstrate that in addition to being activators of regeneration, ETHYLENE RESPONSE FACTOR 114 (ERF114) and ERF115 govern developmental growth in the absence of wounding or injury. Increased ERF114 and ERF115 activity enhances auxin sensitivity, which is correlated with enhanced xylem maturation and lateral root formation, whereas their knockout results in a decrease in lateral roots. Moreover, we provide evidence that mechanical cues contribute to ERF114 and ERF115 expression in correlation with BZR1-mediated brassinosteroid signaling under both regenerative and developmental conditions. Antagonistically, cell wall integrity surveillance via mechanosensory FERONIA signaling suppresses their expression under both conditions. Taken together, our data suggest a molecular framework in which cell wall signals and mechanical strains regulate organ development and regenerative responses via ERF114- and ERF115-mediated auxin signaling.
PMID: 36030378
Dev Cell , IF:12.27 , 2022 Sep , V57 (17) : P2063-2080.e10 doi: 10.1016/j.devcel.2022.07.017
Mechanical conflict caused by a cell-wall-loosening enzyme activates de novo shoot regeneration.
Indian Institute of Science Education and Research (IISER), Pune 411008, India; IISER, Thiruvananthapuram 695551, India.; Indian Institute of Science Education and Research (IISER), Pune 411008, India; IISER, Thiruvananthapuram 695551, India. Electronic address: mabel.m.mathew@gmail.com.; IISER, Thiruvananthapuram 695551, India.; Indian Institute of Science Education and Research (IISER), Pune 411008, India.; Laboratory of Biochemistry, Wageningen University, Wageningen 6708WE, The Netherlands.; Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki 00014, Finland; Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, Viikki Plant Science Centre, University of Helsinki, Helsinki 00014, Finland.; School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia.; Indian Institute of Science Education and Research (IISER), Pune 411008, India; IISER, Thiruvananthapuram 695551, India. Electronic address: kalika.prasad@iiserpune.ac.in.
Cellular heterogeneity is a hallmark of multicellular organisms. During shoot regeneration from undifferentiated callus, only a select few cells, called progenitors, develop into shoot. How these cells are selected and what governs their subsequent progression to a patterned organ system is unknown. Using Arabidopsis thaliana, we show that it is not just the abundance of stem cell regulators but rather the localization pattern of polarity proteins that predicts the progenitor's fate. A shoot-promoting factor, CUC2, activated the expression of the cell-wall-loosening enzyme, XTH9, solely in a shell of cells surrounding the progenitor, causing different mechanical stresses in these cells. This mechanical conflict then activates cell polarity in progenitors to promote meristem formation. Interestingly, genetic or physical perturbations to cells surrounding the progenitor impaired the progenitor and vice versa. These suggest a feedback loop between progenitors and their neighbors for shoot regeneration in the absence of tissue-patterning cues.
PMID: 36002002
EMBO J , IF:11.598 , 2022 Aug : Pe110988 doi: 10.15252/embj.2022110988
ARF2-PIF5 interaction controls transcriptional reprogramming in the ABS3-mediated plant senescence pathway.
State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, China.; Department of Molecular Biology and Centre for Computational and Integrative Biology, Massachusetts General Hospital, Boston, MA, USA.; Department of Genetics, Harvard Medical School, Boston, MA, USA.; Institute of Future Agriculture, Northwest A&F University, Yangling, China.
One of the hallmarks of plant senescence is the global transcriptional reprogramming coordinated by a plethora of transcription factors (TFs). However, mechanisms underlying the interactions between different TFs in modulating senescence remain obscure. Previously, we discovered that plant ABS3 subfamily MATE transporter genes regulate senescence and senescence-associated transcriptional changes. In a genetic screen for mutants suppressing the accelerated senescence phenotype of the gain-of-function mutant abs3-1D, AUXIN RESPONSE FACTOR 2 (ARF2) and PHYTOCHROME-INTERACTING FACTOR 5 (PIF5) were identified as key TFs responsible for transcriptional regulation in the ABS3-mediated senescence pathway. ARF2 and PIF5 (as well as PIF4) interact directly and function interdependently to promote senescence, and they share common target genes such as key senescence promoting genes ORESARA 1 (ORE1) and STAY-GREEN 1 (SGR1) in the ABS3-mediated senescence pathway. In addition, we discovered reciprocal regulation between ABS3-subfamily MATEs and the ARF2 and PIF5/4 TFs. Taken together, our findings reveal a regulatory paradigm in which the ARF2-PIF5/4 functional module facilitates the transcriptional reprogramming in the ABS3-mediated senescence pathway.
PMID: 35942625
Plant Cell , IF:11.277 , 2022 Aug doi: 10.1093/plcell/koac266
Localization of PHRAGMOPLAST ORIENTING KINESIN1 at the division site depends on the microtubule binding proteins TANGLED1 and AUXIN-INDUCED IN ROOT CULTURES9 in Arabidopsis.
Graduate Group in Biochemistry and Molecular Biology.; Department of Botany and Plant Sciences, Center for Plant Cell Biology, Institute of Integrative Genome Biology, University of California, Riverside.
Proper plant growth and development requires spatial coordination of cell divisions. Two unrelated microtubule-binding proteins, TANGLED1 (TAN1) and AUXIN-INDUCED IN ROOT CULTURES9 (AIR9), are together required for normal growth and division-plane orientation in Arabidopsis (Arabidopsis thaliana). The tan1 air9 double mutant has synthetic growth and division-plane orientation defects while single mutants lack obvious defects. Here we show that the division site-localized protein, PHRAGMOPLAST ORIENTING KINESIN1 (POK1), was aberrantly lost from the division site during metaphase and telophase in the tan1 air9 mutant. Since TAN1 and POK1 interact via the first 132 amino acids of TAN1 (TAN11-132), we assessed the localization and function of TAN11-132 in the tan1 air9 double mutant. TAN11-132 rescued tan1 air9 mutant phenotypes and localized to the division site during telophase. However, replacing six amino-acid residues within TAN11-132, which disrupted the POK1-TAN1 interaction in the yeast-two-hybrid system, caused loss of both rescue and division-site localization of TAN11-132 in the tan1 air9 mutant. Full-length TAN1 with the same alanine substitutions had defects in phragmoplast guidance and reduced TAN1 and POK1 localization at the division site but rescued most tan1 air9 mutant phenotypes. Together, these data suggest that TAN1 and AIR9 are required for POK1 localization, and yet unknown proteins may stabilize TAN1-POK1 interactions.
PMID: 36005863
Plant Cell , IF:11.277 , 2022 Aug doi: 10.1093/plcell/koac262
Auxin and abscisic acid antagonistically regulate ascorbic acid production via the SlMAPK8-SlARF4-SlMYB11 module in tomato.
Key Laboratory of Plant Hormones and Development Regulation of Chongqing, School of Life Sciences, Chongqing University, Chongqing 400044, China.; College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China.
Ascorbic acid (AsA) is a multifunctional phytonutrient that is essential for the human diet as well as plant development. While much is known about AsA biosynthesis in plants, how this process is regulated in tomato (Solanum lycopersicum) fruits remains unclear. Here we found that auxin treatment inhibited AsA accumulation in the leaves and pericarps of tomato. The auxin response factor gene SlARF4 is induced by auxin to mediate auxin-induced inhibition of AsA accumulation. Specifically, SlARF4 transcriptionally inhibits the transcription factor gene SlMYB11, thereby modulating AsA accumulation by regulating the transcription of the AsA biosynthesis genes L-galactose-1-phosphate phosphatase (GPP), L-galactono-1,4-lactone dehydrogenase (GLDH), and dehydroascorbate (DHAR). By contrast, abscisic acid (ABA) treatment increased AsA accumulation in tomato under drought stress. ABA induced the expression of the mitogen-activated protein kinase gene SlMAPK8. We demonstrate that SlMAPK8 phosphorylates SlARF4 and inhibits its transcriptional activity, whereas SlMAPK8 phosphorylates SlMYB11 and activates its transcriptional activity. SlMAPK8 functions in ABA-induced AsA accumulation and drought stress tolerance. Moreover, ABA antagonizes the effects of auxin on AsA biosynthesis. Therefore, auxin- and ABA-induced regulation of AsA accumulation is mediated by the SlMAPK8-SlARF4-SlMYB11 module in tomato during fruit development and drought stress responses, shedding light on the roles of phytohormones in regulating AsA accumulation to mediate stress tolerance.
PMID: 36000899
Plant Cell , IF:11.277 , 2022 Aug doi: 10.1093/plcell/koac258
A case of identity: Activation of auxin biosynthesis drives cell reprogramming.
Assistant Features Editor, The Plant Cell, American Society of Plant Biologists, USA.; Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, UK.
PMID: 35977390
Plant Cell , IF:11.277 , 2022 Aug doi: 10.1093/plcell/koac254
A SlCLV3-SlWUS module regulates auxin and ethylene homeostasis in low light-induced tomato flower abscission.
College of Horticulture, Shenyang Agricultural University, Shenyang, Liaoning 110866, China.; Key Laboratory of Protected Horticulture of Ministry of Education, Shenyang, Liaoning Province, China.; Crops Pathology and Genetic Research Unit, United States Department of Agriculture Agricultural Research Service, California 95616, USA.; Department of Plant Sciences, University of California, California 95616, USA.
Premature abscission of flowers and fruits triggered by low light stress can severely reduce crop yields. However, the underlying molecular mechanism of this organ abscission is not fully understood. Here, we show that a gene (SlCLV3) encoding CLAVATA3 (CLV3), a peptide hormone that regulates stem cell fate in meristems, is highly expressed in the pedicel abscission zone (AZ) in response to low light in tomato (Solanum lycopersicum). SlCLV3 knockdown and knockout lines exhibit delayed low light-induced flower drop. The receptor kinases SlCLV1 and BARELY ANY MERISTEM1 (SlBAM1) function in the SlCLV3 peptide-induced low light response in the AZ to decrease expression of the transcription factor gene WUSCHEL (SlWUS). DNA affinity purification sequencing identified the transcription factor genes KNOX-LIKE HOMEDOMAIN PROTEIN1 (SlKD1) and FRUITFULL2 (SlFUL2) as SlWUS target genes. Our data reveal that low light reduces SlWUS expression, resulting in higher SlKD1 and SlFUL2 expression in the AZ, thereby perturbing the auxin response gradient and causing increased ethylene production, eventually leading to the initiation of abscission. These results demonstrate that the SlCLV3-SlWUS signaling pathway plays a central role in low light-induced abscission by affecting auxin and ethylene homeostasis.
PMID: 35972422
Plant Cell , IF:11.277 , 2022 Aug doi: 10.1093/plcell/koac250
Rice EIL1 interacts with OsIAAs to regulate auxin biosynthesis mediated by the tryptophan aminotransferase MHZ10/OsTAR2 during root ethylene responses.
State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, 100101, China.; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.; College of Agriculture, South China Agricultural University, Guangzhou 510642, China.; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China.
Ethylene plays essential roles in adaptive growth of rice (Oryza sativa). Understanding of the crosstalk between ethylene and auxin is limited in rice. Here, from an analysis of the root-specific ethylene-insensitive rice mutant mao hu zi 10 (mhz10), we identified the tryptophan aminotransferase (TAR) MHZ10/OsTAR2, which catalyzes the key step in indole-3-pyruvic acid-dependent auxin biosynthesis. Genetically, OsTAR2 acts downstream of ethylene signaling in root ethylene responses. OsEIL1 directly activated OsTAR2 expression. Surprisingly, ethylene induction of OsTAR2 expression still required the auxin pathway. We also show that OsIAA1/9 and OsIAA21/31 physically interact with OsEIL1 and show promotive and repressive effects on OsEIL1-activated OsTAR2 promoter activity, respectively. These effects likely depend on their EAR motif-mediated histone acetylation/deacetylation modification. The special promoting activity of OsIAA1/9 on OsEIL1 may require both the EAR motifs and the flanking sequences for recruitment of histone acetyltransferase. The repressors OsIAA21/31 exhibit earlier degradation upon ethylene treatment than the activators OsIAA1/9 in a TIR1/AFB-dependent manner, allowing OsEIL1 activation by activators OsIAA1/9 for OsTAR2 expression and signal amplification. This study reveals a positive feedback regulation of ethylene signaling by auxin biosynthesis and highlights the crosstalk between ethylene and auxin pathways at a previously underappreciated level for root growth regulation in rice.
PMID: 35972379
Plant Cell , IF:11.277 , 2022 Aug doi: 10.1093/plcell/koac218
Transcriptional activation of auxin biosynthesis drives developmental reprogramming of differentiated cells.
Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.; Center for Sustainable Resource Science, RIKEN, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan.; Department of Biological Chemistry, College of Bioscience and Biotechnology, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi 487-8501, Japan.; Division of Evolutionary Biology, National Institute for Basic Biology, Okazaki, Aichi 444-8585, Japan.; Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies, SOKENDAI, Okazaki, Aichi 444-8585, Japan.; Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent B-9052, Belgium.; VIB Center for Plant Systems Biology, Ghent B-9052, Belgium.
Plant cells exhibit remarkable plasticity of their differentiation states, enabling regeneration of whole plants from differentiated somatic cells. How they revert cell fate and express pluripotency, however, remains unclear. In this study we demonstrate that transcriptional activation of auxin biosynthesis is crucial for reprogramming differentiated Arabidopsis (Arabidopsis thaliana) leaf cells. Our data show that interfering with the activity of histone acetyltransferases dramatically reduces callus formation from leaf mesophyll protoplasts. Histone acetylation permits transcriptional activation of PLETHORAs (PLTs), leading to the induction of their downstream YUCCA1 (YUC1) gene encoding an enzyme for auxin biosynthesis. Auxin biosynthesis is in turn required to accomplish initial cell division through the activation of G2/M phase genes mediated by MYB DOMAIN PROTEIN 3-RELATED (MYB3Rs). We further show that the AUXIN RESPONSE FACTOR 7 (ARF7)/ARF19 and INDOLE-3-ACETIC ACID INDUCIBLE 3 (IAA3)/IAA18-mediated auxin signaling pathway is responsible for cell cycle reactivation by transcriptionally upregulating MYB3R4. These findings provide a mechanistic model of how differentiated plant cells revert their fate and reinitiate the cell cycle to become pluripotent.
PMID: 35922895
Plant Cell , IF:11.277 , 2022 Aug , V34 (9) : P3151-3153 doi: 10.1093/plcell/koac175
From the archives: Polar auxin transport in nodule development, DNA replication timing, and developmentally light-regulated genes.
Assistant Features Editor, The Plant Cell, American Society of Plant Biologists, USA.; Department of Plant Biotechnology and Bioinformatics, Ghent University, Belgium.; Center for Plant Systems Biology, VIB, Belgium.
PMID: 35770820
Plant Cell , IF:11.277 , 2022 Sep , V34 (10) : P3577-3610 doi: 10.1093/plcell/koac193
Rapid growth of Moso bamboo (Phyllostachys edulis): Cellular roadmaps, transcriptome dynamics, and environmental factors.
Co-Innovation Center for Sustainable Forestry in Southern China, Bamboo Research Institute, Key Laboratory of National Forestry and Grassland Administration on Subtropical Forest Biodiversity Conservation, College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu 210037, China.; Boyce Thompson Institute, Cornell University, Ithaca, New York 14853, USA.; Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India.; Key Laboratory of National Forestry and Grassland Administration, Beijing for Bamboo & Rattan Science and Technology, Institute of Gene Science and Industrialization for Bamboo and Rattan Resources, International Center for Bamboo and Rattan, Beijing 100102, China.; Jiangxi Provincial Key Laboratory for Bamboo Germplasm Resources and Utilization, Jiangxi Agriculture University, Nanchang, Jiangxi 330045, China.; State Key Laboratory of Genetic Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200433, China.
Moso bamboo (Phyllostachys edulis) shows remarkably rapid growth (114.5 cm/day), but the underlying biological mechanisms remain unclear. After examining more than 12,750 internodes from more than 510 culms from 17 Moso populations, we identified internode 18 as a representative internode for rapid growth. This internode includes a 2-cm cell division zone (DZ), a cell elongation zone up to 12 cm, and a secondary cell wall (SCW) thickening zone. These zones elongated 11.8 cm, produced approximately 570,000,000 cells, and deposited approximately 28 mg g-1 dry weight (DW) lignin and approximately 44 mg g-1 DW cellulose daily, far exceeding vegetative growth observed in other plants. We used anatomical, mathematical, physiological, and genomic data to characterize development and transcriptional networks during rapid growth in internode 18. Our results suggest that (1) gibberellin may directly trigger the rapid growth of Moso shoots, (2) decreased cytokinin and increased auxin accumulation may trigger cell DZ elongation, and (3) abscisic acid and mechanical pressure may stimulate rapid SCW thickening via MYB83L. We conclude that internode length involves a possible tradeoff mediated by mechanical pressure caused by rapid growth, possibly influenced by environmental temperature and regulated by genes related to cell division and elongation. Our results provide insight into the rapid growth of Moso bamboo.
PMID: 35766883
Plant Cell , IF:11.277 , 2022 Aug , V34 (9) : P3200-3213 doi: 10.1093/plcell/koac179
On the trail of auxin: Reporters and sensors.
CEITEC MU-Central European Institute of Technology, Masaryk University, Brno, Czech Republic.; Faculty of Science, National Centre for Biomolecular Research, Masaryk University, Brno, Czech Republic.
The phytohormone auxin is a master regulator of plant growth and development in response to many endogenous and environmental signals. The underlying coordination of growth is mediated by the formation of auxin maxima and concentration gradients. The visualization of auxin dynamics and distribution can therefore provide essential information to increase our understanding of the mechanisms by which auxin orchestrates these growth and developmental processes. Several auxin reporters have been developed to better perceive the auxin distribution and signaling machinery in vivo. This review focuses on different types of auxin reporters and biosensors used to monitor auxin distribution and its dynamics, as well as auxin signaling, at the cellular and tissue levels in different plant species. We provide a brief history of each reporter and biosensor group and explain their principles and utilities.
PMID: 35708654
Plant Cell , IF:11.277 , 2022 Aug , V34 (9) : P3460-3481 doi: 10.1093/plcell/koac177
The retrograde signaling regulator ANAC017 recruits the MKK9-MPK3/6, ethylene, and auxin signaling pathways to balance mitochondrial dysfunction with growth.
Department of Animal, Plant and Soil Science, La Trobe University, Bundoora, Victoria 3086, Australia.; ARC Centre of Excellence in Plant Energy Biology, La Trobe University, Bundoora, Victoria 3086, Australia.
In plant cells, mitochondria are ideally positioned to sense and balance changes in energy metabolism in response to changing environmental conditions. Retrograde signaling from mitochondria to the nucleus is crucial for adjusting the required transcriptional responses. We show that ANAC017, the master regulator of mitochondrial stress, directly recruits a signaling cascade involving the plant hormones ethylene and auxin as well as the MAP KINASE KINASE (MKK) 9-MAP KINASE (MPK) 3/6 pathway in Arabidopsis thaliana. Chromatin immunoprecipitation followed by sequencing and overexpression demonstrated that ANAC017 directly regulates several genes of the ethylene and auxin pathways, including MKK9, 1-AMINO-CYCLOPROPANE-1-CARBOXYLATE SYNTHASE 2, and YUCCA 5, in addition to genes encoding transcription factors regulating plant growth and stress responses such as BASIC REGION/LEUCINE ZIPPER MOTIF (bZIP) 60, bZIP53, ANAC081/ATAF2, and RADICAL-INDUCED CELL DEATH1. A time-resolved RNA-seq experiment established that ethylene signaling precedes the stimulation of auxin signaling in the mitochondrial stress response, with a large part of the transcriptional regulation dependent on ETHYLENE-INSENSITIVE 3. These results were confirmed by mutant analyses. Our findings identify the molecular components controlled by ANAC017, which integrates the primary stress responses to mitochondrial dysfunction with whole plant growth via the activation of regulatory and partly antagonistic feedback loops.
PMID: 35708648
Plant Cell , IF:11.277 , 2022 Aug , V34 (9) : P3280-3300 doi: 10.1093/plcell/koac146
A molecular framework of ethylene-mediated fruit growth and ripening processes in tomato.
Department of Biology,Institute of Plant and Food Science, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China.; Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China.; Key Laboratory of Plant Hormones and Development Regulation of Chongqing, School of Life Sciences, Chongqing University, Chongqing 401331, China.; Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China.
Although the role of ethylene in tomato (Solanum lycopersicum) fruit ripening has been intensively studied, its role in tomato fruit growth remains poorly understood. In addition, the relationship between ethylene and the developmental factors NON-RIPENING (NOR) and RIPENING INHIBITOR (RIN) during ripening is under debate. Here, we carried out comprehensive genetic analyses of genome-edited mutants of tomato ETHYLENE INSENSITIVE 2 (SlEIN2), four EIN3-like genes (SlEIL1-4), and three EIN3 BINDING F-box protein genes (SlEBF1-3). Both slein2-1 and the high-order sleil mutant (sleil1 sleil2 sleil3/SlEIL3 sleil4) showed reduced fruit size, mainly due to decreased auxin biosynthesis. During fruit maturation, slein2 mutants displayed the complete cessation of ripening, which was partially rescued by slebf1 but not slebf2 or slebf3. We also discovered that ethylene directly activates the expression of the developmental genes NOR, RIN, and FRUITFULL1 (FUL1) via SlEIL proteins. Indeed, overexpressing these genes partially rescued the ripening defects of slein2-1. Finally, the signal intensity of the ethylene burst during fruit maturation was intimately connected with the progression of full ripeness. Collectively, our work uncovers a critical role of ethylene in fruit growth and supports a molecular framework of ripening control in which the developmental factors NOR, RIN, and FUL1 act downstream of ethylene signaling.
PMID: 35604102
Proc Natl Acad Sci U S A , IF:11.205 , 2022 Oct , V119 (40) : Pe2205757119 doi: 10.1073/pnas.2205757119
Modulation of receptor-like transmembrane kinase 1 nuclear localization by DA1 peptidases in Arabidopsis.
Department of Cell and Developmental Biology, John Innes Centre, Norwich NR4 7UH, United Kingdom.; State Key Laboratory of Plant Cell and Chromosome Engineering, CAS Centre for Excellence in Molecular Plant Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.; University of Chinese Academy of Sciences, Beijing 100039, China.
The cleavage of intracellular domains of receptor-like kinases (RLKs) has an important functional role in the transduction of signals from the cell surface to the nucleus in many organisms. However, the peptidases that catalyze protein cleavage during signal transduction remain poorly understood despite their crucial roles in diverse signaling processes. Here, we report in the flowering plant Arabidopsis thaliana that members of the DA1 family of ubiquitin-regulated Zn metallopeptidases cleave the cytoplasmic kinase domain of transmembrane kinase 1 (TMK1), releasing it for nuclear localization where it represses auxin-responsive cell growth during apical hook formation by phosphorylation and stabilization of the transcriptional repressors IAA32 and IAA34. Mutations in DA1 family members exhibited reduced apical hook formation, and DA1 family-mediated cleavage of TMK1 was promoted by auxin treatment. Expression of the DA1 family-generated intracellular kinase domain of TMK1 by an auxin-responsive promoter fully restored apical hook formation in a tmk1 mutant, establishing the function of DA1 family peptidase activities in TMK1-mediated differential cell growth and apical hook formation. DA1 family peptidase activity therefore modulates TMK1 kinase activity between a membrane location where it stimulates acid cell growth and initiates an auxin-dependent kinase cascade controlling cell proliferation in lateral roots and a nuclear localization where it represses auxin-mediated gene expression and growth.
PMID: 36161927
Proc Natl Acad Sci U S A , IF:11.205 , 2022 Sep , V119 (39) : Pe2209717119 doi: 10.1073/pnas.2209717119
The CsHEC1-CsOVATE module contributes to fruit neck length variation via modulating auxin biosynthesis in cucumber.
State Key Laboratory of Agrobiotechnology, Joint International Research Laboratory of Crop Molecular Breeding, Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, Department of Vegetable Sciences, China Agricultural University, Beijing 100193, China.; College of Horticulture Science and Technology, Hebei Normal University of Science and Technology, Qinhuangdao 066004, China.
Fruit neck is the proximal portion of the fruit with undesirable taste that has detrimental effects on fruit shape and commercial value in cucumber. Despite the dramatic variations in fruit neck length of cucumber germplasms, the genes and regulatory mechanisms underlying fruit neck elongation remain mysterious. In this study, we found that Cucumis sativus HECATE1 (CsHEC1) was highly expressed in fruit neck. Knockout of CsHEC1 resulted in shortened fruit neck and decreased auxin accumulation, whereas overexpression of CsHEC1 displayed the opposite effects, suggesting that CsHEC1 positively regulated fruit neck length by modulating local auxin level. Further analysis showed that CsHEC1 directly bound to the promoter of the auxin biosynthesis gene YUCCA4 (CsYUC4) and activated its expression. Enhanced expression of CsYUC4 resulted in elongated fruit neck and elevated auxin content. Moreover, knockout of CsOVATE resulted in longer fruit neck and higher auxin. Genetic and biochemical data showed that CsOVATE physically interacted with CsHEC1 to antagonize its function by attenuating the CsHEC1-mediated CsYUC4 transcriptional activation. In cucumber germplasms, the expression of CsHEC1 and CsYUC4 positively correlated with fruit neck length, while that of CsOVATE showed a negative correlation. Together, our results revealed a CsHEC1-CsOVATE regulatory module that confers fruit neck length variation via CsYUC4-mediated auxin biosynthesis in cucumber.
PMID: 36122223
Proc Natl Acad Sci U S A , IF:11.205 , 2022 Sep , V119 (36) : Pe2121671119 doi: 10.1073/pnas.2121671119
Auxin regulates source-sink carbohydrate partitioning and reproductive organ development in rice.
National Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China.; National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, Huazhong Agricultural University, Wuhan 430070, China.; National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Carbohydrate partitioning between the source and sink tissues plays an important role in regulating plant growth and development. However, the molecular mechanisms regulating this process remain poorly understood. In this study, we show that elevated auxin levels in the rice dao mutant cause increased accumulation of sucrose in the photosynthetic leaves but reduced sucrose content in the reproductive organs (particularly in the lodicules, anthers, and ovaries), leading to closed spikelets, indehiscent anthers, and parthenocarpic seeds. RNA sequencing analysis revealed that the expression of AUXIN RESPONSE FACTOR 18 (OsARF18) and OsARF2 is significantly up- and down-regulated, respectively, in the lodicule of dao mutant. Overexpression of OsARF18 or knocking out of OsARF2 phenocopies the dao mutant. We demonstrate that OsARF2 regulates the expression of OsSUT1 through direct binding to the sugar-responsive elements (SuREs) in the OsSUT1 promoter and that OsARF18 represses the expression of OsARF2 and OsSUT1 via direct binding to the auxin-responsive element (AuxRE) or SuRE in their promoters, respectively. Furthermore, overexpression of OsSUT1 in the dao and Osarf2 mutant backgrounds could largely rescue the spikelets' opening and seed-setting defects. Collectively, our results reveal an auxin signaling cascade regulating source-sink carbohydrate partitioning and reproductive organ development in rice.
PMID: 36037381
Proc Natl Acad Sci U S A , IF:11.205 , 2022 Aug , V119 (35) : Pe2208795119 doi: 10.1073/pnas.2208795119
Regulators of early maize leaf development inferred from transcriptomes of laser capture microdissection (LCM)-isolated embryonic leaf cells.
Biodiversity Research Center, Academia Sinica, Taipei 115, Taiwan.; Department of Plant Biology, Michigan State University, East Lansing, MI 48824.; Department of Computational Mathematics, Science, and Engineering, Michigan State University, East Lansing, MI 48824.; Department of Bioagricultural Science, National Chiayi University, Chiayi 600, Taiwan.; School of Biological Sciences, Washington State University, Pullman, WA 99164.; Institute of Plant and Microbial Biology, Academia Sinica, Taipei 115, Taiwan.; Department of Ecology and Evolution, University of Chicago, Chicago, IL 60637.
The superior photosynthetic efficiency of C4 leaves over C3 leaves is owing to their unique Kranz anatomy, in which the vein is surrounded by one layer of bundle sheath (BS) cells and one layer of mesophyll (M) cells. Kranz anatomy development starts from three contiguous ground meristem (GM) cells, but its regulators and underlying molecular mechanism are largely unknown. To identify the regulators, we obtained the transcriptomes of 11 maize embryonic leaf cell types from five stages of pre-Kranz cells starting from median GM cells and six stages of pre-M cells starting from undifferentiated cells. Principal component and clustering analyses of transcriptomic data revealed rapid pre-Kranz cell differentiation in the first two stages but slow differentiation in the last three stages, suggesting early Kranz cell fate determination. In contrast, pre-M cells exhibit a more prolonged transcriptional differentiation process. Differential gene expression and coexpression analyses identified gene coexpression modules, one of which included 3 auxin transporter and 18 transcription factor (TF) genes, including known regulators of Kranz anatomy and/or vascular development. In situ hybridization of 11 TF genes validated their expression in early Kranz development. We determined the binding motifs of 15 TFs, predicted TF target gene relationships among the 18 TF and 3 auxin transporter genes, and validated 67 predictions by electrophoresis mobility shift assay. From these data, we constructed a gene regulatory network for Kranz development. Our study sheds light on the regulation of early maize leaf development and provides candidate leaf development regulators for future study.
PMID: 36001691
Proc Natl Acad Sci U S A , IF:11.205 , 2022 Aug , V119 (32) : Pe2206869119 doi: 10.1073/pnas.2206869119
Chemical inhibition of the auxin inactivation pathway uncovers the roles of metabolic turnover in auxin homeostasis.
Department of Bioscience, Okayama University of Science, Okayama 700-0005, Japan.; Department of Biochemistry, Okayama University of Science, Okayama 700-0005, Japan.; Department of Biological Production Science, United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Fuchu 183-8509, Japan.; Department of Biology, Washington University in St. Louis, St. Louis, MO 63130.; School of Life Sciences, University of Warwick, Coventry CV4 7AS, United Kingdom.; Section of Cell and Developmental Biology, University of California San Diego, La Jolla, CA 92093.; Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Fuchu 183-8509, Japan.; RIKEN Center for Sustainable Resource Science, Kanagawa 230-0045, Japan.
The phytohormone auxin, indole-3-acetic acid (IAA), plays a prominent role in plant development. Auxin homeostasis is coordinately regulated by auxin synthesis, transport, and inactivation; however, the physiological contribution of auxin inactivation to auxin homeostasis has not been determined. The GH3 IAA-amino acid conjugating enzymes play a central role in auxin inactivation. Chemical inhibition of GH3 proteins in planta is challenging because the inhibition of these enzymes leads to IAA overaccumulation that rapidly induces GH3 expression. Here, we report the characterization of a potent GH3 inhibitor, kakeimide, that selectively targets IAA-conjugating GH3 proteins. Chemical knockdown of the auxin inactivation pathway demonstrates that auxin turnover is very rapid (about 10 min) and indicates that both auxin biosynthesis and inactivation dynamically regulate auxin homeostasis.
PMID: 35914172
Proc Natl Acad Sci U S A , IF:11.205 , 2022 Aug , V119 (31) : Pe2122460119 doi: 10.1073/pnas.2122460119
Molecular framework integrating nitrate sensing in root and auxin-guided shoot adaptive responses.
Institute of Science and Technology Austria, Klosterneuburg, 3400 Austria.; Laboratory of Growth Regulators, Faculty of Science, Palacky University and Institute of Experimental Botany, The Czech Academy of Sciences, Olomouc, 78371,Czech Republic.; Institute for Plant Sciences of Montpellier (IPSiM), CNRS, National Research Institute for Agriculture, Food and the Environment (INRAE), Institut Agro, Universite Montpellier, Montpellier, 34060, France.; Institut Jean-Pierre Bourgin, National Research Institute for Agriculture, Food and the Environment (INRAE), AgroParisTech, Universite Paris-Saclay, Versailles, 78000, France.
Mineral nutrition is one of the key environmental factors determining plant development and growth. Nitrate is the major form of macronutrient nitrogen that plants take up from the soil. Fluctuating availability or deficiency of this element severely limits plant growth and negatively affects crop production in the agricultural system. To cope with the heterogeneity of nitrate distribution in soil, plants evolved a complex regulatory mechanism that allows rapid adjustment of physiological and developmental processes to the status of this nutrient. The root, as a major exploitation organ that controls the uptake of nitrate to the plant body, acts as a regulatory hub that, according to nitrate availability, coordinates the growth and development of other plant organs. Here, we identified a regulatory framework, where cytokinin response factors (CRFs) play a central role as a molecular readout of the nitrate status in roots to guide shoot adaptive developmental response. We show that nitrate-driven activation of NLP7, a master regulator of nitrate response in plants, fine tunes biosynthesis of cytokinin in roots and its translocation to shoots where it enhances expression of CRFs. CRFs, through direct transcriptional regulation of PIN auxin transporters, promote the flow of auxin and thereby stimulate the development of shoot organs.
PMID: 35878040
Proc Natl Acad Sci U S A , IF:11.205 , 2022 Aug , V119 (31) : Pe2121058119 doi: 10.1073/pnas.2121058119
RALF1 peptide triggers biphasic root growth inhibition upstream of auxin biosynthesis.
Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture, College of Horticulture, China Agricultural University, 100193 Beijing, China.; Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria.; Department of Biotechnology, College of Science, Taif University, 21944 Taif, Saudi Arabia.; Laboratory of Growth Regulators, Faculty of Science, Palacky University and Institute of Experimental Botany of the Czech Academy of Sciences, 78371 Olomouc, Czech Republic.
Plant cell growth responds rapidly to various stimuli, adapting architecture to environmental changes. Two major endogenous signals regulating growth are the phytohormone auxin and the secreted peptides rapid alkalinization factors (RALFs). Both trigger very rapid cellular responses and also exert long-term effects [Du et al., Annu. Rev. Plant Biol. 71, 379-402 (2020); Blackburn et al., Plant Physiol. 182, 1657-1666 (2020)]. However, the way, in which these distinct signaling pathways converge to regulate growth, remains unknown. Here, using vertical confocal microscopy combined with a microfluidic chip, we addressed the mechanism of RALF action on growth. We observed correlation between RALF1-induced rapid Arabidopsis thaliana root growth inhibition and apoplast alkalinization during the initial phase of the response, and revealed that RALF1 reversibly inhibits primary root growth through apoplast alkalinization faster than within 1 min. This rapid apoplast alkalinization was the result of RALF1-induced net H(+) influx and was mediated by the receptor FERONIA (FER). Furthermore, we investigated the cross-talk between RALF1 and the auxin signaling pathways during root growth regulation. The results showed that RALF-FER signaling triggered auxin signaling with a delay of approximately 1 h by up-regulating auxin biosynthesis, thus contributing to sustained RALF1-induced growth inhibition. This biphasic RALF1 action on growth allows plants to respond rapidly to environmental stimuli and also reprogram growth and development in the long term.
PMID: 35878023
Curr Biol , IF:10.834 , 2022 Sep , V32 (17) : P3838-3846.e5 doi: 10.1016/j.cub.2022.06.064
Apical dominance control by TAR-YUC-mediated auxin biosynthesis is a deep homology of land plants.
Department of Plant Biology, Swedish University of Agricultural Sciences, The Linnean Centre for Plant Biology in Uppsala, 750 07 Uppsala, Sweden.; Laboratoire Reproduction et Developpement des Plantes, Universite de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, INRIA, Lyon 69007, France; Experimental Biology Research Group, Institute of Biology, Faculty of Sciences, University of Neuchatel, 2000 Neuchatel, Switzerland.; Laboratoire Reproduction et Developpement des Plantes, Universite de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, INRIA, Lyon 69007, France; Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Universite Paris-Saclay, 78000 Versailles, France.; Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK.; Universite Paris-Saclay, CNRS, INRAE, Univ Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91405 Orsay, France; Universite de Paris, CNRS, INRAE, Institute of Plant Sciences Paris-Saclay (IPS2), 91405 Orsay, France.; Laboratoire Reproduction et Developpement des Plantes, Universite de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, INRIA, Lyon 69007, France. Electronic address: yoan.coudert@cnrs.fr.
A key aim in biology is to identify which genetic changes contributed to the evolution of form through time. Apical dominance, the inhibitory effect exerted by shoot apices on the initiation or outgrowth of distant lateral buds, is a major regulatory mechanism of plant form.(1) Nearly a century of studies in the sporophyte of flowering plants have established the phytohormone auxin as a front-runner in the search for key factors controlling apical dominance,(2)(,)(3) identifying critical roles for long-range polar auxin transport and local auxin biosynthesis in modulating shoot branching.(4-10) A capacity for lateral branching evolved by convergence in the gametophytic shoot of mosses and primed its diversification;(11) however, polar auxin transport is relatively unimportant in this developmental process,(12) the contribution of auxin biosynthesis genes has not been assessed, and more generally, the extent of conservation in apical dominance regulation within the land plants remains largely unknown. To fill this knowledge gap, we sought to identify genetic determinants of apical dominance in the moss Physcomitrium patens. Here, we show that leafy shoot apex decapitation releases apical dominance through massive and rapid transcriptional reprogramming of auxin-responsive genes and altering auxin biosynthesis gene activity. We pinpoint a subset of P. patens TRYPTOPHAN AMINO-TRANSFERASE (TAR) and YUCCA FLAVIN MONOOXYGENASE-LIKE (YUC) auxin biosynthesis genes expressed in the main and lateral shoot apices and show that they are essential for coordinating branch initiation and outgrowth. Our results demonstrate that local auxin biosynthesis acts as a pivotal regulator of apical dominance in moss and constitutes a shared mechanism underpinning shoot architecture control in land plants.
PMID: 35841890
J Hazard Mater , IF:10.588 , 2022 Aug , V441 : P129843 doi: 10.1016/j.jhazmat.2022.129843
Changes in the m6A RNA methylome accompany the promotion of soybean root growth by rhizobia under cadmium stress.
College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, People's Republic of China.; Daqing Branch, Heilongjiang Academy of Agricultural Sciences, Daqing 163316, Heilongjiang, People's Republic of China.; College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, People's Republic of China. Electronic address: qshchen@126.com.; College of Agriculture, Northeast Agricultural University, Harbin 150030, Heilongjiang, People's Republic of China. Electronic address: qizhaoming1860@126.com.
Cadmium (Cd) is the most widely distributed heavy metal pollutant in soil and has significant negative effects on crop yields and human health. Rhizobia can enhance soybean growth in the presence of heavy metals, and the legume-rhizobia symbiosis has been used to promote heavy-metal phytoremediation, but much remains to be learned about the molecular networks that underlie these effects. Here, we demonstrated that soybean root growth was strongly suppressed after seven days of Cd exposure but that the presence of rhizobia largely eliminated this effect, even prior to nodule development. Moreover, rhizobia did not appear to promote root growth by limiting plant Cd uptake: seedlings with and without rhizobia had similar root Cd concentrations. Previous studies have demonstrated a role for m6A RNA methylation in the response of rice and barley to Cd stress. We therefore performed transcriptome-wide m6A methylation profiling to investigate changes in the soybean RNA methylome in response to Cd with and without rhizobia. Here, we provide some of the first data on transcriptome-wide m6a RNA methylation patterns in soybean; m6A modifications were concentrated at the 3' UTR of transcripts and showed a positive relationship with transcript abundance. Transcriptome-wide m6A RNA methylation peaks increased in the presence of Cd, and the integration of m6A methylome and transcriptome results enabled us to identify 154 genes whose transcripts were both differentially methylated and differentially expressed in response to Cd stress. Annotation results suggested that these genes were associated with Ca(2+) homeostasis, ROS pathways, polyamine metabolism, MAPK signaling, hormones, and biotic stress responses. There were 176 differentially methylated and expressed transcripts under Cd stress in the presence of rhizobia. In contrast to the Cd-only gene set, they were also enriched in genes related to auxin, jasmonic acid, and brassinosteroids, as well as abiotic stress tolerance. They contained fewer genes related to Ca(2+) homeostasis and also included candidates with known functions in the legume-rhizobia symbiosis. These findings offer new insights into how rhizobia promote soybean root growth under Cd stress; they provide candidate genes for research on plant heavy metal responses and for the use of legumes in phytoremediation.
PMID: 36113351
J Hazard Mater , IF:10.588 , 2022 Aug , V435 : P129020 doi: 10.1016/j.jhazmat.2022.129020
Thiourea mediated ROS-metabolites reprogramming restores root system architecture under arsenic stress in rice.
Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400085, India; School of Biological sciencesUM-DAE Center for Excellence in Basic Sciences, University of Mumbai, Vidyanagari 400098, Mumbai.; Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400085, India; Division of crop production, ICAR- Indian Institute of Soybean Research, Khandwa Road, Indore 452001, (M.P), India.; Department of Botany, Savitribai Phule Pune University, Pune 411007, India.; Centre for Cellular and Molecular Platforms, GKVK Post, Bengaluru 560065, India.; Biophysics & Structural Genomics Division, Saha Institute of Nuclear Physics, Kolkata, India; Homi Bhabha National Institute, Mumbai 400094, India.; Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400085, India; Homi Bhabha National Institute, Mumbai 400094, India. Electronic address: ashish@barc.gov.in.
Arsenic (As) is a ubiquitous carcinogenic metalloid that enters into human food chain, through rice consumption. To unravel the conundrum of oxidative vs. reductive stress, the differential root-system architecture (RSA) was studied under As (a ROS producer) and thiourea (TU; a ROS scavenger) alone treatments, which indicated 0.80- and 0.74-fold reduction in the number of lateral roots (NLR), respectively compared with those of control. In case of As+TU treatment, NLR was increased by 4.35-fold compared with those of As-stress, which coincided with partial restoration of redox-status and auxin transport towards the root-tip. The expression levels of 16 ROS related genes, including RBOHC, UPB-1 C, SHR1, PUCHI, were quantified which provided the molecular fingerprint, in accordance with endogenous ROS signature. LC-MS based untargeted and targeted metabolomics data revealed that As-induced oxidative stress was metabolically more challenging than TU alone-induced reductive stress. Cis/trans-ferruloyl putrescine and gamma-glutamyl leucine were identified as novel As-responsive metabolites whose levels were decreased and increased, respectively under As+TU than As-treated roots. In addition, the overall amino acid accumulation was increased in As+TU than As-treated roots, indicating the improved nutritional availability. Thus, the study revealed dynamic interplay between "ROS-metabolites-RSA", to the broader context of TU-mediated amelioration of As-stress in rice.
PMID: 35650738
New Phytol , IF:10.151 , 2022 Sep doi: 10.1111/nph.18487
Systemic control of plant regeneration and wound repair.
The Institute of Plant Sciences, Faculty of Agriculture, The Hebrew University, Rehovot, 761000, Israel.
Plants have a broad capacity to regenerate damaged organs. The study of wounding in multiple developmental systems has uncovered many of the molecular properties underlying plants' competence for regeneration at the local cellular level. However, in nature, wounding is rarely localized to one place, and plants need to coordinate regeneration responses at multiple tissues with environmental conditions and their physiological state. Here, we review the evidence for systemic signals that regulate regeneration on a plant-wide level. We focus on the role of auxin and sugars as short and long-range signals in natural wounding contexts and discuss the varied origin of these signals in different regeneration scenarios. Together, this evidence calls for a broader, system-wide view of plant regeneration competence.
PMID: 36101501
New Phytol , IF:10.151 , 2022 Sep doi: 10.1111/nph.18483
Nodule INception (NIN)-independent epidermal events lead to bacterial entry during nodule development in peanut (Arachis hypogaea).
National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi, 110067, India.; Amity University Haryana, Amity Education Valley, Manesar, Panchgaon, Haryana, 122412, India.
Legumes can host nitrogen-fixing rhizobia inside root nodules. In model legumes, rhizobia enter via infection threads (ITs) and develop nodules where infection-zone contains a mixture of infected and uninfected cells. Peanut (Arachis hypogaea) diversified from model legumes ~50-55 million years ago. Rhizobia enter through 'cracks' to form nodules in peanut roots where the cells of infection-zone are uniformly infected. Phylogenomic studies indicated symbiosis as a labile trait in peanut. These atypical features prompted us to investigate the molecular mechanism of peanut nodule development. Combining cell biology, genetics, and genomic tools, we visualized the status of hormonal signaling in peanut nodule primordia. Moreover, we dissected the signaling modules of Nodule INception (NIN), a master regulator of both epidermal infection and cortical organogenesis. Cytokinin signaling operates in a broad zone, from the epidermis to the pericycle inside nodule primordia, while auxin signaling is narrower and focused. NIN is involved in the nodule organogenesis, but not in the crack entry. Nodulation Pectate Lyase (NPL), which remodels cell walls during IT-formation, is not required. Whereas Nodule enhanced Glycosyl Hydrolases (AhNGHs) is recruited for cell wall modification during crack entry. While the hormonal regulation is conserved, the function of the NIN signaling modules is diversified in peanut.
PMID: 36098671
New Phytol , IF:10.151 , 2022 Sep doi: 10.1111/nph.18474
Gravity sensing and responses in the coordination of the shoot gravitropic setpoint angle.
Division of Plant Environmental Responses, National Institute for Basic Biology, Myodaiji, Okazaki, 444-8556, Japan.
Gravity is one of the fundamental environmental cues that affect plant development. Indeed, the plant architecture in the shoots and roots is modulated by gravity. Stems grow vertically upward, whereas lateral organs, such as the lateral branches in shoots, tend to grow at a specific angle according to a gravity vector known as the gravitropic setpoint angle. During this process, gravity is sensed in specialized gravity-sensing cells named statocytes, which convert gravity information into biochemical signals, leading to asymmetric auxin distribution and driving asymmetric cell division/expansion in the organs to achieve gravitropism. As a hypothetical offset mechanism against gravitropism to determine the gravitropic setpoint angle, the anti-gravitropic offset has been proposed. According to this concept, the gravitropic setpoint angle is a balance of two antagonistic growth components, i.e., gravitropism and the anti-gravitropic offset. Although the nature of the anti-gravitropic offset has not been clarified, studies have suggested that gravitropism and the anti-gravitropic offset share a common gravity-sensing mechanism in statocytes. This review discusses the molecular mechanisms underlying gravitropism as well as the hypothetical anti-gravitropic offset in the control of the gravitropic setpoint angle.
PMID: 36089891
New Phytol , IF:10.151 , 2022 Sep doi: 10.1111/nph.18467
Phosphorylation status of Bbeta subunit acts as a switch to regulate the function of phosphatase PP2A in ethylene-mediated root growth inhibition.
Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, 78712, USA.; Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, 78712, USA.; Haixia Institute of Science and Technology, Horticultural Plant Biology and Metabolomics Center, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.
The various combinations and regulations of different subunits of phosphatase PP2A holoenzymes underlie their functional complexity and importance. However, molecular mechanisms governing the assembly of PP2A complex in response to external or internal signals remain largely unknown, especially in Arabidopsis thaliana. We found that the phosphorylation status of Bbeta of PP2A acts as a switch to regulate the activity of PP2A. In the absence of ethylene, phosphorylated Bbeta leads to an inactivation of PP2A; the substrate EIR1 remains to be phosphorylated, preventing the EIR1-mediated auxin transport in epidermis, leading to normal root growth. Upon ethylene treatment, the dephosphorylated Bbeta mediates the formation of the A2-C4-Bbeta protein complex to activate PP2A, resulting in the dephosphorylation of EIR1 to promote auxin transport in epidermis of elongation zone, leading to root growth inhibition. Altogether, our research revealed a novel molecular mechanism by which the dephosphorylation of Bbeta subunit switches on PP2A activity to dephosphorylate EIR1 to establish EIR1-mediated auxin transport in the epidermis in elongation zone for root growth inhibition in response to ethylene.
PMID: 36073540
New Phytol , IF:10.151 , 2022 Sep doi: 10.1111/nph.18459
Karrikin signaling regulates hypocotyl shade avoidance response by modulating auxin homeostasis in Arabidopsis.
Laboratory of Photosynthesis and Environment, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, 200032, China.; University of Chinese Academy of Sciences, Beijing, 100039, China.
Shade affects all aspects of plant growth and development, including seed germination, hypocotyl elongation, petiole growth, leaf hyponasty, and flowering time. Here, we found that mutations in the key Arabidopsis karrikins signal perception-associated KARRIKIN INSENSITIVE 2 (KAI2) gene, encoding an alpha/beta-fold hydrolase, and the MORE AXILLARY GROWTH 2 (MAX2) gene, encoding an F-box protein, led to greater hypocotyl elongation under shade avoidance conditions. We further verified that these phenotypes were caused by perception of the endogenous KAI2-ligands (KLs), and that this phenotype is independent of strigolactone biosynthetic or signaling pathways. Upon perception of a KL, it is probable that the target protein forms a complex with the KAI2/MAX2 proteins, which are degraded through the action of the 26S proteasome. We demonstrated that SUPPRESSOR OF MAX2-1 (SMAX1) is the degradation target for the KAI2/MAX2 complex in the context of shade avoidance. KAI2 and MAX2 require SMAX1 to limit the hypocotyl growth associated with shade avoidance. Treatment with l-kynurenine, an inhibitor of auxin accumulation, partially restored elongation of kai2 mutant hypocotyls under simulated shade. Furthermore, KAI2 is involved in regulating auxin accumulation and polar auxin transport, which may contribute to the hypocotyl shade response. In addition, SMAX1 gene overexpression promoted the hypocotyl shade response. RNA-sequencing analysis revealed that SMAX1-overexpression affected the expression of many auxin homeostasis genes, especially under simulated shade. Altogether, our data support the conclusion that KL signaling regulates shade avoidance by modulating auxin homeostasis in the hypocotyl.
PMID: 36068957
New Phytol , IF:10.151 , 2022 Aug doi: 10.1111/nph.18448
Bipartite phosphoinositide-dependent modulation of auxin signaling during xylem differentiation in Arabidopsis thaliana roots.
Department of Biology, Swiss Federal Institute of Technology (ETH) Zurich, CH-8092, Zurich, Switzerland.
Efficient root-to-shoot delivery of water and nutrients in plants relies on the correct differentiation of xylem cells into hollow elements. While auxin is integral to the formation of xylem cells, it remains poorly characterized how each subcellular pool of this hormone regulates this process. Combining genetic and cell biological approaches, we investigated the bipartite activity of nucleoplasmic vs plasma membrane-associated phosphatidylinositol 4-phosphate kinases PIP5K1 and its homolog PIP5K2 in Arabidopsis thaliana roots and uncovered a novel mechanism by which phosphoinositides integrate distinct aspects of the auxin signaling cascade and, in turn, regulate the onset of xylem differentiation. The appearance of undifferentiated cells in protoxylem strands of pip5k1 pip5k2 is phenomimicked in auxin transport and perception mutants and can be partially restored by the nuclear residence of PIP5K1. By contrast, exclusion of PIP5K1 from the nucleus hinders the auxin-mediated induction of the xylem master regulator VASCULAR RELATED NAC DOMAIN (VND) 7. A xylem-specific increase of auxin levels abolishes pip5k1 pip5k2 vascular defects, indicating that the establishment of auxin maxima is required to activate VND7-mediated xylem differentiation. Our results describe a new mechanism by which distinct subcellular pools of phosphoinositides integrate auxin transport and perception to initiate xylem differentiation in a spatiotemporal manner.
PMID: 36039703
New Phytol , IF:10.151 , 2022 Aug doi: 10.1111/nph.18440
Feedback regulation of auxin signaling through the transcription of H2A.Z and deposition of H2A.Z to SMALL AUXIN UP RNAs in Arabidopsis.
Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China.; National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 200032, China.
Auxin is a critical phytohormone that is involved in the regulation of most plant growth and developmental responses. In particular, epigenetic mechanisms, like histone modifications and DNA methylation, were reported to affect auxin biosynthesis and transport. However, the involvement of other epigenetic factors, such as histone variant H2A.Z, in the auxin-related developmental regulation remains unclear. We report that the histone variant H2A.Z knockdown mutant in Arabidopsis Col-0 ecotype, h2a.z-kd, has more lateral roots and weak gravitational responses related to auxin-regulated growth performances. Further study revealed that auxin promotes the eviction of H2A.Z from the auxin-responsive genes SMALL AUXIN-UP RNAs (SAURs) to activate their transcriptions. We found that IAA promotes the transcription of H2A.Z genes through HOMEOBOX PROTEIN 22/25 (AtHB22/25) transcription factors which work as downstream targets of ARF7/19 in auxin signaling. Double mutant of hb22 hb25 showed similar lateral root and gravitropism phenotypes to h2a.z-kd. Our results shed light on a reciprocal regulation hub through INOSITOL AUXOTROPHY 80-mediated H2A.Z eviction and ARF7/19-HB22/25-mediated H2A.Z transcription to modulate the activation of SAURs and plant growth in Arabidopsis.
PMID: 36017638
New Phytol , IF:10.151 , 2022 Aug doi: 10.1111/nph.18315
Many ways to TOPLESS - manipulation of plant auxin signalling by a cluster of fungal effectors.
Gregor Mendel Institute (GMI), Austrian Academy of Sciences (OEAW), Vienna Bio Center (VBC), Dr. Bohr-Gasse 3, 1030, Vienna, Austria.; Department of Plant Pathology, Institute of Crop Science and Resource Conservation (INRES), University of Bonn, Nussallee 9, 53115, Bonn, Germany.; CEPLAS, Institute for Plant Sciences, University of Cologne, 50674, Cologne, Germany.; Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), OT Gatersleben, Corrensstrasse 3, D-06466, Stadt Seeland, Germany.
Plant biotrophic pathogens employ secreted molecules, called effectors, to suppress the host immune system and redirect the host's metabolism and development in their favour. Putative effectors of the gall-inducing maize pathogenic fungus Ustilago maydis were analysed for their ability to induce auxin signalling in plants. Using genetic, biochemical, cell-biological, and bioinformatic approaches we functionally elucidate a set of five, genetically linked effectors, called Topless (TPL) interacting protein (Tips) effectors that induce auxin signalling. We show that Tips induce auxin signalling by interfering with central corepressors of the TPL family. CRISPR-Cas9 mutants and deletion strain analysis indicate that the auxin signalling inducing subcluster effectors plays a redundant role in virulence. Although none of the Tips seem to have a conserved interaction motif, four of them bind solely to the N-terminal TPL domain and, for Tip1 and Tip4, we demonstrate direct competition with auxin/indole-3-acetic acid transcriptional repressors for their binding to TPL class of corepressors. Our findings reveal that TPL proteins, key regulators of growth-defence antagonism, are a major target of the U. maydis effectome.
PMID: 35944559
New Phytol , IF:10.151 , 2022 Sep , V235 (6) : P2270-2284 doi: 10.1111/nph.18317
miR169o and ZmNF-YA13 act in concert to coordinate the expression of ZmYUC1 that determines seed size and weight in maize kernels.
Biotechnology Research Institute, CAAS/Key Laboratory of Agricultural Genomics (Beijing), Ministry of Agriculture, 100081, Beijing, China.; National Nanfan Research Institute (Sanya), 572022, Sanya, Hainan, China.; National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101, Beijing, China.; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, 100039, Beijing, China.
MicroRNAs (miRNAs) play key regulatory roles in seed development and emerge as new key targets for engineering grain size and yield. The Zma-miRNA169 family is highly expressed during maize seed development, but its functional roles in seed development remain elusive. Here, we generated zma-miR169o and ZmNF-YA13 transgenic plants. Phenotypic and genetic analyses were performed on these lines. Seed development and auxins contents were investigated. Overexpression of maize miRNA zma-miR169o increases seed size and weight, whereas the opposite is true when its expression is suppressed. Further studies revealed that zma-miR169 acts by negatively regulating its target gene, a transcription factor ZmNF-YA13 that also plays a key role in determining seed size. We demonstrate that ZmNF-YA13 regulates the expression of the auxin biosynthetic gene ZmYUC1, which modulates auxin levels in the early developing seeds and determines the number of endosperm cells, thereby governing maize seed size and ultimately yield. Overall, our present study has identified zma-miR169o and ZmNF-YA13 that form a functional module regulating auxin accumulation in maize seeds and playing an important role in determining maize seed size and yield, providing a set of novel molecular tools for yield improvement in molecular breeding and genetic engineering.
PMID: 35713356
Plant Biotechnol J , IF:9.803 , 2022 Sep doi: 10.1111/pbi.13930
A HST1-like gene controlled tiller angle through regulating endogenous auxin in common wheat.
National Key Laboratory of Wheat and Maize Crop Science / CIMMYT-China Wheat and Maize Joint Research Center /Agronomy College, Henan Agricultural University, Zhengzhou, China.
Tiller angle is one of the most important agronomic traits and one key factor for wheat ideal plant architecture, which can both increase photosynthetic efficiency and greatly enhance grain yield. Here, a deacetylase HST1-like (TaHST1L) gene controlling wheat tiller angle was identified by the combination of a genome-wide association study (GWAS) and bulked segregant analysis (BSA). Ethyl methane sulfonate (EMS)-mutagenized tetraploid wheat lines with the premature stop codon of TaHST1L exhibited significantly smaller tiller angles than the wild type. TaHST1L-overexpressing (OE) plants exhibited significantly larger tiller angles and increased tiller numbers in both winter and spring wheat, while TaHST1L-silenced RNAi plants displayed significantly smaller tiller angles and decreased tiller numbers. Moreover, TaHST1L strongly interacted with TaIAA17 and inhibited its expression at the protein level, and thus possibly improved the content of endogenous auxin in the basal tissue of tillers. The transcriptomics and metabolomics results indicated that TaHST1L might change plant architecture by mediating auxin signal transduction and regulating endogenous auxin levels. In addition, a 242-bp insertion/deletion (InDel) in the TaHST1L-A1 promoter altered transcriptional activity and TaHST1L-A1b allele with the 242-bp insertion widened the tiller angle of TaHST1L-OE transgenic rice plants. Wheat varieties with TaHST1L-A1b allele possessed the increased tiller angle and grain yield. Further analysis in wheat and its progenitors indicated that the 242-bp InDel possibly originated from wild emmer and was strongly domesticated in the current varieties. Therefore, TaHST1L involved in the auxin signaling pathway showed the big potential to improve wheat yield by controlling plant architecture.
PMID: 36128872
Plant Biotechnol J , IF:9.803 , 2022 Sep , V20 (9) : P1756-1769 doi: 10.1111/pbi.13861
The upregulated LsKN1 gene transforms pinnately to palmately lobed leaves through auxin, gibberellin, and leaf dorsiventrality pathways in lettuce.
Key Laboratory of Horticultural Plant Biology, Ministry of Education, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, China.; Genome Center and Department of Plant Sciences, University of California, Davis, California, USA.
Leaf shape represents a vital agronomic trait for leafy vegetables such as lettuce. Some lettuce cultivars produce lobed leaves, varying from pinnately to palmately lobed, but the genetic mechanisms remain unclear. In this study, we cloned one major quantitative trait locus (QTL) controlling palmately lobed leaves. The candidate gene, LsKN1, encodes a homeobox transcription factor, and has been shown previously to be critical for the development of leafy heads in lettuce. The LsKN1 allele that is upregulated by the insertion of a transposon promotes the development of palmately lobed leaves. We demonstrated that LsKN1 upregulated LsCUC2 and LsCUC3 through different mechanisms, and their upregulation was critical for the development of palmately lobed leaves. LsKN1 binds the promoter of LsPID to promote auxin biosynthesis, which positively contributes to the development of palmately lobed leaves. In contrast, LsKN1 suppresses GA biosynthesis to promote palmately lobed leaves. LsKN1 also binds to the promoter of LsAS1, a dorsiventrality gene, to downregulate its expression. Overexpression of the LsAS1 gene compromised the effects of the LsKN1 gene changing palmately to pinnately lobed leaves. Our study illustrated that the upregulated LsKN1 gene led to palmately lobed leaves in lettuce by integrating several downstream pathways, including auxin, gibberellin, and leaf dorsiventrality pathways.
PMID: 35634731
Plant Physiol , IF:8.34 , 2022 Sep doi: 10.1093/plphys/kiac447
Abscisic Acid Modulates Neighbor Proximity-Induced Leaf Hyponasty in Arabidopsis.
Faculty of Biology and Medicine, Centre for Integrative Genomics, University of Lausanne, Genopode Building, Lausanne CH-1015, Switzerland.; Plant Biochemistry, Department of Biology, ETH Zurich, Universitat-Str. 2, CH-8092 Zurich, Switzerland.; Department of Plant Sciences, Downing Street, Cambridge, University of Cambridge, CB2 3EA, United Kingdom.
Leaves of shade-avoiding plants such as Arabidopsis (Arabidopsis thaliana) change their growth pattern and position in response to low red to far-red ratios (LRFRs) encountered in dense plant communities. Under LRFR, transcription factors of the phytochrome interacting factor (PIF) family are de-repressed. PIFs induce auxin production, which is required for promoting leaf hyponasty, thereby favoring access to unfiltered sunlight. Abscisic acid (ABA) has also been implicated in the control of leaf hyponasty, with gene expression patterns suggesting that LRFR regulates the ABA response. Here, we show that LRFR leads to a rapid increase in ABA levels in leaves. Changes in ABA levels depend on PIFs, which regulate the expression of genes encoding isoforms of the enzyme catalyzing a rate-limiting step in ABA biosynthesis. Interestingly, ABA biosynthesis and signaling mutants have more erect leaves than wild-type Arabidopsis under white light but respond less to LRFR. Consistent with this, ABA application decreases leaf angle under white light; however, this response is inhibited under LRFR. Tissue-specific interference with ABA signaling indicates that an ABA response is required in different cell types for LRFR-induced hyponasty. Collectively, our data indicate that LRFR triggers rapid PIF-mediated ABA production. ABA plays a different role in controlling hyponasty under white light than under LRFR. Moreover, ABA exerts its activity in multiple cell types to control leaf position.
PMID: 36135791
Plant Physiol , IF:8.34 , 2022 Sep doi: 10.1093/plphys/kiac440
Abscisic acid-responsive transcription factors PavDof2/6/15 mediate fruit softening in sweet cherry.
Department of Pomology, College of Horticulture, China Agricultural University, Beijing 100193, China.
Softening is a key step during fruit ripening that is modulated by the interplay between multiple phytohormones. The antagonistic action of abscisic acid (ABA) and auxin determines the rate of fruit ripening and softening. However, the transcription factors that integrate ABA and auxin signals to regulate fruit softening remain to be determined. In this study, we identified several DNA-binding with One Finger (Dof) transcription factors essential for ABA-promoted fruit softening, based on transcriptome analysis of two sweet cherry (Prunus avium L.) varieties with different fruit firmness. We show that PavDof6 directly binds to the promoters of genes encoding cell wall-modifying enzymes to activate their transcription, while PavDof2/15 directly repress their transcription. Transient overexpression of PavDof6 and PavDof2/15 in sweet cherry fruits resulted in precocious and delayed softening, respectively. In addition, we show that the auxin response factor PavARF8, the expression of whose encoding gene is repressed by ABA, activates PavDof2/15 transcription. Furthermore, PavDof2/6/15 and PavARF8 directly bind to the 9-cis-epoxycarotenoid dioxygenase 1 (PavNCED1) promoter and regulate its expression, forming a feedback mechanism for ABA-mediated fruit softening. These findings unveil the physiological framework of fruit softening and establish a direct functional link between the ABA-PavARF8-PavDofs module and cell wall-modifying genes in mediating fruit softening.
PMID: 36130298
Plant Physiol , IF:8.34 , 2022 Sep doi: 10.1093/plphys/kiac441
Ethylene response factor ERF.D7 activates Auxin response factor 2 paralogs to regulate tomato fruit ripening.
Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi 110021, India.; Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India.
Despite the obligatory role of ethylene in climacteric fruit ripening and the identification of 77 ethylene response factors (ERFs) in the tomato (Solanum lycopersicum) genome, the role of few ERFs has been validated in the ripening process. Here, using a comprehensive morpho-physiological, molecular and biochemical approach, we demonstrate the regulatory role of Ethylene Response Factor D7 (SlERF.D7) in tomato fruit ripening. SlERF.D7 expression positively responded to exogenous ethylene and auxin treatments, most likely in a Ripening Inhibitor (RIN)-independent manner. SlERF.D7 overexpression promoted ripening, and its silencing had the opposite effect. Alterations in its expression modulated ethylene production, pigment accumulation, and fruit firmness. Consistently, genes involved in ethylene biosynthesis and signalling, lycopene biosynthesis, and cell wall loosening were upregulated in the overexpression lines and downregulated in RNAi lines. These transgenic lines also accumulated altered levels of IAA at late-breaker stages. A positive association between Auxin Response Factor 2 (ARF2) paralog's transcripts and SlERF.D7 mRNA levels and that SlARF2A and SlARF2B are direct targets of SlERF.D7 underpinned the perturbed auxin-ethylene crosstalk for the altered ripening program observed in the transgenic fruits. Overall, this study uncovers that SlERF.D7 positively regulates SlARF2A/B abundance to amalgamate auxin and ethylene signalling pathways for controlling tomato fruit ripening.
PMID: 36130295
Plant Physiol , IF:8.34 , 2022 Sep doi: 10.1093/plphys/kiac425
INOSITOL (1,3,4) TRIPHOSPHATE 5/6 KINASE1-Dependent Inositol Polyphosphates Regulate Auxin Responses in Arabidopsis.
Department of Plant Nutrition, Institute of Crop Science and Resource Conservation, Rheinische Friedrich-Wilhelms-Universitat Bonn, 53115 Bonn, Germany.; Department of Physiology & Cell Biology, Leibniz-Institute of Plant Genetics and Crop Plant Research, 06466 Gatersleben, Germany.; Department of Chemistry and Pharmacy & CIBSS - the Center for Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany.; Department of Biochemistry, Indian Institute of Science, Bengaluru 560012, India.; Laboratory of Signal Transduction and Plant Resistance, Regional Centre for Biotechnology, NCR-Biotech Science Cluster, Faridabad - 121001. Haryana, India.; Department of Pharmacology, Howard Hughes Medical Institute, University of Washington, Seattle, Washington 98195, USA.; Medical Research Council Laboratory for Molecular Cell Biology (MRC-LMCB), University College London, London WC1E 6BT, United Kingdom.
The combinatorial phosphorylation of myo-inositol results in the generation of different inositol phosphates (InsPs), of which phytic acid (InsP6) is the most abundant species in eukaryotes. InsP6 is also an important precursor of the higher phosphorylated inositol pyrophosphates (PP-InsPs), such as InsP7 and InsP8, which are characterized by a diphosphate moiety and are also ubiquitously found in eukaryotic cells. While PP-InsPs regulate various cellular processes in animals and yeast, their biosynthesis and functions in plants has remained largely elusive because plant genomes do not encode canonical InsP6 kinases. Recent work has shown that Arabidopsis (Arabidopsis thaliana) INOSITOL (1,3,4) TRIPHOSPHATE 5/6 KINASE1 (ITPK1) and ITPK2 display in vitro InsP6 kinase activity and that, in planta, ITPK1 stimulates 5-InsP7 and InsP8 synthesis and regulates phosphate starvation responses. Here we report a critical role of ITPK1 in auxin-related processes that is independent of the ITPK1-controlled regulation of phosphate starvation responses. Those processes include primary root elongation, root hair development, leaf venation, thermomorphogenic and gravitropic responses, and sensitivity to exogenously applied auxin. We found that the recombinant auxin receptor complex, consisting of the F-Box protein TRANSPORT INHIBITOR RESPONSE1 (TIR1), ARABIDOPSIS SKP1 HOMOLOGUE 1 (ASK1) and the transcriptional repressor INDOLE-3-ACETIC ACID INDUCIBLE 7 (IAA7), binds to anionic inositol polyphosphates with high affinity. We further identified a physical interaction between ITPK1 and TIR1, suggesting a localized production of 5-InsP7, or another ITPK1-dependent InsP/PP-InsP isomer, to activate the auxin receptor complex. Finally, we demonstrate that ITPK1 and ITPK2 function redundantly to control auxin responses, as deduced from the auxin-insensitive phenotypes of itpk1 itpk2 double mutant plants. Our findings expand the mechanistic understanding of auxin perception and suggest that distinct inositol polyphosphates generated near auxin receptors help to fine-tune auxin sensitivity in plants.
PMID: 36124979
Plant Physiol , IF:8.34 , 2022 Sep doi: 10.1093/plphys/kiac418
Root acid phosphatases and rhizobacteria synergistically enhance white lupin and rice phosphorus acquisition.
Joint International Research Laboratory of Water and Nutrient in Crops, Haixia Institute of Ecology and Environmental Engineering, College of Resource and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.; College of Agriculture, Yangzhou University, Yangzhou, 225009, China.; Department of Biology, Hong Kong Baptist University, Stake Key Laboratory of Agrobiotechnology and Chinese University of Hong Kong, Hong Kong.; Institute of Agricultural Sciences, ICA-CSIC, Madrid, Spain.; The UWA Institute of Agriculture and School of Agriculture and Environment, University of Western Australia, Perth, WA 6009, Australia.; College of Horticulture, South China Agricultural University, Guangzhou, China.
The rhizosheath is a belowground area that acts as a communication hub at the root-soil interface to promote water and nutrient acquisition. Certain crops, such as white lupin (Lupinus albus), acquire large amounts of phosphorus (P), owing partially to exudation of acid phosphatases (APases). Plant growth-promoting rhizobacteria also increase soil P availability. However, potential synergistic effects of root APases and rhizosheath-associated microbiota on P acquisition require further research. In this study, we investigated the roles of root purple APases (PAPs) and plant growth-promoting rhizobacteria in rhizosheath formation and P acquisition under conditions of soil drying (SD) and P treatment (+P: soil with P fertilizer; -P: soil without fertilizer). We expressed purple acid phosphatase12 (LaPAP12) in white lupin and rice (Oryza sativa) plants and analyzed the rhizosheath-associated microbiome. Increased or heterologous LaPAP12 expression promoted APase activity and rhizosheath formation, resulting in increased P acquisition mainly under SD-P conditions. It also increased the abundance of members of the genus Bacillus in the rhizosheath-associated microbial communities of white lupin and rice. We isolated a phosphate-solubilizing, auxin-producing Bacillus megaterium strain from the rhizosheath of white lupin and used this to inoculate white lupin and rice plants. Inoculation promoted rhizosheath formation and P acquisition, especially in plants with increased LaPAP12 expression and under SD-P conditions, suggesting a functional role of the bacteria in alleviating P deficit stress via rhizosheath formation. Together, our results suggest a synergistic enhancing effect of LaPAP12 and plant growth-promoting rhizobacteria on rhizosheath formation and P acquisition under SD-P conditions.
PMID: 36066452
Plant Physiol , IF:8.34 , 2022 Sep doi: 10.1093/plphys/kiac412
PHYTOCHROME-INTERACTING FACTOR 4/HEMERA-mediated thermosensory growth requires the Mediator subunit MED14.
Department of Biology, University of Mississippi, Oxford, MS 38677, USA.; Natural Products Utilization Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Oxford, Mississippi, USA.; National Center for Natural Products Research, School of Pharmacy, University of Mississippi, Oxford, Mississippi, USA.; Division of Pharmacology, Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, Oxford, Mississippi, USA.
While moderately elevated ambient temperatures do not trigger stress responses in plants, they do substantially stimulate the growth of specific organs through a process known as thermomorphogenesis. The basic helix-loop-helix transcription factor PHYTOCHROME-INTERACTING FACTOR 4 (PIF4) plays a central role in regulating thermomorphogenetic hypocotyl elongation in various plant species, including Arabidopsis (Arabidopsis thaliana). Although it is well known that PIF4 and its co-activator HEMERA (HMR) promote plant thermosensory growth by activating genes involved in the biosynthesis and signaling of the phytohormone auxin, the detailed molecular mechanism of such transcriptional activation is not clear. In this report, we investigated the role of the Mediator complex in the PIF4/HMR-mediated thermoresponsive gene expression. Through the characterization of various mutants of the Mediator complex, a tail subunit named MED14 was identified as an essential factor for thermomorphogenetic hypocotyl growth. MED14 was required for the thermal induction of PIF4 target genes but had a marginal effect on the levels of PIF4 and HMR. Further transcriptomic analyses confirmed that the expression of numerous PIF4/HMR-dependent, auxin-related genes required MED14 at warm temperatures. Moreover, PIF4 and HMR physically interacted with MED14 and both were indispensable for the association of MED14 with the promoters of these thermoresponsive genes. While PIF4 did not regulate MED14 levels, HMR was required for the transcript abundance of MED14. Taken together, these results unveil an important thermomorphogenetic mechanism, in which PIF4 and HMR recruit the Mediator complex to activate auxin-related growth-promoting genes when plants sense moderate increases in ambient temperature.
PMID: 36063057
Plant Physiol , IF:8.34 , 2022 Sep doi: 10.1093/plphys/kiac407
Abscisic acid inhibits primary root growth by impairing ABI4-mediated cell cycle and auxin biosynthesis.
School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, 710129, China.; College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China.; Institute of Ecological Agriculture, Sichuan Agricultural University, Chengdu, 611130, China.
Cell cycle progression and the phytohormones auxin and abscisic acid (ABA) play key roles in primary root growth, but how ABA mediates the transcription of cell cycle-related genes and the mechanism of crosstalk between ABA and auxin requires further research. Here, we report that ABA inhibits primary root growth by regulating the ABSCISIC ACID INSENSITIVE4 (ABI4)- CYCLIN-DEPENDENT KINASE B2;2 (CDKB2;2)/CYCLIN B1;1 (CYCB1;1) module-mediated cell cycle as well as auxin biosynthesis in Arabidopsis (Arabidopsis thaliana). ABA induced ABI4 transcription in the primary root tip, and the abi4 mutant showed an ABA-insensitive phenotype in primary root growth. Compared with the wild-type (WT), the meristem size and cell number of the primary root in abi4 increased in response to ABA. Further, the transcription levels of several cell-cycle positive regulator genes, including CDKB2;2 and CYCB1;1, were upregulated in abi4 primary root tips. Subsequent ChIP-seq, ChIP-qPCR and biochemical analysis revealed that ABI4 repressed the expression of CDKB2;2 and CYCB1;1 by physically interacting with their promoters. Genetic analysis demonstrated that overexpression of CDKB2;2 or CYCB1;1 fully rescued the shorter primary root phenotype of ABI4-overexpression lines, and consistently, abi4/cdkb2;2-cr or abi4/cycb1;1-cr double mutations largely rescued the ABA- insensitive phenotype of abi4 with regard to primary root growth. The expression levels of DR5promoter-GFP and PIN1promoter::PIN1-GFP in abi4 primary root tips were significantly higher than those in WT after ABA treatment, with these changes being consistent with changes in auxin concentration and expression patterns of auxin biosynthesis genes. Taken together, these findings indicated that ABA inhibits primary root growth through ABI4-mediated cell cycle and auxin-related regulatory pathways.
PMID: 36047837
Plant Physiol , IF:8.34 , 2022 Aug doi: 10.1093/plphys/kiac374
Identification of growth regulators using cross-species network analysis in plants.
Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, 9052 Ghent, Belgium.; VIB Center for Plant Systems Biology, Technologiepark 71, 9052 Ghent, Belgium.; Institute of Biosciences and Bioresources, National Research Council (CNR), Via Amendola 165/A, 70126 Bari, Italy.; Umea Plant Science Centre (UPSC), Department of Plant Physiology, Umea University, 90187 Umea, Sweden.; SweTree Technologies AB, Skogsmarksgrand 7, SE-907 36 Umea, Sweden.; Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, 1432 As, Norway.; Umea Plant Science Centre (UPSC), Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, 90183 Umea, Sweden.; Bioinformatics Institute Ghent, Ghent University, Technologiepark 71, 9052 Ghent, Belgium.
With the need to increase plant productivity, one of the challenges plant scientists are facing is to identify genes that play a role in beneficial plant traits. Moreover, even when such genes are found, it is generally not trivial to transfer this knowledge about gene function across species to identify functional orthologs. Here, we focused on the leaf to study plant growth. First, we built leaf growth transcriptional networks in Arabidopsis (Arabidopsis thaliana), maize (Zea mays), and aspen (Populus tremula). Next, known growth regulators, here defined as genes that when mutated or ectopically expressed alter plant growth, together with cross-species conserved networks, were used as guides to predict novel Arabidopsis growth regulators. Using an in-depth literature screening, 34 out of 100 top predicted growth regulators were confirmed to affect leaf phenotype when mutated or overexpressed and thus represent novel potential growth regulators. Globally, these growth regulators were involved in cell cycle, plant defense responses, gibberellin, auxin, and brassinosteroid signaling. Phenotypic characterization of loss-of-function lines confirmed two predicted growth regulators to be involved in leaf growth (NPF6.4 and LATE MERISTEM IDENTITY2). In conclusion, the presented network approach offers an integrative cross-species strategy to identify genes involved in plant growth and development.
PMID: 35984294
Plant Physiol , IF:8.34 , 2022 Aug doi: 10.1093/plphys/kiac370
Cell- and non-cell-autonomous AUXIN RESPONSE FACTOR3 controls meristem proliferation and phyllotactic patterns.
State Key Laboratory of North China Crop Improvement and Regulation, College of Agronomy, Hebei Agricultural University; Key Laboratory of Crop Growth Regulation of Hebei Province, Baoding, Hebei, 071001, China.; Ministry of Education Key Laboratory of Molecular and Cellular Biology, Hebei Key Laboratory of Molecular and Cellular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, China; Hebei Collaboration Innovation Center for Cell Signaling, Shijiazhuang, China.; State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, College of Life Sciences, Hebei Agricultural University, Baoding, China.; State Key Laboratory of Plant Cell and Chromosome Engineering, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Shijiazhuang, China.
In cell-cell communication, non-cell-autonomous transcription factors play vital roles in controlling plant stem cell fate. We previously reported that AUXIN RESPONSE FACTOR3 (ARF3), a member of the ARF family with critical roles in floral meristem maintenance and determinacy, has a distinct accumulation pattern that differs from the expression domain of its encoding gene in the shoot apical meristem (SAM). However, the biological meaning of this difference is obscure. Here, we demonstrate that ARF3 expression in Arabidopsis (Arabidopsis thaliana) is mainly activated at the periphery of the SAM by auxin where ARF3 cell-autonomously regulates the expression of meristem-organ boundary-specific genes, such as CUP-SHAPED COTYLEDON1-3 (CUC1-3), BLADE ON PETIOLE1-2 (BOP1-2) and TARGETS UNDER ETTIN CONTROL3 (TEC3) to regulate the arrangement of organs in regular pattern, a phenomenon referred to as phyllotaxis. We also show that ARF3 is translocated into the organizing center where it represses cytokinin activity and WUSCHEL expression to regulate meristem activity non-cell-autonomously. Therefore, ARF3 acts as a molecular link that mediates the interaction of auxin and cytokinin signaling in the SAM while coordinating the balance between meristem maintenance and organogenesis. Our findings reveal an ARF3-mediated coordination mechanism through cell-cell communication in dynamic SAM maintenance.
PMID: 35972411
Plant Physiol , IF:8.34 , 2022 Sep , V190 (2) : P1457-1473 doi: 10.1093/plphys/kiac332
Class I TCP transcription factor AtTCP8 modulates key brassinosteroid-responsive genes.
Department of Biological Sciences, Butler University, Indianapolis, Indiana, USA.; Division of Plant Science and Technology, University of Missouri, Columbia, Missouri, USA.; Christopher S. Bond Life Sciences Center and Interdisciplinary Plant Group, University of Missouri, Columbia, Missouri, USA.; Department of Biology, Marian University, Indianapolis, Indiana, USA.
The plant-specific TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR (TCP) transcription factor family is most closely associated with regulating plant developmental programs. Recently, TCPs were also shown to mediate host immune signaling, both as targets of pathogen virulence factors and as regulators of plant defense genes. However, comprehensive characterization of TCP gene targets is still lacking. Loss of function of the class I TCP gene AtTCP8 attenuates early immune signaling and, when combined with mutations in AtTCP14 and AtTCP15, additional layers of defense signaling in Arabidopsis (Arabidopsis thaliana). Here, we focus on TCP8, the most poorly characterized of the three to date. We used chromatin immunoprecipitation and RNA sequencing to identify TCP8-bound gene promoters and differentially regulated genes in the tcp8 mutant; these datasets were heavily enriched in signaling components for multiple phytohormone pathways, including brassinosteroids (BRs), auxin, and jasmonic acid. Using BR signaling as a representative example, we showed that TCP8 directly binds and activates the promoters of the key BR transcriptional regulatory genes BRASSINAZOLE-RESISTANT1 (BZR1) and BRASSINAZOLE-RESISTANT2 (BZR2/BES1). Furthermore, tcp8 mutant seedlings exhibited altered BR-responsive growth patterns and complementary reductions in BZR2 transcript levels, while TCP8 protein demonstrated BR-responsive changes in subnuclear localization and transcriptional activity. We conclude that one explanation for the substantial targeting of TCP8 alongside other TCP family members by pathogen effectors may lie in its role as a modulator of BR and other plant hormone signaling pathways.
PMID: 35866682
Plant Physiol , IF:8.34 , 2022 Aug , V190 (1) : P794-812 doi: 10.1093/plphys/kiac288
Initiation of aboveground organ primordia depends on combined action of auxin, ERECTA family genes, and PINOID.
Department of Biochemistry, Cellular and Molecular Biology, The University of Tennessee, Knoxville, Tennessee 37996, USA.; UT-ORNL Graduate School of Genome Science and Technology, The University of Tennessee, Knoxville, Tennessee 37996, USA.
Leaves and flowers are produced by the shoot apical meristem (SAM) at a certain distance from its center, a process that requires the hormone auxin. The amount of auxin and the pattern of its distribution in the initiation zone determine the size and spatial arrangement of organ primordia. Auxin gradients in the SAM are formed by PIN-FORMED (PIN) auxin efflux carriers whose polar localization in the plasma membrane depends on the protein kinase PINOID (PID). Previous work determined that ERECTA (ER) family genes (ERfs) control initiation of leaves. ERfs are plasma membrane receptors that enable cell-to-cell communication by sensing extracellular small proteins from the EPIDERMAL PATTERNING FACTOR/EPF-LIKE (EPF/EPFL) family. Here, we investigated whether ERfs regulate initiation of organs by altering auxin distribution or signaling in Arabidopsis (Arabidopsis thaliana). Genetic and pharmacological data suggested that ERfs do not regulate organogenesis through PINs while transcriptomics data showed that ERfs do not alter primary transcriptional responses to auxin. Our results indicated that in the absence of ERf signaling the peripheral zone cells inefficiently initiate leaves in response to auxin signals and that increased accumulation of auxin in the er erecta-like1 (erl1) erl2 SAM can partially rescue organ initiation defects. We propose that both auxin and ERfs are essential for leaf initiation and that they have common downstream targets. Genetic data also indicated that the role of PID in initiation of cotyledons and leaves cannot be attributed solely to regulation of PIN polarity and PID is likely to have other functions in addition to regulation of auxin distribution.
PMID: 35703946
Plant Physiol , IF:8.34 , 2022 Aug , V190 (1) : P226-237 doi: 10.1093/plphys/kiac266
The Brassicaceae genome resource (TBGR): A comprehensive genome platform for Brassicaceae plants.
School of Life Sciences, North China University of Science and Technology, Tangshan, Hebei 063210, China.; Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China.; School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, China.; Food Science and Technology Department, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA.
The Brassicaceae is an important plant family. We built a user-friendly, web-based, comparative, and functional genomic database, The Brassicaceae Genome Resource (TBGR, http://www.tbgr.org.cn), based on 82 released genomes from 27 Brassicaceae species. The TBGR database contains a large number of important functional genes, including 4,096 glucosinolate genes, 6,625 auxin genes, 13,805 flowering genes, 36,632 resistance genes, 1,939 anthocyanin genes, and 1,231 m6A genes. A total of 1,174,049 specific guide sequences for clustered regularly interspaced short palindromic repeats and 5,856,479 transposable elements were detected in Brassicaceae. TBGR also provides information on synteny, duplication, and orthologs for 27 Brassicaceae species. The TBGR database contains 1,183,851 gene annotations obtained using the TrEMBL, Swiss-Prot, Nr, GO, and Pfam databases. The BLAST, Synteny, Primer Design, Seq_fetch, and JBrowse tools are provided to help users perform comparative genomic analyses. All the genome assemblies, gene models, annotations, and bioinformatics results can be easily downloaded from the TBGR database. We plan to improve and continuously update the database with newly assembled genomes and comparative genomic studies. We expect the TBGR database to become a key resource for the study of the Brassicaceae.
PMID: 35670735
Plant Physiol , IF:8.34 , 2022 Sep , V190 (2) : P1365-1383 doi: 10.1093/plphys/kiac245
Ethylene augments root hypoxia tolerance via growth cessation and reactive oxygen species amelioration.
Plant-Environment Signaling, Institute of Environmental Biology, Utrecht University, Utrecht, 3584 CH, The Netherlands.; Department of Botany and Plant Biology, University of Geneva, Geneva 1211, Switzerland.; Plant Environmental Signalling and Development, Faculty of Biology, University of Freiburg, Freiburg 79104, Germany.; CIBSS-Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg 79104, Germany.; Plant Sciences and the Bioeconomy, Rothamsted Research, Harpenden AL5 2JQ, UK.; Department of Botany and Plant Sciences, Center for Plant Cell Biology, University of California, Riverside, California 92521, USA.; Intelligent Data Ecosystems, Rothamsted Research, Harpenden AL5 2JQ, UK.
Flooded plants experience impaired gas diffusion underwater, leading to oxygen deprivation (hypoxia). The volatile plant hormone ethylene is rapidly trapped in submerged plant cells and is instrumental for enhanced hypoxia acclimation. However, the precise mechanisms underpinning ethylene-enhanced hypoxia survival remain unclear. We studied the effect of ethylene pretreatment on hypoxia survival of Arabidopsis (Arabidopsis thaliana) primary root tips. Both hypoxia itself and re-oxygenation following hypoxia are highly damaging to root tip cells, and ethylene pretreatments reduced this damage. Ethylene pretreatment alone altered the abundance of transcripts and proteins involved in hypoxia responses, root growth, translation, and reactive oxygen species (ROS) homeostasis. Through imaging and manipulating ROS abundance in planta, we demonstrated that ethylene limited excessive ROS formation during hypoxia and subsequent re-oxygenation and improved oxidative stress survival in a PHYTOGLOBIN1-dependent manner. In addition, we showed that root growth cessation via ethylene and auxin occurred rapidly and that this quiescence behavior contributed to enhanced hypoxia tolerance. Collectively, our results show that the early flooding signal ethylene modulates a variety of processes that all contribute to hypoxia survival.
PMID: 35640551
Plant Physiol , IF:8.34 , 2022 Aug , V190 (1) : P113-126 doi: 10.1093/plphys/kiac251
Auxin-driven ecophysiological diversification of leaves in domesticated tomato.
Departamento de Biologia Vegetal, Universidade Federal de Vicosa, 36570-900 Vicosa, Minas Gerais, Brazil.; Departamento de Botanica, Instituto de Biociencias, Universidade de Sao Paulo, 05508-090 Sao Paulo, Brazil.; Departamento de Botanica, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte, Minas Gerais, Brazil.; Centro de Energia Nuclear na Agricultura, Universidade de Sao Paulo, 13400-970 Piracicaba, Sao Paulo, Brazil.; Bioinformatics Multidisciplinary Environment, Instituto Metropole Digital, Universidade Federal Do Rio Grande Do Norte, 59078-400 Natal, Rio Grande do Norte, Brazil.; Laboratory of Hormonal Control of Plant Development, Departamento de Ciencias Biologicas (LCB), Escola Superior de Agricultura "Luiz de Queiroz," Universidade de Sao Paulo, CP 09, 13418-900 Piracicaba, Sao Paulo, Brazil.
Heterobaric leaves have bundle sheath extensions (BSEs) that compartmentalize the parenchyma, whereas homobaric leaves do not. The presence of BSEs affects leaf hydraulics and photosynthetic rate. The tomato (Solanum lycopersicum) obscuravenosa (obv) mutant lacks BSEs. Here, we identify the obv gene and the causative mutation, a nonsynonymous amino acid change that disrupts a C2H2 zinc finger motif in a putative transcription factor. This mutation exists as a polymorphism in the natural range of wild tomatoes but has increased in frequency in domesticated tomatoes, suggesting that the latter diversified into heterobaric and homobaric leaf types. The obv mutant displays reduced vein density, leaf hydraulic conductance and photosynthetic assimilation rate. We show that these and other pleiotropic effects on plant development, including changes in leaf insertion angle, leaf margin serration, minor vein density, and fruit shape, are controlled by OBV via changes in auxin signaling. Loss of function of the transcriptional regulator AUXIN RESPONSE FACTOR 4 (ARF4) also results in defective BSE development, revealing an additional component of a genetic module controlling aspects of leaf development important for ecological adaptation and subject to breeding selection.
PMID: 35639975
Environ Pollut , IF:8.071 , 2022 Nov , V312 : P120084 doi: 10.1016/j.envpol.2022.120084
Chromium in plant growth and development: Toxicity, tolerance and hormesis.
CONACYT-Instituto de Investigaciones Quimico-Biologicas, Universidad Michoacana de San Nicolas de Hidalgo, Edificio B3, Ciudad Universitaria, C.P. 58030, Morelia, Michoacan, Mexico.; Instituto de Investigaciones Quimico-Biologicas, Universidad Michoacana de San Nicolas de Hidalgo, Edificio B3, Ciudad Universitaria, C.P. 58030, Morelia, Michoacan, Mexico.; Instituto de Investigaciones Quimico-Biologicas, Universidad Michoacana de San Nicolas de Hidalgo, Edificio B3, Ciudad Universitaria, C.P. 58030, Morelia, Michoacan, Mexico. Electronic address: jbucio@umich.mx.
Research over the last three decades showed that chromium, particularly the oxyanion chromate Cr(VI) behaves as a toxic environmental pollutant that strongly damages plants due to oxidative stress, disruption of nutrient uptake, photosynthesis and metabolism, and ultimately, represses growth and development. However, mild Cr(VI) concentrations promote growth, induce adventitious root formation, reinforce the root cap, and produce twin roots from single root meristems under conditions that compromise cell viability, indicating its important role as a driver for root organogenesis. In recent years, considerable advance has been made towards deciphering the molecular mechanisms for root sensing of chromate, including the identification of regulatory proteins such as SOLITARY ROOT and MEDIATOR 18 that orchestrate the multilevel dynamics of the oxyanion. Cr(VI) decreases the expression of several glutamate receptors, whereas amino acids such as glutamate, cysteine and proline confer protection to plants from hexavalent chromium stress. The crosstalk between plant hormones, including auxin, ethylene, and jasmonic acid enables tissues to balance growth and defense under Cr(VI)-induced oxidative damage, which may be useful to better adapt crops to biotic and abiotic challenges. The highly contrasting responses of plants manifested at the transcriptional and translational levels depend on the concentration of chromate in the media, and fit well with the concept of hormesis, an adaptive mechanism that primes plants for resistance to environmental challenges, toxins or pollutants. Here, we review the contrasting facets of Cr(VI) in plants including the cellular, hormonal and molecular aspects that mechanistically separate its toxic effects from biostimulant outputs.
PMID: 36057328
PLoS Biol , IF:8.029 , 2022 Sep , V20 (9) : Pe3001781 doi: 10.1371/journal.pbio.3001781
Leaf vein patterning is regulated by the aperture of plasmodesmata intercellular channels.
Department of Biological Sciences, University of Alberta, Edmonton, Canada.
To form tissue networks, animal cells migrate and interact through proteins protruding from their plasma membranes. Plant cells can do neither, yet plants form vein networks. How plants do so is unclear, but veins are thought to form by the coordinated action of the polar transport and signal transduction of the plant hormone auxin. However, plants inhibited in both pathways still form veins. Patterning of vascular cells into veins is instead prevented in mutants lacking the function of the GNOM (GN) regulator of auxin transport and signaling, suggesting the existence of at least one more GN-dependent vein-patterning pathway. Here we show that in Arabidopsis such a pathway depends on the movement of auxin or an auxin-dependent signal through plasmodesmata (PDs) intercellular channels. PD permeability is high where veins are forming, lowers between veins and nonvascular tissues, but remains high between vein cells. Impaired ability to regulate PD aperture leads to defects in auxin transport and signaling, ultimately leading to vein patterning defects that are enhanced by inhibition of auxin transport or signaling. GN controls PD aperture regulation, and simultaneous inhibition of auxin signaling, auxin transport, and regulated PD aperture phenocopies null gn mutants. Therefore, veins are patterned by the coordinated action of three GN-dependent pathways: auxin signaling, polar auxin transport, and movement of auxin or an auxin-dependent signal through PDs. Such a mechanism of tissue network formation is unprecedented in multicellular organisms.
PMID: 36166438
Sci Total Environ , IF:7.963 , 2022 Sep , V855 : P158888 doi: 10.1016/j.scitotenv.2022.158888
Regulation of rhizospheric microbial network to enhance plant growth and resist pollutants: Unignorable weak electric field.
MOE Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, No. 38 Tongyan Road, Jinnan District, Tianjin 300350, China.; College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.; MOE Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, No. 38 Tongyan Road, Jinnan District, Tianjin 300350, China. Electronic address: tianli1@nankai.edu.cn.
The union of Plant Growth-Promoting Bacteria (PGPB) and rhizosphere confers a series of functions beneficial to plant. However, the lack of an opearable in situ method limits the further understanding on the mechanism. In this study, a weak electric field was designed to regulate rhizospheric microflora in a constructed root-splitting reactor. Compared with the control, the aboveground and underground biomass of rice seedling increased by 17 % and 18 % (p < 0.05) respectively under the exist of weak electric field of 0.14 V/cm. The joint action of rhizosphere and PGPB displayed the detoxification ability in the condition of soluble petroleum hydrocarbons, where the height, stem diameter, biomass and root vigor of the plant was increased by 58 %, 32 %, 43 % and 48 % respectively than the control. The selective reproduction of endophytes and ectophytes (denitrifying, auxin-producing, hydrocarbon-degrading and electroactive bacteria) was observed under applied weak electric field, which enhanced the nitrogen utilization, cellular metabolic activity and resistance to toxic organics of plant. This was further confirmed by the up-regulated OTUs related to the hydrocarbon degradation function, tryptophan metabolism and metabolism of nicotinate and nicotinamide. Moreover, the weak electric field also enhanced the transfer ability of partial endophytes grown in the root to improve plant stress resistance. The results in this work inspired an exercisable method for in situ enrichment of PGPB in the rhizosphere to cope with food crisis and provided a new way to deal with sudden environmental events.
PMID: 36165908
Sci Total Environ , IF:7.963 , 2022 Aug , V851 (Pt 2) : P158287 doi: 10.1016/j.scitotenv.2022.158287
Perfluorooctanoic acid and perfluorooctane sulfonic acid inhibit plant growth through the modulation of phytohormone signalling pathways: Evidence from molecular and genetic analysis in Arabidopsis.
College of Horticulture, Shanxi Agricultural University, Taigu 030801, China.; College of Horticulture, Shanxi Agricultural University, Taigu 030801, China. Electronic address: xujin@sxau.edu.cn.
Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are the most representative perfluoroalkyl substances that accumulate in the food chain and are harmful to the environment. The uptake, translocation and physiological effects of PFOA and PFOS in plants have been reported in recent years; however, the regulatory mechanisms underlying PFOA- and PFOS-mediated plant growth and development remain largely unclear. Here, using Arabidopsis thaliana as the study material, we showed that both PFOA and PFOS inhibited plant growth; PFOS showed a stronger inhibitory effect on primary root (PR) growth, whereas PFOA exerted a stronger inhibitory effect on photosynthesis. Transcriptome analysis revealed that PFOA- and PFOS-modulated plant growth and development were correlated with the phytohormones auxin and abscisic acid (ABA). Further genetic analyses using mutants related to auxin biosynthesis, receptors and transport and mutants related to ABA biosynthesis and signalling transduction revealed that both PFOA and PFOS inhibited PR growth by modulating auxin biosynthesis and signalling pathways, and the ABA signalling pathway was also involved in PFOS-mediated PR growth inhibition. Collectively, these results shed new light on the molecular mechanisms of PFOA- and PFOS-mediated root system growth and their effects on phytohormone signalling pathways in plants.
PMID: 36030856
Curr Opin Plant Biol , IF:7.834 , 2022 Oct , V69 : P102293 doi: 10.1016/j.pbi.2022.102293
Reactive oxygen species function as signaling molecules in controlling plant development and hormonal responses.
Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC, 27101, USA; Department of Biology and the Center for Molecular Signaling, Wake Forest University, Winston-Salem, NC, 27109, USA.; Department of Biology and the Center for Molecular Signaling, Wake Forest University, Winston-Salem, NC, 27109, USA.; Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC, 27101, USA; Department of Biology and the Center for Molecular Signaling, Wake Forest University, Winston-Salem, NC, 27109, USA. Electronic address: muday@wfu.edu.
Reactive oxygen species (ROS) serve as second messengers in plant signaling pathways to remodel plant growth and development. New insights into how enzymatic ROS-producing machinery is regulated by hormones or localized during development have provided a framework for understanding the mechanisms that control ROS accumulation patterns. Signaling-mediated increases in ROS can then modulate the activity of proteins through reversible oxidative modification of specific cysteine residues. Plants also control the synthesis of antioxidants, including plant-specialized metabolites, to further define when, where, and how much ROS accumulate. The availability of sophisticated imaging capabilities, combined with a growing tool kit of ROS detection technologies, particularly genetically encoded biosensors, sets the stage for improved understanding of ROS as signaling molecules.
PMID: 36099672
Plant Cell Environ , IF:7.228 , 2022 Sep doi: 10.1111/pce.14438
Homeobox transcription factors OsZHD1 and OsZHD2 induce inflorescence meristem activity at floral transition in rice.
Department of Plant Bioscience, College of Natural Resources and Life Science, Pusan National University, Miryang, Republic of Korea.; Life and Industry Convergence Research Institute, Pusan National University, Miryang, Republic of Korea.; Graduate School of Biotechnology and Crop Biotech Institute, Kyung Hee University, Yongin, Republic of Korea.
Floral transition starts in the leaves when florigens respond to various environmental and developmental factors. Among several regulatory genes that are preferentially expressed in the inflorescence meristem during the floral transition, this study examines the homeobox genes OsZHD1 and OsZHD2 for their roles in regulating this transition. Although single mutations in these genes did not result in visible phenotype changes, double mutations in these genes delayed flowering. Florigen expression was not altered in the double mutants, indicating that the delay was due to a defect in florigen signaling. Morphological analysis of shoot apical meristem at the early developmental stage indicated that inflorescence meristem development was significantly delayed in the double mutants. Overexpression of ZHD2 causes early flowering because of downstream signals after the generation of florigens. Expression levels of the auxin biosynthesis genes were reduced in the mutants and the addition of indole-3-acetic acid recovered the defect in the mutants, suggesting that these homeobox genes play a role in auxin biosynthesis. A rice florigen, RICE FLOWERING LOCUS T 1, binds to the promoter regions of homeobox genes. These results indicate that florigens stimulate the expression of homeobox genes, enhancing inflorescence development in the shoot apex.
PMID: 36120845
Plant Cell Environ , IF:7.228 , 2022 Sep doi: 10.1111/pce.14434
Auxin plays a role in the adaptation of rice to anaerobic germination and seedling establishment.
Department of Bioagricultural Sciences, National Chiayi University, Chiayi, Taiwan.; Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan.
Auxin is well known to stimulate coleoptile elongation and rapid seedling growth in the air. However, its role in regulating rice germination and seedling establishment under submergence is largely unknown. Previous studies revealed that excessive levels of indole-3-acetic acid(IAA) frequently cause the inhibition of plant growth and development. In this study, the high-level accumulation of endogenous IAA is observed under dark submergence, stimulating rice coleoptile elongation but limiting the root and primary leaf growth during anaerobic germination (AG). We found that oxygen and light can reduce IAA levels, promote the seedling establishment and enhance rice AG tolerance. miRNA microarray profiling and RNA gel blot analysis results show that the expression of miR167 is negatively regulated by submergence; it subsequently modulates the accumulation of free IAA through the miR167-ARF-GH3 pathway. The OsGH3-8 encodes an IAA-amido synthetase that functions to prevent free IAA accumulation. Reduced miR167 levels or overexpressing OsGH3-8 increase auxin metabolism, reduce endogenous levels of free IAA and enhance rice AG tolerance. Our studies reveal that poor seed germination and seedling growth inhibition resulting from excessive IAA accumulation would cause intolerance to submergence in rice, suggesting that a certain threshold level of auxin is essential for rice AG tolerance.
PMID: 36071575
Microbiol Spectr , IF:7.171 , 2022 Aug , V10 (4) : Pe0081022 doi: 10.1128/spectrum.00810-22
Impact of Phyllosphere Methylobacterium on Host Rice Landraces.
National Center for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, India.
The genus Methylobacterium includes widespread plant-associated bacteria that are abundant in the plant phyllosphere (leaf surfaces), consume plant-secreted methanol, and can produce plant growth-promoting metabolites. However, despite the potential to increase agricultural productivity, their impact on host fitness in the natural environment is relatively poorly understood. Here, we conducted field experiments with three traditionally cultivated rice landraces from northeastern India. We inoculated seedlings with native versus nonnative phyllosphere Methylobacterium strains and found significant impacts on plant growth and grain yield. However, these effects were variable. Whereas some Methylobacterium isolates were beneficial for their host, others had no impact or were no more beneficial than the bacterial growth medium on its own. Host plant benefits were not consistently associated with Methylobacterium colonization and did not have altered phyllosphere microbiome composition, changes in the early expression of plant stress response pathways, or bacterial auxin production. We provide the first demonstration of the benefits of phyllosphere Methylobacterium for rice yield under field conditions and highlight the need for further analysis to understand the mechanisms underlying these benefits. Given that the host landrace-Methylobacterium relationship was not generalizable, future agricultural applications will require careful testing to identify coevolved host-bacterium pairs that may enhance the productivity of high-value rice varieties. IMPORTANCE Plants are associated with diverse microbes in nature. Do the microbes increase host plant health, and can they be used for agricultural applications? This is an important question that must be answered in the field rather than in the laboratory or greenhouse. We tested the effects of native, leaf-inhabiting bacteria (genus Methylobacterium) on traditionally cultivated rice varieties in a crop field. We found that inoculation with some bacteria increased rice grain production substantially while a nonnative bacterium reduced plant health. Overall, the effect of bacterial inoculation varied across pairs of rice varieties and their native bacteria. Thus, knowledge of evolved associations between specific bacteria hosted by specific rice varieties is necessary to develop ways to increase the yield of traditional rice landraces and preserve these important sources of cultural and genetic diversity.
PMID: 35856668
J Integr Plant Biol , IF:7.061 , 2022 Sep doi: 10.1111/jipb.13366
TMK1-mediated auxin signal regulates membrane-associated clathrin in Arabidopsis roots.
Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China.; College of Life Sciences, Shaoxing University, Shaoxing, 312000, Zhejiang, China.
Clathrin-mediated endocytosis (CME) is the major endocytic pathway in eukaryotic cells that directly regulates abundance of plasma membrane (PM) proteins. Clathrin triskelia are composed of clathrin heavy chains (CHCs) and light chains (CLCs), and the phytohormone auxin differentially regulates membrane-associated CLCs and CHCs, modulating the endocytosis and therefore the distribution of auxin efflux transporter PIN-FORMED2 (PIN2). However, the molecular mechanisms by which auxin regulates clathrin are still poorly understood. Transmembrane kinase family proteins (TMKs) are considered to contribute to auxin signaling and plant development, it remains unclear whether they are involved in PIN transport by CME. We assessed TMKs involvement in the regulation of clathrin by auxin, using genetic, pharmacological, and cytological approaches including live-cell imaging and immunofluorescence. In tmk1 mutant seedlings, auxin failed to rapidly regulate abundance of both CHC and CLC and to inhibit PIN2 endocytosis, leading to an impaired asymmetric distribution of PIN2 and therefore auxin. Furthermore, TMK3 and TMK4 were shown not involved in regulation of clathrin by auxin. In summary, TMK1 is essential for auxin-regulated clathrin recruitment and CME. TMK1 therefore plays a critical role in the establishment of an asymmetric distribution of PIN2 and an auxin gradient during root gravitropism. This article is protected by copyright. All rights reserved.
PMID: 36114789
J Integr Plant Biol , IF:7.061 , 2022 Sep doi: 10.1111/jipb.13365
Cowpea NAC1/NAC2 transcription factors improved growth and tolerance to drought and heat in transgenic cowpea through combined activation of photosynthetic and antioxidant mechanisms.
Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Assam, 781039, India.; Faculty of Applied Biological Sciences, Gifu University, 1-1, Yanagido, Gifu, 501-1193, Japan.
NAC transcription factors (TFs) are central switches of growth and stress responses in plants. However, unpredictable interspecies conservation of function and regulatory targets makes the well-studied NAC orthologs inapt for pulse engineering. The knowledge of suitable NAC candidates in hardy pulses like cowpea (Vigna unguiculata (L.) Walp.) is still in infancy, hence warrants immediate biotechnological intervention. Here, we showed that overexpression of two native NAC genes (VuNAC1 and VuNAC2) promoted germinative, vegetative, and reproductive growth and conferred multiple abiotic stress tolerance in a commercial cowpea variety. The transgenic lines displayed increased leaf area, thicker stem, nodule-rich denser root system, early flowering, higher pod production ( approximately 3.2-fold and approximately 2.1-fold), and greater seed weight (10.3% and 6.0%). In contrast, transient suppression of VuNAC1/2 caused severe growth retardation and flower inhibition. The overexpressor lines showed remarkable tolerance to major yield-declining terminal stresses, such as drought, salinity, heat, and cold, and recovered growth and seed production by boosting photosynthetic activity, water-use efficiency, membrane-integrity, Na+/K+ homeostasis, and antioxidant activity. The comparative transcriptome study indicated consolidated activation of genes involved in chloroplast development, photosynthetic complexes, cell division and expansion, cell-wall biogenesis, nutrient uptake and metabolism, stress-response, ABA, and auxin signaling. Unlike their orthologs, VuNAC1/2 direct synergistic transcriptional tuning of stress and developmental signaling to avoid unwanted trade-offs. Their overexpression governs the favorable interplay of photosynthesis and ROS regulation to improve stress recovery, nutritional sufficiency, biomass, and production. This unconventional balance of strong stress tolerance and agronomic quality is useful for translational crop research and molecular breeding of pulses. This article is protected by copyright. All rights reserved.
PMID: 36107155
J Integr Plant Biol , IF:7.061 , 2022 Aug doi: 10.1111/jipb.13347
The SlTPL3-SlWUS module regulates multi-locule formation in tomato by modulating auxin and gibberellin levels in the shoot apical meristem.
Key Laboratory of Horticultural Crop Biology and Germplasm Innovation in South China, Ministry of Agriculture, College of Horticulture, South China Agricultural University, Guangzhou, 510642, China.; Laboratory of Genomics and Biotechnology of Fruits, INRA, Toulouse INP, University of Toulouse, Castanet Tolosan, F-31326, France.
Malformed fruits depreciate a plant's market value. In tomato (Solanum lycopersicum), fruit malformation is associated with the multi-locule trait, which involves genes regulating shoot apical meristem (SAM) development. The expression pattern of TOPLESS3 (SlTPL3) throughout SAM development prompted us to investigate its functional significance via RNA interference (RNAi) and clustered regularly interspaced short palindromic repeats/CRISPR-associated nuclease 9 (Cas9)-mediated gene editing. Lower SlTPL3 transcript levels resulted in larger fruits with more locules and larger SAMs at the 5 d after germination (DAG5) stage. Differentially expressed genes in the SAM of wild-type (WT) and SlTPL3-RNAi plants, identified by transcriptome deep sequencing (RNA-seq), were enriched in the gibberellin (GA) biosynthesis and plant hormone signaling pathways. Moreover, exogenous auxin and paclobutrazol treatments rescued the multi-locule phenotype, indicating that SlTPL3 affects SAM size by mediating auxin and GA levels in the SAM. Furthermore, SlTPL3 interacted with WUSCHEL (SlWUS), which plays an important role in SAM size maintenance. We conducted RNA-seq and DNA affinity purification followed by sequencing (DAP-seq) analyses to identify the genes regulated by SlTPL3 and SlWUS in the SAM and to determine how they regulate SAM size. We detected 24 overlapping genes regulated by SlTPL3 and SlWUS and harboring an SlWUS-binding motif in their promoters. Furthermore, functional annotation revealed a notable enrichment for functions in auxin transport, auxin signal transduction, and GA biosynthesis. Dual-luciferase assays also revealed that SlTPL3 enhances SlWUS-mediated regulation (repression and activation) of SlPIN3 and SlGA2ox4 transcription, indicating that the SlTPL3-SlWUS module regulates SAM size by mediating auxin distribution and GA levels, and perturbations of this module result in enlarged SAM. These results provide novel insights into the molecular mechanism of SAM maintenance and locule formation in tomato and highlight the SlTPL3-SlWUS module as a key regulator.
PMID: 35980297
J Integr Plant Biol , IF:7.061 , 2022 Aug doi: 10.1111/jipb.13341
The unconventional prefoldin RPB5 interactor mediates the gravitropic response by modulating cytoskeleton organization and auxin transport in Arabidopsis.
State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Daizong Street 61, Tai'an, 271018, China.; Shandong Provincial Key Laboratory of Biophysics, Institute of Biophysics, Dezhou University, Dezhou, 253023, China.; Sino-German Joint Research Center on Agricultural Biology, College of Life Sciences, Shandong Agricultural University, Daizong Street 61, Tai'an, 271018, China.; Faculty of Biology, Institute of Biology II/Molecular Plant Physiology, Albert-Ludwigs-University of Freiburg, Schanzlestrasse 1, Freiburg, D-79104, Germany.; National Key Laboratory of Plant Molecular Genetics (NKLPMG), CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology (SIPPE), Chinese Academy of Sciences (CAS), Shanghai, 200032, China.; Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.; Key Laboratory of Plant Molecular Physiology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.; University of Chinese Academy of Sciences, Beijing, 100049, China.
Gravity-induced root curvature involves the asymmetric distribution of the phytohormone auxin. This response depends on the concerted activities of the auxin transporters such as PIN-FORMED (PIN) proteins for auxin efflux and AUXIN RESISTANT 1 (AUX1) for auxin influx. However, how the auxin gradient is established remains elusive. Here we identified a new mutant with a short root, strong auxin distribution in the lateral root cap and an impaired gravitropic response. The causal gene encoded an Arabidopsis homolog of the human unconventional prefoldin RPB5 interactor (URI). AtURI interacted with prefoldin 2 (PFD2) and PFD6, two beta-type PFD members that modulate actin and tubulin patterning in roots. The auxin reporter DR5rev :GFP showed that asymmetric auxin redistribution after gravistimulation is disordered in aturi-1 root tips. Treatment with the endomembrane protein trafficking inhibitor brefeldin A indicated that recycling of the auxin transporter PIN2 is disrupted in aturi-1 roots as well as in pfd mutants. We propose that AtURI cooperates with PFDs to recycle PIN2 and modulate auxin distribution.
PMID: 35943836
J Integr Plant Biol , IF:7.061 , 2022 Aug doi: 10.1111/jipb.13336
FERONIA is involved in phototropin 1-mediated blue light phototropic growth in Arabidopsis.
School of Life Sciences, Central South University, Changsha, 410078, China.; State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha, 410082, China.; Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan University, Changsha, 410082, China.; Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720, USA.; State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha, 410125, China.
Plant shoot phototropism is triggered by the formation of a light-driven auxin gradient leading to bending growth. The blue light receptor phototropin 1 (phot1) senses light direction, but how this leads to auxin gradient formation and growth regulation remains poorly understood. Previous studies have suggested phot1's role for regulated apoplastic acidification, but its relation to phototropin and hypocotyl phototropism is unclear. Herein, we show that blue light can cause phot1 to interact with and phosphorylate FERONIA (FER), a known cell growth regulator, and trigger downstream phototropic bending growth in Arabidopsis hypocotyls. fer mutants showed defects in phototropic growth, similar to phot1/2 mutant. FER also interacts with and phosphorylates phytochrome kinase substrates, the phot1 downstream substrates. The phot1-FER pathway acts upstream of apoplastic acidification and the auxin gradient formation in hypocotyl under lateral blue light, both of which are critical for phototropic bending growth in hypocotyls. Our study highlights a pivotal role of FER in the phot1-mediated phototropic cell growth regulation in plants.
PMID: 35924740
J Integr Plant Biol , IF:7.061 , 2022 Sep , V64 (9) : P1803-1820 doi: 10.1111/jipb.13326
Abscisic acid-dependent PMT1 expression regulates salt tolerance by alleviating abscisic acid-mediated reactive oxygen species production in Arabidopsis.
State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.; State Key Laboratory of Subtropical Silviculture, Zhejiang A & F University, Hangzhou, 311300, China.; State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, 510642, China.
Phosphocholine (PCho) is an intermediate metabolite of nonplastid plant membranes that is essential for salt tolerance. However, how PCho metabolism modulates response to salt stress remains unknown. Here, we characterize the role of phosphoethanolamine N-methyltransferase 1 (PMT1) in salt stress tolerance in Arabidopsis thaliana using a T-DNA insertional mutant, gene-editing alleles, and complemented lines. The pmt1 mutants showed a severe inhibition of root elongation when exposed to salt stress, but exogenous ChoCl or lecithin rescued this defect. pmt1 also displayed altered glycerolipid metabolism under salt stress, suggesting that glycerolipids contribute to salt tolerance. Moreover, pmt1 mutants exhibited altered reactive oxygen species (ROS) accumulation and distribution, reduced cell division activity, and disturbed auxin distribution in the primary root compared with wild-type seedlings. We show that PMT1 expression is induced by salt stress and relies on the abscisic acid (ABA) signaling pathway, as this induction was abolished in the aba2-1 and pyl112458 mutants. However, ABA aggravated the salt sensitivity of the pmt1 mutants by perturbing ROS distribution in the root tip. Taken together, we propose that PMT1 is an important phosphoethanolamine N-methyltransferase participating in root development of primary root elongation under salt stress conditions by balancing ROS production and distribution through ABA signaling.
PMID: 35789105
J Exp Bot , IF:6.992 , 2022 Aug doi: 10.1093/jxb/erac336
Genetic modification of PIN genes induces causal mechanisms of stay-green drought adaptation phenotype.
University of Queensland, Queensland Alliance for Agriculture and Food Innovation (QAAFI), Warwick, QLD 4370, Australia.; University of Queensland, QAAFI, Brisbane, QLD 4072, Australia.; Agri-Science Queensland, Department of Agriculture & Fisheries, Warwick, QLD 4370, Australia.; Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA.; Department of Horticultural Sciences, Texas A&M University, College Station, TX 77843, USA.
The stay-green trait is recognised as a key drought adaptation mechanism in cereals worldwide. Stay-green sorghum plants exhibit delayed senescence of leaves and stems, leading to prolonged growth, a reduced risk of lodging and higher grain yield under end-of-season drought stress. More than 45 quantitative trait loci (QTL) associated with stay-green have been identified, including two major QTL (Stg1 and Stg2). However, none of the contributing genes that regulate functional stay-green are known. Here we show that the PIN FORMED family of auxin efflux carriers induce some of the causal mechanisms driving the stay-green phenotype in sorghum, with SbPIN4 and SbPIN2 located in Stg1 and Stg2, respectively. We found that 9 of 11 sorghum PIN genes aligned with known stay-green QTL. In transgenic studies, we demonstrated that PIN genes located within the Stg1 (SbPIN4), Stg2 (SbPIN2) and Stg3b (SbPIN1) QTL regions acted pleiotropically to modulate canopy development, root architecture and panicle growth in sorghum, with SbPIN1, SbPIN2 and SbPIN4 differentially expressed in various organs relative to the non stay-green control. The emergent consequence of such modifications in canopy and root architecture is a stay-green phenotype. Crop simulation modelling shows that the SbPIN2 phenotype can increase grain yield under drought.
PMID: 35961690
J Exp Bot , IF:6.992 , 2022 Aug , V73 (14) : P4612-4614 doi: 10.1093/jxb/erac238
How do plant roots overcome physical barriers?
Triticeae Research Institute, Sichuan Agricultural University, 611130 Chengdu, China.; Key Laboratory of Plant-Soil Interactions, MOE, College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, China Agricultural University, 100193 Beijing, China.; Molecular Plant Nutrition, Department of Physiology and Cell Biology, Leibniz Institute of Plant Genetics and Crop Plant Research, D-06466 Gatersleben, Germany.
PMID: 35950462
J Exp Bot , IF:6.992 , 2022 Aug doi: 10.1093/jxb/erac318
GmHY2a encodes a phytochromobilin synthase that regulates internode length and flowering time in soybean.
Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Changchun 130012, China.; University of Chinese Academy of Sciences, Beijing 100049, China.
Plant height and flowering time are important agronomic traits that directly affect soybean [Glycine max (L.) Merr.] adaptability and yield. Here, the Glycine max long internode 1 (Gmlin1) mutant was selected from an ethyl methyl sulfonate (EMS)-mutated Williams 82 population due to its long internodes and early flowering. Using bulked segregant analysis (BSA), the Gmlin1 locus was mapped to Glyma.02G304700, a homologue of the Arabidopsis HY2 gene, which encodes a phytochromobilin (PPhiB) synthase involved in phytochrome chromophore synthesis. Mutation of GmHY2a resulted in failure of the de-etiolation response under both red and far-red light. The Gmlin1 mutant exhibits a constitutive shade avoidance response under normal light, and the mutations influence the auxin and gibberellin pathways to promote internode elongation. The Gmlin1 mutant also exhibits decreased photoperiod sensitivity. In addition, the soybean photoperiod repressor gene E1 is downregulated in the Gmlin1 mutant, resulting in accelerated flowering. The nuclear import of phytochrome A (GmphyA) and GmphyB following light treatment was decreased in Gmlin1 protoplasts, indicating that the weak light response of the Gmlin1 mutant is caused by a decrease in functional phytochrome. Together, these results indicate that GmHY2a plays an important role in soybean phytochrome biosynthesis and provide insights into the adaptability of the soybean plant.
PMID: 35946571
J Exp Bot , IF:6.992 , 2022 Aug doi: 10.1093/jxb/erac326
The protein phosphatase 2A catalytic subunit StPP2Ac2b is involved in the control of potato tuber sprouting and source-sink balance in tubers and sprouts.
Instituto de Investigaciones en Ingenieria Genetica y Biologia Molecular "Dr. Hector Torres", Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET). Vuelta de Obligado 2490, C1428ADN Buenos Aires, Argentina.
Sprouting negatively affects the quality of stored potato tubers. Understanding the molecular mechanisms that control this process is important for the development of potato varieties with desired sprouting characteristics. The serine/threonine protein phosphatase type 2A (PP2A) has been implicated in several developmental programs and stress responses in plants. PP2A comprises a catalytic (PP2Ac), a scaffolding (A) and a regulatory (B) subunit. In cultivated potato, six PP2Ac isoforms were identified, named StPP2Ac1, 2a, 2b, 3, 4 and 5. In this study we evaluated the sprouting behavior of potato tubers overexpressing the catalytic subunit 2b (StPP2Ac2b-OE). The onset of sprouting and initial sprout elongation is significantly delayed in StPP2Ac2b-OE tubers; however, sprout growth is accelerated during the late stages of development, due to a high degree of branching. StPP2Ac2b-OE tubers also exhibit a pronounced loss of apical dominance. These developmental characteristics are accompanied by changes in carbohydrate metabolism and response to gibberellic acid, and a differential balance between abscisic acid, gibberellic acid, cytokinins and auxin. Overexpression of StPP2Ac2b alters the source-sink balance, increasing the source capacity of the tuber, and the sink strength of the sprout to support its accelerated growth.
PMID: 35925650
J Exp Bot , IF:6.992 , 2022 Sep , V73 (16) : P5758-5772 doi: 10.1093/jxb/erac228
In vitro functional characterization predicts the impact of bacterial root endophytes on plant growth.
Department of Botany and Plant Pathology, Center for Plant Biology, Purdue University, West Lafayette, IN, USA.
Utilizing beneficial microbes for crop improvement is one strategy to achieve sustainable agriculture. However, identifying microbial isolates that promote crop growth is challenging, in part because using bacterial taxonomy to predict an isolate's effect on plant growth may not be reliable. The overall aim of this work was to determine whether in vitro functional traits of bacteria were predictive of their in planta impact. We isolated 183 bacterial endophytes from field-grown roots of two tomato species, Solanum lycopersicum and S. pimpinellifolium. Sixty isolates were screened for six in vitro functional traits: auxin production, siderophore production, phosphate solubilization, antagonism to a soilborne pathogen, and the presence of two antimicrobial metabolite synthesis genes. Hierarchical clustering of the isolates based on the in vitro functional traits identified several groups of isolates sharing similar traits. We called these groups 'functional groups'. To understand how in vitro functional traits of bacteria relate to their impact on plants, we inoculated three isolates from each of the functional groups on tomato seedlings. Isolates within the same functional group promoted plant growth at similar levels, regardless of their host origin or taxonomy. Together, our results demonstrate the importance of examining root endophyte functions for improving crop production.
PMID: 35596672
J Exp Bot , IF:6.992 , 2022 Aug , V73 (14) : P4832-4849 doi: 10.1093/jxb/erac187
From fruit growth to ripening in plantain: a careful balance between carbohydrate synthesis and breakdown.
Biosystems Department, KULeuven, 3001 Leuven, Belgium.; INRAE, Fruit Biology and Pathology, Universite De Bordeaux, UMR 1332, 33140 Villenave d'Ornon, France.; IITA, Crop Breeding, Ibadan 200001, Oyo State, Nigeria.; IITA, Crop Breeding, PO Box 7878, Kampala, Uganda.; Bioversity International, Biodiversity for Food and Agriculture, 3001 Leuven, Belgium.; SYBIOMA, KULeuven, 3001 Leuven, Belgium.
In this study, we aimed to investigate for the first time different fruit development stages in plantain banana in order gain insights into the order of appearance and dominance of specific enzymes and fluxes. We examined fruit development in two plantain banana cultivars during the period between 2-12 weeks after bunch emergence using high-throughput proteomics, quantification of major metabolites, and analyses of metabolic fluxes. Starch synthesis and breakdown are processes that take place simultaneously. During the first 10 weeks fruits accumulated up to 48% of their dry weight as starch, and glucose 6-phosphate and fructose were important precursors. We found a unique amyloplast transporter and hypothesize that it facilitates the import of fructose. We identified an invertase originating from the Musa balbisiana genome that would enable carbon flow back to growth and starch synthesis and maintain a high starch content even during ripening. Enzymes associated with the initiation of ripening were involved in ethylene and auxin metabolism, starch breakdown, pulp softening, and ascorbate biosynthesis. The initiation of ripening was cultivar specific, with faster initiation being particularly linked to the 1-aminocyclopropane-1-carboxylate oxidase and 4-alpha glucanotransferase disproportionating enzymes. Information of this kind is fundamental to determining the optimal time for picking the fruit in order to reduce post-harvest losses, and has potential applications for breeding to improve fruit quality.
PMID: 35512676
J Exp Bot , IF:6.992 , 2022 Aug , V73 (14) : P4716-4732 doi: 10.1093/jxb/erac188
ROOT PENETRATION INDEX 3, a major quantitative trait locus associated with root system penetrability in Arabidopsis.
Unidad de Genomica Avanzada/LANGEBIO, Centro de Investigacion y de Estudios Avanzados, Irapuato, Mexico.; Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC, USA.; Institute of Genomics for Crop Abiotic Stress Tolerance, Department of Plant and Soil Science, Texas Tech University, Lubbock, TX 79409, USA.
Soil mechanical impedance precludes root penetration, confining root system development to shallow soil horizons where mobile nutrients are scarce. Using a two-phase-agar system, we characterized Arabidopsis responses to low and high mechanical impedance at three root penetration stages. We found that seedlings whose roots fail to penetrate agar barriers show a significant reduction in leaf area, root length, and elongation zone and an increment in root diameter, while those capable of penetrating show only minor morphological effects. Analyses using different auxin-responsive reporter lines, exogenous auxins, and inhibitor treatments suggest that auxin responsiveness and PIN-mediated auxin distribution play an important role in regulating root responses to mechanical impedance. The assessment of 21 Arabidopsis accessions revealed that primary root penetrability varies widely among accessions. To search for quantitative trait loci (QTLs) associated to root system penetrability, we evaluated a recombinant inbred population derived from Landsberg erecta (Ler-0, with a high primary root penetrability) and Shahdara (Sha, with a low primary root penetrability) accessions. QTL analysis revealed a major-effect QTL localized in chromosome 3, ROOT PENETRATION INDEX 3 (q-RPI3), which accounted for 29.98% (logarithm of odds=8.82) of the total phenotypic variation. Employing an introgression line (IL-321) with a homozygous q-RPI3 region from Sha in the Ler-0 genetic background, we demonstrated that q-RPI3 plays a crucial role in root penetrability. This multiscale study reveals new insights into root plasticity during the penetration process in hard agar layers, natural variation, and genetic architecture behind primary root penetrability in Arabidopsis.
PMID: 35512438
J Exp Bot , IF:6.992 , 2022 Aug , V73 (14) : P4818-4831 doi: 10.1093/jxb/erac185
Arabidopsis TWISTED DWARF1 regulates stamen elongation by differential activation of ABCB1,19-mediated auxin transport.
University of Fribourg, Department of Biology, CH-1700 Fribourg, Switzerland.; IBPM-CNR, Dipartimento di Biologia e Biotecnologie, Sapienza Universita di Roma, P. le A. Moro 5, 00185 Roma, Italy.
Despite clear evidence that a local accumulation of auxin is likewise critical for male fertility, much less is known about the components that regulate auxin-controlled stamen development. In this study, we analyzed physiological and morphological parameters in mutants of key players of ABCB-mediated auxin transport, and spatially and temporally dissected their expression on the protein level as well as auxin fluxes in the Arabidopsis stamens. Our analyses revealed that the FKBP42, TWISTED DWARF1 (TWD1), promotes stamen elongation and, to a lesser extent, anther dehiscence, as well as pollen maturation, and thus is required for seed development. Most of the described developmental defects in twd1 are shared with the abcb1 abcb19 mutant, which can be attributed to the fact that TWD1-as a described ABCB chaperone-is a positive regulator of ABCB1- and ABCB19-mediated auxin transport. However, reduced stamen number was dependent on TWD1 but not on investigated ABCBs, suggesting additional players downstream of TWD1. We predict an overall housekeeping function for ABCB1 during earlier stages, while ABCB19 seems to be responsible for the key event of rapid elongation at later stages of stamen development. Our data indicate that TWD1 controls stamen development by differential activation of ABCB1,19-mediated auxin transport in the stamen.
PMID: 35512423
Int J Biol Macromol , IF:6.953 , 2022 Aug , V220 : P67-78 doi: 10.1016/j.ijbiomac.2022.08.065
PIN and PILS family genes analyses in Chrysanthemum seticuspe reveal their potential functions in flower bud development and drought stress.
State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Flower Biology and Germplasm Innovation, Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Biology of Ornamental Plants in East China, National Forestry and Grassland Administration, Nanjing Agricultural University, Nanjing 210095, China; College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China.; State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Flower Biology and Germplasm Innovation, Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Biology of Ornamental Plants in East China, National Forestry and Grassland Administration, Nanjing Agricultural University, Nanjing 210095, China; College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: chensm@njau.edu.cn.
Auxin affects almost all plant growth and developmental processes. The PIN-FORMED (PIN) and PIN-LIKES (PILS) family genes determine the direction and distribution gradient of auxin flow by polar localization on the cell membrane. However, there are no systematic studies on PIN and PILS family genes in chrysanthemum. Here, 18 PIN and 13 PILS genes were identified in Chrysanthemum seticuspe. The evolutionary relationships, physicochemical properties, conserved motifs, cis-acting elements, chromosome localization, collinearity, and expression characteristics of these genes were analyzed. CsPIN10a, CsPIN10b, and CsPIN10c are unique PIN genes in C. seticuspe. Expression pattern analysis showed that these genes had different tissue specificities, and the expression levels of CsPIN8, CsPINS1, CsPILS6, and CsPILS10 were linearly related to the developmental period of the flower buds. In situ hybridization assay showed that CsPIN1a, CsPIN1b, and CsPILS8 were expressed in floret primordia and petal tips, and CsPIN1a was specifically expressed in the middle of the bract primordia, which might regulate lateral expansion of the bracts. CsPIN and CsPILS family genes are also involved in drought stress responses. This study provides theoretical support for the cultivation of new varieties with attractive flower forms and high drought tolerance.
PMID: 35970365
Development , IF:6.868 , 2022 Sep , V149 (18) doi: 10.1242/dev.200715
The dynamic proteome in Arabidopsis thaliana early embryogenesis.
State Key Laboratory of Agrobiotechnology and School of Life Science, The Chinese University of Hong Kong, 999077 Hong Kong, China.; Department of Biology, Southern University of Science and Technology, Shenzhen 518055, China.
The morphology of the flowering plant is established during early embryogenesis. In recent years, many studies have focused on transcriptional profiling in plant embryogenesis, but the dynamic landscape of the Arabidopsis thaliana proteome remains elusive. In this study, Arabidopsis embryos at 2/4-cell, 8-cell, 16-cell, 32-cell, globular and heart stages were collected for nanoproteomic analysis. In total, 5386 proteins were identified. Of these, 1051 proteins were universally identified in all developmental stages and a range of 27 to 2154 proteins was found to be stage specific. These proteins could be grouped into eight clusters according to their expression levels. Gene Ontology enrichment analysis showed that genes involved in ribosome biogenesis and auxin-activated signalling were enriched during early embryogenesis, indicating that active translation and auxin signalling are important events in Arabidopsis embryo development. Combining RNA-sequencing data with the proteomics analysis, the correlation between mRNA and protein was evaluated. An overall positive correlation was found between mRNA and protein. This work provides a comprehensive landscape of the Arabidopsis proteome in early embryogenesis. Some important proteins/transcription factors identified through network analysis may serve as potential targets for future investigation.
PMID: 35950926
Cells , IF:6.6 , 2022 Sep , V11 (17) doi: 10.3390/cells11172761
Roles of Auxin in the Growth, Development, and Stress Tolerance of Horticultural Plants.
Key Laboratory of Plant Hormones and Development Regulation of Chongqing, School of Life Sciences, Chongqing University, Chongqing 400044, China.
Auxin, a plant hormone, regulates virtually every aspect of plant growth and development. Many current studies on auxin focus on the model plant Arabidopsis thaliana, or on field crops, such as rice and wheat. There are relatively few studies on what role auxin plays in various physiological processes of a range of horticultural plants. In this paper, recent studies on the role of auxin in horticultural plant growth, development, and stress response are reviewed to provide novel insights for horticultural researchers and cultivators to improve the quality and application of horticultural crops.
PMID: 36078168
Cells , IF:6.6 , 2022 Aug , V11 (17) doi: 10.3390/cells11172652
Auxin Regulates Apical Stem Cell Regeneration and Tip Growth in the Marine Red Alga Neopyropia yezoensis.
Graduate School of Fisheries Sciences, Hokkaido University, 3-1-1 Minato-cho, Hakodate 041-8611, Japan.; School of Fisheries Sciences, Hokkaido University, 3-1-1 Minato-cho, Hakodate 041-8611, Japan.; Faculty of Bio-Industry, Tokyo University of Agriculture, 196 Yasaka, Abashiri 099-2493, Japan.; Department of Bioscience, Okayama University of Science, 1-1 Ridaicho, Kita-ku, Okayama 700-0005, Japan.; School of Food Industrial Sciences, Miyagi University, 2-2-1 Hatatate, Taihaku-ku, Sendai 982-0215, Japan.
The red alga Neopyropia yezoensis undergoes polarized elongation and asymmetrical cell division of the apical stem cell during tip growth in filamentous generations of its life cycle: the conchocelis and conchosporangium. Side branches are also produced via tip growth, a process involving the regeneration and asymmetrical division of the apical stem cell. Here, we demonstrate that auxin plays a crucial role in these processes by using the auxin antagonist 2-(1H-Indol-3-yl)-4-oxo-4-phenyl-butyric acid (PEO-IAA), which specifically blocks the activity of the auxin receptor TRANSPORT INHIBITOR RESPONSE1 (TIR1) in land plants. PEO-IAA repressed both the regeneration and polarized tip growth of the apical stem cell in single-celled conchocelis; this phenomenon was reversed by treatment with the auxin indole-3-acetic acid (IAA). In addition, tip growth of the conchosporangium was accelerated by IAA treatment but repressed by PEO-IAA treatment. These findings indicate that auxin regulates polarized tip cell growth and that an auxin receptor-like protein is present in N. yezoensis. The sensitivity to different 5-alkoxy-IAA analogs differs considerably between N. yezoensis and Arabidopsis thaliana. N. yezoensis lacks a gene encoding TIR1, indicating that its auxin receptor-like protein differs from the auxin receptor of terrestrial plants. These findings shed light on auxin-induced mechanisms and the regulation of tip growth in plants.
PMID: 36078060
Cells , IF:6.6 , 2022 Aug , V11 (16) doi: 10.3390/cells11162484
Contrasting Roles of Ethylene Response Factors in Pathogen Response and Ripening in Fleshy Fruit.
Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China.; College of Agriculture and Biotechnology, Zhejiang University, Zijinggang Campus, Hangzhou 310058, China.; College of Food Science and Engineering, Hainan University, Haikou 570228, China.; Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijinggang Campus, Hangzhou 310058, China.; Plant and Crop Sciences Division, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK.
Fleshy fruits are generally hard and unpalatable when unripe; however, as they mature, their quality is transformed by the complex and dynamic genetic and biochemical process of ripening, which affects all cell compartments. Ripening fruits are enriched with nutrients such as acids, sugars, vitamins, attractive volatiles and pigments and develop a pleasant taste and texture and become attractive to eat. Ripening also increases sensitivity to pathogens, and this presents a crucial problem for fruit postharvest transport and storage: how to enhance pathogen resistance while maintaining ripening quality. Fruit development and ripening involve many changes in gene expression regulated by transcription factors (TFs), some of which respond to hormones such as auxin, abscisic acid (ABA) and ethylene. Ethylene response factor (ERF) TFs regulate both fruit ripening and resistance to pathogen stresses. Different ERFs regulate fruit ripening and/or pathogen responses in both fleshy climacteric and non-climacteric fruits and function cooperatively or independently of other TFs. In this review, we summarize the current status of studies on ERFs that regulate fruit ripening and responses to infection by several fungal pathogens, including a systematic ERF transcriptome analysis of fungal grey mould infection of tomato caused by Botrytis cinerea. This deepening understanding of the function of ERFs in fruit ripening and pathogen responses may identify novel approaches for engineering transcriptional regulation to improve fruit quality and pathogen resistance.
PMID: 36010560
Plant J , IF:6.417 , 2022 Sep doi: 10.1111/tpj.15987
A Germin-like protein OsGER4 is involved in promoting crown root development under exogenous Jasmonic acid treatment in rice.
University of Science and Technology of Hanoi, Vietnam Academy of Science and Technology. Hanoi, Vietnam.; School of Applied Mathematics and Informatics, University of Science and Technology of Hanoi. Hanoi, Vietnam.; Institute of Biotechnology, Vietnam Academy of Science and Technology. Hanoi, Vietnam.; Graduate University of Science and Technology, Vietnam Academy of Science and Technology, Hanoi, Vietnam.
In rice, crown roots (CR) are responsible for many important roles, such as root system expansion, water and mineral uptake, and adaptation to environmental stresses. Phytohormones such as auxin, cytokinin, and ethylene are known to control crown root initiation and development in rice. However, the role of Jasmonic acid (JA) in crown root development remained elusive. Here, we report that JA promotes CR development by regulating OsGER4, a rice Germin-like protein. Root phenotyping analysis revealed that exogenous JA treatment induced an increase in CR number in a concentration-dependent manner. A subsequent Genome-Wide Association Study (GWAS) and gene expression analyses pinpointed a strong association between Germin-Like Protein OsGER4 and the increase in CR number under exogenous JA treatment. ProGER4::GUS reporter line analysis showed that it is a hormone-responsive gene involved in various stress responses, mainly confined to epidermal and vascular tissues during crown root primordia development, and to vascular bundles of mature crown and lateral roots. Notable changes in OsGER4 expression patterns caused by polar auxin transport inhibitor NPA supports its connection to auxin signaling. Phenotyping experiments with OsGER4 knockout mutants confirmed that this gene is required for CR development under exogenous JA treatment. Overall, our results provide important insights into JA-mediated regulation of crown root development in rice.
PMID: 36134434
Plant J , IF:6.417 , 2022 Sep doi: 10.1111/tpj.15983
Multi-omics provides new insights into the domestication and improvement of dark jute (Corchorus olitorius).
Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, 410205, China.; Novogene Bioinformatics Institute, Beijing, 100015, China.; Department of Ecology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, 430072, China.; Natural Sciences and Science Education, National Institute of Education, Nanyang Technological University, 637616, Singapore.; Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117543, Singapore.
Jute (Corchorus sp.) is the most important bast fibre crop worldwide; however, the mechanisms underlying domestication and improvement remain large unknown. We performed multi-omics analysis by integrating de novo sequencing, resequencing, and transcriptomic and epigenetic sequencing, to clarify the domestication and improvement of dark jute C. olitorius. We demonstrated that dark jute underwent early domestication and a relatively moderate genetic bottleneck during improvement breeding. A genome-wide association study of 11 important agronomic traits identified abundant candidate loci. We characterized the selective sweeps in the two breeding stages of jute, prominently, soil salinity differences played an important role in environmental adaptation during domestication, and the strongly selected genes for improvement had an increased frequency of favorable haplotypes. Furthermore, we speculated that an encoding auxin/indole-3-acetic acid protein COS07g_00652 could enhance the flexibility and strength of the stem to improve fibre yield. Our study not only provides valuable genetic resources for future fiber breeding in jute but also is of great significance for reviewing the genetic basis of early crop breeding.
PMID: 36129373
Plant J , IF:6.417 , 2022 Sep doi: 10.1111/tpj.15979
N-terminal domain of ARF-GEF GNOM prevents heterodimerisation with functionally divergent GNL1 in Arabidopsis.
Center for Plant Molecular Biology (ZMBP), Developmental Genetics, University of Tubingen, Auf der Morgenstelle 32, 72076, Tubingen, Germany.; Sainsbury Laboratory, University of Cambridge, 47 Bateman Street, Cambridge, CB2 1LR, UK.; Cellular Morphogenesis Group, University of Erlangen, Staudtstr. 5, 91058, Erlangen, Germany.; Laboratory of Plant Growth and Development, Department of Biology, Graduate School of Science and Faculty of Science, Osaka University, Toyonaka, Osaka, 560-0043, Japan.
Evolutionary change following gene duplication can lead to functionally divergent paralogous proteins. If comprising identical subunits their random assortment would also form potentially detrimental heteromeric proteins. In Arabidopsis, ARF GTPase guanine-nucleotide exchange factor (ARF-GEF) GNOM is essential for polar recycling of auxin-efflux transporter PIN1 from endosomes to the basal plasma membrane whereas its paralog GNL1 mediates retrograde Golgi-ER traffic. Here we show that both GNOM and GNL1 form homodimers but no heterodimers. To assess the biological significance of this, we generated transgenic plants expressing engineered heterodimer-compatible GNOM variants. Those plants showed developmental defects such as the failure to produce lateral roots. To identify mechanisms underlying heterodimer prevention, we analyzed interactions of the N-terminal dimerization and cyclophilin binding (DCB) domain. Each DCB domain interacted with the complementary fragment (DeltaDCB) of both their own and the paralogous protein. However, only DCB(GNOM) interacted with itself whereas DCB(GNL1) failed to interact with itself and with DCB(GNOM) . GNOM variants in which the DCB domain was removed or replaced by DCB(GNL1) revealed a role for DCB-DCB interaction in the prevention of GNOM-GNL1 heterodimers whereas DCB-DeltaDCB interaction was essential for dimer formation and GNOM function. Our data suggest a model of early DCB-DCB interaction that facilitates GNOM homodimer formation, indirectly precluding formation of detrimental heterodimers.
PMID: 36106415
Plant J , IF:6.417 , 2022 Aug doi: 10.1111/tpj.15960
Bioenergy sorghum stem growth regulation: intercalary meristem localization, development, and gene regulatory network analysis.
Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, 77843-2128, USA.; ABQMR, Inc., 2301 Yale Blvd. SE, Suite C2, Albuquerque, New Mexico, 87106, USA.; Department of Plant Biology, University of Illinois, Champaign-Urbana, Illinois, 61801, USA.
Bioenergy sorghum is a highly productive drought tolerant C4 grass that accumulates 80% of its harvestable biomass in approximately 4 m length stems. Stem internode growth is regulated by development, shading, and hormones that modulate cell proliferation in intercalary meristems (IMs). In this study, sorghum stem IMs were localized above the pulvinus at the base of elongating internodes using magnetic resonance imaging, microscopy, and transcriptome analysis. A change in cell morphology/organization occurred at the junction between the pulvinus and internode where LATERAL ORGAN BOUNDARIES (SbLOB), a boundary layer gene, was expressed. Inactivation of an AGCVIII kinase in DDYM (dw2) resulted in decreased SbLOB expression, disrupted IM localization, and reduced internode cell proliferation. Transcriptome analysis identified approximately 1000 genes involved in cell proliferation, hormone signaling, and other functions selectively upregulated in the IM compared with a non-meristematic stem tissue. This cohort of genes is expressed in apical dome stem tissues before localization of the IM at the base of elongating internodes. Gene regulatory network analysis identified connections between genes involved in hormone signaling and cell proliferation. The results indicate that gibberellic acid induces accumulation of growth regulatory factors (GRFs) known to interact with ANGUSTIFOLIA (SbAN3), a master regulator of cell proliferation. GRF:AN3 was predicted to induce SbARF3/ETT expression and regulate SbAN3 expression in an auxin-dependent manner. GRFs and ARFs regulate genes involved in cytokinin and brassinosteroid signaling and cell proliferation. The results provide a molecular framework for understanding how hormone signaling regulates the expression of genes involved in cell proliferation in the stem IM.
PMID: 36038985
Antioxidants (Basel) , IF:6.312 , 2022 Sep , V11 (9) doi: 10.3390/antiox11091792
Exogenous Betaine Enhances the Protrusion Vigor of Rice Seeds under Heat Stress by Regulating Plant Hormone Signal Transduction and Its Interaction Network.
Department of Agronomy, College of Agronomy, Hunan Agricultural University, Changsha 410128, China.; The Key Laboratory of Crop Germplasm Innovation and Resource Utilization of Hunan Province, Hunan Agricultural University, Changsha 410128, China.
Rice is an important food crop. Rice seedlings are mainly composed of root, coleoptile, mesocotyl and euphylla. The elongation of coleoptile and mesocotyl promotes the emergence of rice seedlings. Therefore, analyzing the mechanism of coleoptile and mesocotyl elongation is important for the cultivation of rice varieties. Due to global warming, heat stress is threatening rice yields. Betaine plays an important role in plant resistance to heat stress; however, we lack research on its regulation mechanism of rice seed germination under heat stress. Therefore, we explored the effects of soaking seeds with betaine at different concentrations on rice seed germination under heat stress. According to the results, soaking seeds with 10 mM of betaine could effectively improve the seeds' germination potential and rate under heat stress to promote the germination of rice seeds. To clarify the mitigation mechanism of betaine in heat stress, we measured the antioxidant enzyme activity, malondialdehyde content, soluble protein content and endogenous hormone content of seed protrusion under heat stress. We constructed the cDNA library for transcriptome sequencing. According to the results, 10 mM of betaine improved the activities of the superoxide dismutase, peroxidase and catalase of seed protrusion under heat stress to reduce the malondialdehyde content and increase the soluble protein content to alleviate the effect of heat stress on rice seed germination. The detection of the endogenous hormone content showed that soaking seeds with 10 mM of betaine increased the content of gibberellin and decreased the contents of auxin and abscisic acid of seed protrusion under heat stress. According to the transcriptome analysis, betaine can induce the expressions of key genes in the biosynthesis and metabolism of auxin, abscisic acid and gibberellins in the seed coleoptile and mesocotyl elongation stage, regulate the signal transduction of three hormones and promote the germination of rice seeds under heat stress. This study revealed, for the first time, the physiological and molecular regulation mechanism of betaine promotion of seed germination under heat stress.
PMID: 36139866
Int J Mol Sci , IF:5.923 , 2022 Sep , V23 (18) doi: 10.3390/ijms231810923
Genome-Wide Identification, Evolution, and Expression Analysis of GASA Gene Family in Prunus mume.
Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, Engineering Research Center of Landscape Environment of Ministry of Education, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, School of Landscape Architecture, Beijing Forestry University, Beijing 100083, China.
The Gibberellic Acid Stimulated Arabidopsis/Gibberellin Stimulated Transcript (GASA/GAST) gene family is a group of plant-specific genes encoding cysteine-rich peptides essential to plant growth, development, and stress responses. Although GASA family genes have been identified in various plant species, their functional roles in Prunus mume are still unknown. In this study, a total of 16 PmGASA genes were identified via a genome-wide scan in Prunus mume and were grouped into three major gene clades based on the phylogenetic tree. All PmGASA proteins possessed the conserved GASA domain, consisting of 12-cysteine residues, but varied slightly in protein physiochemical properties and motif composition. With evolutionary analysis, we observed that duplications and purifying selection are major forces driving PmGASA family gene evolution. By analyzing PmGASA promoters, we detected a number of hormonal-response related cis-elements and constructed a putative transcriptional regulatory network for PmGASAs. To further understand the functional role of PmGASA genes, we analyzed the expression patterns of PmGASAs across different organs and during various biological processes. The expression analysis revealed the functional implication of PmGASA gene members in gibberellic acid-, abscisic acid-, and auxin-signaling, and during the progression of floral bud break in P. mume. To summarize, these findings provide a comprehensive understanding of GASA family genes in P. mume and offer a theoretical basis for future research on the functional characterization of GASA genes in other woody perennials.
PMID: 36142832
Int J Mol Sci , IF:5.923 , 2022 Sep , V23 (18) doi: 10.3390/ijms231810642
The Plastidial DIG5 Protein Affects Lateral Root Development by Regulating Flavonoid Biosynthesis and Auxin Transport in Arabidopsis.
Donald Danforth Plant Science Center, St. Louis, MO 63132, USA.; High-Tech Research Center, Shandong Academy of Agricultural Sciences, Jinan 250100, China.; College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China.; Department of Biology, Hong Kong Baptist University, Kowloon Tang, Hong Kong, China.; Department of Plant Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-713, Korea.; Inner Mongolia Key Laboratory of Plant Stress Physiology and Molecular Biology, Inner Mongolia Agricultural University, Hohhot 010010, China.; State Key Laboratory for Agribiotechnology, Chinese University of Hong Kong, Hong Kong, China.
To reveal the mechanisms underlying root adaptation to drought stress, we isolated and characterized an Arabidopsis mutant, dig5 (drought inhibition of lateral root growth 5), which exhibited increased sensitivity to the phytohormone abscisic acid (ABA) for the inhibition of lateral root growth. The dig5 mutant also had fewer lateral roots under normal conditions and the aerial parts were yellowish with a lower level of chlorophylls. The mutant seedlings also displayed phenotypes indicative of impaired auxin transport, such as abnormal root curling, leaf venation defects, absence of apical hook formation, and reduced hypocotyl elongation in darkness. Auxin transport assays with [(3)H]-labeled indole acetic acid (IAA) confirmed that dig5 roots were impaired in polar auxin transport. Map-based cloning and complementation assays indicated that the DIG5 locus encodes a chloroplast-localized tRNA adenosine deaminase arginine (TADA) that is involved in chloroplast protein translation. The levels of flavonoids, which are naturally occurring auxin transport inhibitors in plants, were significantly higher in dig5 roots than in the wild type roots. Further investigation showed that flavonoid biosynthetic genes were upregulated in dig5. Introduction of the flavonoid biosynthetic mutation transparent testa 4 (tt4) into dig5 restored the lateral root growth of dig5. Our study uncovers an important role of DIG5/TADA in retrogradely controlling flavonoid biosynthesis and lateral root development. We suggest that the DIG5-related signaling pathways, triggered likely by drought-induced chlorophyll breakdown and leaf senescence, may potentially help the plants to adapt to drought stress through optimizing the root system architecture.
PMID: 36142550
Int J Mol Sci , IF:5.923 , 2022 Sep , V23 (18) doi: 10.3390/ijms231810596
Integrated Analysis of Transcriptome and Small RNAome Reveals the Regulatory Network for Rapid Growth in Mikania micrantha.
Guangdong Provincial Key Laboratory for Plant Epigenetics, Longhua Bioindustry and Innovation Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China.
M. micrantha has caused huge ecological damage and economic losses worldwide due to its rapid growth and serious invasion. However, the underlying molecular mechanisms of its rapid growth and environmental adaption remain unclear. Here, we performed transcriptome and small RNA sequencing with five tissues of M. micrantha to dissect miRNA-mediated regulation in M. micrantha. WGCNA and GO enrichment analysis of transcriptome identified the gene association patterns and potential key regulatory genes for plant growth in each tissue. The genes highly correlated with leaf and stem tissues were mainly involved in the chlorophyll synthesis, response to auxin, the CAM pathway and other photosynthesis-related processes, which promoted the fast growth of M. micrantha. Importantly, we identified 350 conserved and 192 novel miRNAs, many of which displayed differential expression patterns among tissues. PsRNA target prediction analysis uncovered target genes of both conserved and novel miRNAs, including GRFs and TCPs, which were essential for plant growth and development. Further analysis revealed that miRNAs contributed to the regulation of tissue-specific gene expression in M. micrantha, such as mmi-miR396 and mmi-miR319. Taken together, our study uncovered the miRNA-mRNA regulatory networks and the potential vital roles of miRNAs in modulating the rapid growth of M. micrantha.
PMID: 36142547
Int J Mol Sci , IF:5.923 , 2022 Sep , V23 (18) doi: 10.3390/ijms231810548
Plants in Microgravity: Molecular and Technological Perspectives.
Umea Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83 Umea, Sweden.; Doctoral School of Neuroscience, Semmelweis University, H-1083 Budapest, Hungary.; Theoretical Neuroscience and Complex Systems Group, Department of Computational Sciences, Wigner Research Centre for Physics, H-1121 Budapest, Hungary.; Department of Plant Biology, Faculty of Science and Informatics, University of Szeged, Kozep fasor 52, H-6726 Szeged, Hungary.; Biological Research Centre (BRC), Institute of Plant Biology, Eotvos Lorand Research Network (ELKH), H-6726 Szeged, Hungary.
Plants are vital components of our ecosystem for a balanced life here on Earth, as a source of both food and oxygen for survival. Recent space exploration has extended the field of plant biology, allowing for future studies on life support farming on distant planets. This exploration will utilize life support technologies for long-term human space flights and settlements. Such longer space missions will depend on the supply of clean air, food, and proper waste management. The ubiquitous force of gravity is known to impact plant growth and development. Despite this, we still have limited knowledge about how plants can sense and adapt to microgravity in space. Thus, the ability of plants to survive in microgravity in space settings becomes an intriguing topic to be investigated in detail. The new knowledge could be applied to provide food for astronaut missions to space and could also teach us more about how plants can adapt to unique environments. Here, we briefly review and discuss the current knowledge about plant gravity-sensing mechanisms and the experimental possibilities to research microgravity-effects on plants either on the Earth or in orbit.
PMID: 36142459
Int J Mol Sci , IF:5.923 , 2022 Sep , V23 (18) doi: 10.3390/ijms231810527
Ustilaginoidea virens Nuclear Effector SCRE4 Suppresses Rice Immunity via Inhibiting Expression of a Positive Immune Regulator OsARF17.
Department of Plant Pathology, The Ministry of Agriculture Key Laboratory of Pest Monitoring and Green Management, and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, China Agricultural University, Beijing 100193, China.; Rice Research Institute, Sichuan Agricultural University, Chengdu 611130, China.; State Key Laboratory for Quality and Safety of Agro-Products, Key Laboratory of Biotechnology in Plant Protection of Ministry of Agriculture of China and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo 315211, China.; College of Plant Protection, Jilin Agricultural University, Changchun 130118, China.
Rice false smut caused by the biotrophic fungal pathogen Ustilaginoidea virens has become one of the most important diseases in rice. The large effector repertory in U. virens plays a crucial role in virulence. However, current knowledge of molecular mechanisms how U. virens effectors target rice immune signaling to promote infection is very limited. In this study, we identified and characterized an essential virulence effector, SCRE4 (Secreted Cysteine-Rich Effector 4), in U. virens. SCRE4 was confirmed as a secreted nuclear effector through yeast secretion, translocation assays and protein subcellular localization, as well as up-regulation during infection. The SCRE4 gene deletion attenuated the virulence of U. virens to rice. Consistently, ectopic expression of SCRE4 in rice inhibited chitin-triggered immunity and enhanced susceptibility to false smut, substantiating that SCRE4 is an essential virulence factor. Furthermore, SCRE4 transcriptionally suppressed the expression of OsARF17, an auxin response factor in rice, which positively regulates rice immune responses and resistance against U. virens. Additionally, the immunosuppressive capacity of SCRE4 depended on its nuclear localization. Therefore, we uncovered a virulence strategy in U. virens that transcriptionally suppresses the expression of the immune positive modulator OsARF17 through nucleus-localized effector SCRE4 to facilitate infection.
PMID: 36142440
Int J Mol Sci , IF:5.923 , 2022 Sep , V23 (18) doi: 10.3390/ijms231810360
Proteomic and Biochemical Approaches Elucidate the Role of Millimeter-Wave Irradiation in Wheat Growth under Flooding Stress.
Faculty of Environment and Information Sciences, Fukui University of Technology, Fukui 910-8505, Japan.; Research Center for Development of Far-Infrared Region, University of Fukui, Fukui 910-8507, Japan.; Department of Medical Technology, Yokkaichi Nursing and Medical Care University, Yokkaichi 512-8045, Japan.; Institute for Comprehensive Medical Science, Fujita Health University, Toyoake 470-1192, Japan.
Flooding impairs wheat growth and considerably affects yield productivity worldwide. On the other hand, irradiation with millimeter waves enhanced the growth of chickpea and soybean under flooding stress. In the current work, millimeter-wave irradiation notably enhanced wheat growth, even under flooding stress. To explore the protective mechanisms of millimeter-wave irradiation on wheat under flooding, quantitative proteomics was performed. According to functional categorization, proteins whose abundances were changed significantly with and without irradiation under flooding stress were correlated to glycolysis, reactive-oxygen species scavenging, cell organization, and hormonal metabolism. Immunoblot analysis confirmed that fructose-bisphosphate aldolase and beta tubulin accumulated in root and leaf under flooding; however, even in such condition, their accumulations were recovered to the control level in irradiated wheat. The abundance of ascorbate peroxidase increased in leaf under flooding and recovered to the control level in irradiated wheat. Because the abundance of auxin-related proteins changed with millimeter-wave irradiation, auxin was applied to wheat under flooding, resulting in the application of auxin improving its growth, even in such condition. These results suggest that millimeter-wave irradiation on wheat seeds improves the recovery of plant growth from flooding via the regulation of glycolysis, reactive-oxygen species scavenging, and cell organization. Additionally, millimeter-wave irradiation could promote tolerance against flooding through the regulation of auxin contents in wheat.
PMID: 36142271
Int J Mol Sci , IF:5.923 , 2022 Sep , V23 (17) doi: 10.3390/ijms231710183
Genome-Wide Characterization of PIN Auxin Efflux Carrier Gene Family in Mikania micrantha.
Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, College of Life Sciences, South China Normal University, Guangzhou 510631, China.; Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
Mikania micrantha, recognized as one of the world's top 10 pernicious weeds, is a rapidly spreading tropical vine that has invaded the coastal areas of South China, causing serious economic losses and environmental damage. Rapid stem growth is an important feature of M. micrantha which may be related to its greater number of genes involved in auxin signaling and transport pathways and its ability to synthesize more auxin under adverse conditions to promote or maintain stem growth. Plant growth and development is closely connected to the regulation of endogenous hormones, especially the polar transport and asymmetric distribution of auxin. The PIN-FORMED (PIN) auxin efflux carrier gene family plays a key role in the polar transport of auxin and then regulates the growth of different plant tissues, which could indicate that the rapid growth of M. micrantha is closely related to this PIN-dependent auxin regulation. In this study, 11 PIN genes were identified and the phylogenetic relationship and structural compositions of the gene family in M. micrantha were analyzed by employing multiple bioinformatic methods. The phylogenetic analysis indicated that the PIN proteins could be divided into five distinct clades. The structural analysis revealed that three putative types of PIN (canonical, noncanonical and semi-canonical) exist among the proteins according to the length and the composition of the hydrophilic domain. The majority of the PINs were involved in the process of axillary bud differentiation and stem response under abiotic stress, indicating that M. micrantha may regulate its growth, development and stress response by regulating PIN expression in the axillary bud and stem, which may help explain its strong growth ability and environmental adaptability. Our study emphasized the structural features and stress response patterns of the PIN gene family and provided useful insights for further study into the molecular mechanism of auxin-regulated growth and control in M. micrantha.
PMID: 36077586
Int J Mol Sci , IF:5.923 , 2022 Sep , V23 (17) doi: 10.3390/ijms23179976
Cane Vinasses Contain Bioactive Concentrations of Auxin and Abscisic Acid in Their Composition.
Department of Environmental Biology, Faculty of Sciences, BIOMA Institute, University of Navarra, 31008 Pamplona, Spain.; Department of Marketing, Timac Agro, Porto Alegre 90480-001, Brazil.
Currently, high doses of vinasse are employed for the fertigation of sugarcane with positive results on yield. Usually, this effect is related to the presence of mineral nutrients in its composition as well as to its action on soil properties. Consequently, the concentrations of minerals, organic acids, and other metabolites in vinasse are very well characterized. However, considering that cane vinasses are obtained from the treatment of vegetal tissues, it is also possible that they might contain significant concentrations of phytoregulators that could have a relevant role in their beneficial action on yield. To investigate this hypothesis, we analyzed the main plant hormones in 22 samples of vinasse collected in different production sites of Brazil using HPLC-mass spectrometry. The results show that both ABA and IAA present concentrations in vinasse within the micromolar range, thus being potential active ingredients affecting plant development. In conclusion, the beneficial action of cane vinasses on sugarcane yield might involve, among other factors, the action of IAA and ABA on plant growth.
PMID: 36077383
Int J Mol Sci , IF:5.923 , 2022 Sep , V23 (17) doi: 10.3390/ijms23179942
GhBOP1 as a Key Factor of Ribosomal Biogenesis: Development of Wrinkled Leaves in Upland Cotton.
State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang 455099, China.; College of Life Sciences, Shaanxi Normal University, Xi'an 710062, China.; Hainan Yazhou Bay Seed Lab, Sanya 572000, China.; National Nanfan Research Institute (Sanya), Chinese Academy of Agricultural Sciences, Sanya 572000, China.
Block of proliferation 1 (BOP1) is a key protein that helps in the maturation of ribosomes and promotes the progression of the cell cycle. However, its role in the leaf morphogenesis of cotton remains unknown. Herein, we report and study the function of GhBOP1 isolated from Gossypium hirsutum. The sequence alignment revealed that BOP1 protein was highly conserved among different species. The yeast two-hybrid experiments, bimolecular fluorescence complementation, and luciferase complementation techniques revealed that GhBOP1 interact with GhPES and GhWDR12. Subcellular localization experiments revealed that GhBOP1, GhPES and GhWDR12 were localized at the nucleolus. Suppression of GhBOP1 transcripts resulted in the uneven bending of leaf margins and the presence of young wrinkled leaves by virus-induced gene silencing assay. Abnormal palisade arrangements and the presence of large upper epidermal cells were observed in the paraffin sections of the wrinkled leaves. Meanwhile, a jasmonic acid-related gene, GhOPR3, expression was increased. In addition, a negative effect was exerted on the cell cycle and the downregulation of the auxin-related genes was also observed. These results suggest that GhBOP1 plays a critical role in the development of wrinkled cotton leaves, and the process is potentially modulated through phytohormone signaling.
PMID: 36077339
Int J Mol Sci , IF:5.923 , 2022 Aug , V23 (17) doi: 10.3390/ijms23179556
Comparative Transcriptomic and Metabolic Analyses Reveal the Coordinated Mechanisms in Pinus koraiensis under Different Light Stress Conditions.
State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China.; Jilin Provincial Key Laboratory of Tree and Grass Genetics and Breeding, College of Forestry and Grassland Science, Jilin Agricultural University, Changchun 130118, China.; Jilin Province Forestry Survey Design & Research Institute, Changchun 130022, China.
Light is one of the most important environmental cues that affects plant development and regulates its behavior. Light stress directly inhibits physiological responses and plant tissue development and even induces mortality in plants. Korean pine (Pinus koraiensis) is an evergreen conifer species widely planted in northeast China that has important economic and ecological value. However, the effects of light stress on the growth and development of Korean pine are still unclear. In this study, the effects of different shading conditions on physiological indices, molecular mechanisms and metabolites of Korean pine were explored. The results showed that auxin, gibberellin and abscisic acid were significantly increased under all shading conditions compared with the control. The contents of chlorophyll a, chlorophyll b, total chlorophyll and carotenoid also increased as the shading degree increased. Moreover, a total of 8556, 3751 and 6990 differentially expressed genes (DEGs) were found between the control and HS (heavy shade), control and LS (light shade), LS vs. HS, respectively. Notably, most DEGs were assigned to pathways of phytohormone signaling, photosynthesis, carotenoid and flavonoid biosynthesis under light stress. The transcription factors MYB-related, AP2-ERF and bHLH specifically increased expression during light stress. A total of 911 metabolites were identified, and 243 differentially accumulated metabolites (DAMs) were detected, among which flavonoid biosynthesis (naringenin chalcone, dihydrokaempferol and kaempferol) metabolites were significantly different under light stress. These results will provide a theoretical basis for the response of P. koraiensis to different light stresses.
PMID: 36076949
Int J Mol Sci , IF:5.923 , 2022 Aug , V23 (16) doi: 10.3390/ijms23169477
The miR393-Target Module Regulates Plant Development and Responses to Biotic and Abiotic Stresses.
Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou 225009, China.; School of Biological Sciences, University of Western Australia, Perth, WA 6009, Australia.; Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou 225009, China.
MicroRNAs (miRNAs), a class of endogenous small RNAs, are broadly involved in plant development, morphogenesis and responses to various environmental stresses, through manipulating the cleavage, translational expression, or DNA methylation of target mRNAs. miR393 is a conserved miRNA family present in many plants, which mainly targets genes encoding the transport inhibitor response1 (TIR1)/auxin signaling F-box (AFB) auxin receptors, and thus greatly affects the auxin signal perception, Aux/IAA degradation, and related gene expression. This review introduces the advances made on the miR393/target module regulating plant development and the plant's responses to biotic and abiotic stresses. This module is valuable for genetic manipulation of optimized conditions for crop growth and development and would also be helpful in improving crop yield through molecular breeding.
PMID: 36012740
Int J Mol Sci , IF:5.923 , 2022 Aug , V23 (16) doi: 10.3390/ijms23169472
A Long Noncoding RNA Derived from lncRNA-mRNA Networks Modulates Seed Vigor.
National Engineering Research Center of Plant Space Breeding, South China Agricultural University, Guangzhou 510642, China.
The discovery of long noncoding RNAs (lncRNAs) has filled a great gap in our understanding of posttranscriptional gene regulation in a variety of biological processes related to plant stress responses. However, systematic analyses of the lncRNAs expressed in rice seeds that germinate under cold stress have been elusive. In this study, we performed strand-specific whole transcriptome sequencing in germinated rice seeds under cold stress and normal temperature. A total of 6258 putative lncRNAs were identified and expressed in a stage-specific manner compared to mRNA. By investigating the targets of differentially expressed (DE) lncRNAs of LT-I (phase I of low temperature)/NT-I (phase I of normal temperature), it was shown that the auxin-activated signaling pathway was significantly enriched, and twenty-three protein-coding genes with most of the members of the SAUR family located in chromosome 9 were identified as the candidate target genes that may interact with five lncRNAs. A seed vigor-related lncRNA, SVR, which interplays with the members of the SAUR gene family in cis was eventually identified. The CRISPR/Cas 9 engineered mutations in SVR cause delay of germination. The findings provided new insights into the connection between lncRNAs and the auxin-activated signaling pathway in the regulation of rice seed vigor.
PMID: 36012737
Int J Mol Sci , IF:5.923 , 2022 Aug , V23 (16) doi: 10.3390/ijms23169456
Effects of Exogenous Melatonin on Root Physiology, Transcriptome and Metabolome of Cotton Seedlings under Salt Stress.
State Key Laboratory of North China Crop Improvement and Regulation, College of Life Science, Hebei Agricultural University, Baoding 071000, China.; State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Crop Growth Regulation of Hebei Province, College of Agronomy, Hebei Agricultural University, Baoding 071000, China.; College of Landscape and Tourism, Hebei Agricultural University, Baoding 071000, China.; Cotton Research Center, Key Laboratory of Cotton Breeding and Cultivation in Huang-Huai-Hai Plain, Ministry of Agriculture, Shandong Academy of Agricultural Sciences, Jinan 250100, China.
Root systems are the key organs through which plants absorb water and nutrients and perceive the soil environment and thus are easily damaged by salt stress. Melatonin can alleviate stress-induced damage to roots. The present study investigated the effects of exogenous melatonin on the root physiology, transcriptome and metabolome of cotton seedlings under salt stress. Salt stress was observed to damage the cell structure and disorder the physiological system of cotton seedling roots. After subjecting melatonin-soaked seeds to salt stress, the activities of SOD, CAT and POD in cotton seedling roots increased by 10-25%, 50-60% and 50-60%, respectively. The accumulation of H2O2 and MDA were significantly decreased by 30-60% and 30-50%, respectively. The contents of soluble sugar, soluble protein and K(+) increased by 15-30%, 15-30% and 20-50%, respectively, while the Na(+) content was significantly reduced. Melatonin also increased auxin (by 20-40%), brassinosteroids (by 5-40%) and gibberellin (by 5-35%) and promoted melatonin content and root activity. Exogenous melatonin maintained the integrity of root cells and increased the number of organelles. Transcriptomic and metabolomic results showed that exogenous melatonin could mitigate the salt-stress-induced inhibition of plant root development by regulating the reactive oxygen species scavenging system; ABC transporter synthesis; plant hormone signal transduction, endogenous melatonin gene expression; and the expression of the transcription factors MYB, TGA and WRKY33. These results provide a new direction and empirical basis for improving crop salt tolerance with melatonin.
PMID: 36012720
Int J Mol Sci , IF:5.923 , 2022 Aug , V23 (16) doi: 10.3390/ijms23169454
The MdAux/IAA2 Transcription Repressor Regulates Cell and Fruit Size in Apple Fruit.
Mudanjiang Branch, Heilongjiang Academy of Agricultural Sciences, Mudanjiang 157000, China.; Key Laboratory of Fruit Postharvest Biology (Liaoning Province), Key Laboratory of Protected Horticulture (Ministry of Education), National & Local Joint Engineering Research Center of Northern Horticultural Facilities Design & Application Technology (Liaoning), College of Horticulture, Shenyang Agricultural University, Shenyang 110866, China.
Auxin plays an important role in regulating plant development, and Auxin/indole acetic acid (Aux/IAA) is a type of auxin-responsive gene and plays an important role in auxin signaling; to date, although 29 Aux/IAA proteins have been reported in Abrabidopsis thaliana, only parts of the Aux/IAA family gene functions have been identified. We previously reported that a bud sport of 'Longfeng' (LF) apple (Malus domestica), named 'Grand longfeng' (GLF), which showed a larger fruit size than LF, has lower expression of MdAux/IAA2. In this study, we identified the function of the MdAux/IAA2 gene in apple fruit size difference using Agrobacterium-mediated genetic transformation. Overexpression of MdAux/IAA2 decreased the apple flesh callus increment and caused a smaller globular cell size. In addition, overexpression of MdAux/IAA2 in GLF fruit resulted in the reduction of apple fruit size, weight, and cell size, while silencing MdAux/IAA2 in LF apple fruit resulted in an increase in apple fruit weight and cell size. We suggest that the high auxin content depressed the expression of MdAux/IAA2, and that the downregulated expression of MdAux/IAA2 led to the formation of GLF. Our study suggests a mechanism for fruit size regulation in plants and we will explore the transcription factors functioning in this process in the future.
PMID: 36012719
Int J Mol Sci , IF:5.923 , 2022 Aug , V23 (16) doi: 10.3390/ijms23169379
Salicylic Acid Regulates Root Gravitropic Growth via Clathrin-Independent Endocytic Trafficking of PIN2 Auxin Transporter in Arabidopsis thaliana.
The Engineering Research Institute of Agriculture and Forestry, Ludong University, Yantai 264025, China.; College of Life Sciences, Nanjing University, Nanjing 210093, China.; CAS Center for Excellence in Molecular Plant Sciences, Shanghai 201602, China.
The phytohormone salicylic acid (SA) plays a crucial role in plant growth and development. However, the mechanism of high-concentration SA-affected gravitropic response in plant root growth and root hair development is still largely unclear. In this study, wild-type, pin2 mutant and various transgenic fluorescence marker lines of Arabidopsis thaliana were investigated to understand how root growth is affected by high SA treatment under gravitropic stress conditions. We found that exogenous SA application inhibited gravitropic root growth and root hair development in a dose-dependent manner. Further analyses using DIRECT REPEAT5 (DR5)-GFP, auxin sensor DII-VENUS, auxin efflux transporter PIN2-GFP, trans-Golgi network/early endosome (TGN/EE) clathrin-light-chain 2 (CLC2)-mCherry and prevacuolar compartment (PVC) (Rha1)-mCherry transgenic marker lines demonstrated that high SA treatment severely affected auxin accumulation, root-specific PIN2 distribution and PIN2 gene transcription and promoted the vacuolar degradation of PIN2, possibly independent of clathrin-mediated endocytic protein trafficking. Our findings proposed a new underlying mechanism of SA-affected gravitropic root growth and root hair development via the regulation of PIN2 gene transcription and PIN2 protein endocytosis in plants.
PMID: 36012641
Int J Mol Sci , IF:5.923 , 2022 Aug , V23 (16) doi: 10.3390/ijms23169270
Regulation of Heat Stress in Physcomitrium (Physcomitrella) patens Provides Novel Insight into the Functions of Plant RNase H1s.
State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan 430062, China.; School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, China.; Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Key Laboratory of Plant Functional Genomics of the Ministry of Education, College of Agriculture, Yangzhou University, Yangzhou 225009, China.; Co-Innovation Center for Modern Production Technology of Grain Crops of Jiangsu Province/Key Laboratory of Crop Genetics and Physiology of Jiangsu Province, Yangzhou University, Yangzhou 225009, China.
RNase H1s are associated with growth and development in both plants and animals, while the roles of RNase H1s in bryophytes have been rarely reported. Our previous data found that PpRNH1A, a member of the RNase H1 family, could regulate the development of Physcomitrium (Physcomitrella) patens by regulating the auxin. In this study, we further investigated the biological functions of PpRNH1A and found PpRNH1A may participate in response to heat stress by affecting the numbers and the mobilization of lipid droplets and regulating the expression of heat-related genes. The expression level of PpRNH1A was induced by heat stress (HS), and we found that the PpRNH1A overexpression plants (A-OE) were more sensitive to HS. At the same time, A-OE plants have a higher number of lipid droplets but with less mobility in cells. Consistent with the HS sensitivity phenotype in A-OE plants, transcriptomic analysis results indicated that PpRNH1A is involved in the regulation of expression of heat-related genes such as DNAJ and DNAJC. Taken together, these results provide novel insight into the functions of RNase H1s.
PMID: 36012542
Int J Mol Sci , IF:5.923 , 2022 Aug , V23 (16) doi: 10.3390/ijms23169043
Genome-Wide Identification and Analysis of the Growth-Regulating Factor Family in Zanthoxylum armatum DC and Functional Analysis of ZaGRF6 in Leaf Size and Longevity Regulation.
Key Laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), College of Life Sciences/Institute of Agro-Bioengineering, Guizhou University, Guiyang 550025, China.
Growth-regulating factors (GRFs) are plant-specific transcription factors that play an important role in plant growth and development. In this study, fifteen GRF gene members containing QLQ and WRC domains were identified in Zanthoxylum armatum. Phylogenetic and collinearity analysis showed that ZaGRFs were closely related to CsGRFs and AtGRFs, and distantly related to OsGRFs. There are a large number of cis-acting elements related to hormone response and stress induction in the GRF gene promoter region of Z. armatum. Tissue-specific expression analysis showed that except for ZaGRF7, all the ZaGRFs were highly expressed in young parts with active growth and development, including terminal buds, seeds, and young flowers, suggesting their key roles in Z. armatum growth and development. Eight ZaGRFs were selected to investigate the transcriptional response to auxin, gibberellin and drought treatments. A total of six ZaGRFs in the NAA treatment, four ZaGRFs in the GA3 treatment, and six ZaGRFs in the PEG treatment were induced and significantly up-regulated. Overexpression of ZaGRF6 increased branching and chlorophyll content and delayed senescence of transgenic Nicotiana benthamiana. ZaGRF6 increased the expression of CRF2 and suppressed the expression of ARR4 and CKX1, indicating that ZaGRF6 is involved in cytokinin metabolism and signal transduction. These research results lay a foundation for further analysis of the GRF gene function of Z. armatum and provide candidate genes for growth, development, and stress resistance breeding of Z. armatum.
PMID: 36012309
Int J Mol Sci , IF:5.923 , 2022 Aug , V23 (16) doi: 10.3390/ijms23168965
Mutation of OsPIN1b by CRISPR/Cas9 Reveals a Role for Auxin Transport in Modulating Rice Architecture and Root Gravitropism.
College of Agriculture, Henan University of Science and Technology, Luoyang 471000, China.
The distribution and content of auxin within plant tissues affect a variety of important growth and developmental processes. Polar auxin transport (PAT), mainly mediated by auxin influx and efflux transporters, plays a vital role in determining auxin maxima and gradients in plants. The auxin efflux carrier PIN-FORMED (PIN) family is one of the major protein families involved in PAT. Rice (Oryza sativa L.) genome possesses 12 OsPIN genes. However, the detailed functions of OsPIN genes involved in regulating the rice architecture and gravity response are less well understood. In the present study, OsPIN1b was disrupted by CRISPR/Cas9 technology, and its roles in modulating rice architecture and root gravitropism were investigated. Tissue-specific analysis showed that OsPIN1b was mainly expressed in roots, stems and sheaths at the seedling stage, and the transcript abundance was progressively decreased during the seedling stages. Expression of OsPIN1b could be quickly and greatly induced by NAA, indicating that OsPIN1b played a vital role in PAT. IAA homeostasis was disturbed in ospin1b mutants, as evidenced by the changed sensitivity of shoot and root to NAA and NPA treatment, respectively. Mutation of OsPIN1b resulted in pleiotropic phenotypes, including decreased growth of shoots and primary roots, reduced adventitious root number in rice seedlings, as well as shorter and narrower leaves, increased leaf angle, more tiller number and decreased plant height and panicle length at the late developmental stage. Moreover, ospin1b mutants displayed a curly root phenotype cultured with tap water regardless of lighting conditions, while nutrient solution culture could partially rescue the curly root phenotype in light and almost completely abolish this phenotype in darkness, indicating the involvement of the integration of light and nutrient signals in root gravitropism regulation. Additionally, amyloplast sedimentation was impaired in the peripheral tiers of the ospin1b root cap columella cell, while it was not the main contributor to the abnormal root gravitropism. These data suggest that OsPIN1b not only plays a vital role in regulating rice architecture but also functions in regulating root gravitropism by the integration of light and nutrient signals.
PMID: 36012245
Int J Mol Sci , IF:5.923 , 2022 Aug , V23 (15) doi: 10.3390/ijms23158643
GmIAA27 Encodes an AUX/IAA Protein Involved in Dwarfing and Multi-Branching in Soybean.
College of Agriculture, Northeast Agricultural University, Harbin 150030, China.; National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.; Institute of Plant Virology, Ningbo University, Ningbo 315211, China.
Soybean plant height and branching affect plant architecture and yield potential in soybean. In this study, the mutant dmbn was obtained by treating the cultivar Zhongpin 661 with ethylmethane sulfonate. The dmbn mutant plants were shorter and more branched than the wild type. The genetic analysis showed that the mutant trait was controlled by a semi-dominant gene. The candidate gene was fine-mapped to a 91 kb interval on Chromosome 9 by combining BSA-seq and linkage analysis. Sequence analysis revealed that Glyma.09g193000 encoding an Aux/IAA protein (GmIAA27) was mutated from C to T in the second exon of the coding region, resulting to amino acid substitution of proline to leucine. Overexpression of the mutant type of this gene in Arabidopsis thaliana inhibited apical dominance and promoted lateral branch development. Expression analysis of GmIAA27 and auxin response genes revealed that some GH3 genes were induced. GmIAA27 relies on auxin to interact with TIR1, whereas Gmiaa27 cannot interact with TIR1 owing to the mutation in the degron motif. Identification of this unique gene that controls soybean plant height and branch development provides a basis for investigating the mechanisms regulating soybean plant architecture development.
PMID: 35955771
Int J Mol Sci , IF:5.923 , 2022 Aug , V23 (15) doi: 10.3390/ijms23158593
Fluorescent Auxin Analogs Report Two Auxin Binding Sites with Different Subcellular Distribution and Affinities: A Cue for Non-Transcriptional Auxin Signaling.
Molecular Cell Biology, Botanical Institute, Karlsruhe Institute of Technology, Fritz-Haber-Weg 4, 76133 Karlsruhe, Germany.; Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510301, China.; Department of Biochemistry, Okayama University of Science, 1-1 Ridai-cho, Okayama 700-0005, Japan.
The complexity of auxin signaling is partially due to multiple auxin receptors that trigger differential signaling. To obtain insight into the subcellular localization of auxin-binding sites, we used fluorescent auxin analogs that can undergo transport but do not deploy auxin signaling. Using fluorescent probes for different subcellular compartments, we can show that the fluorescent analog of 1-naphthaleneacetic acid (NAA) associates with the endoplasmic reticulum (ER) and tonoplast, while the fluorescent analog of indole acetic acid (IAA) binds to the ER. The binding of the fluorescent NAA analog to the ER can be outcompeted by unlabeled NAA, which allows us to estimate the affinity of NAA for this binding site to be around 1 muM. The non-transportable auxin 2,4-dichlorophenoxyacetic acid (2,4-D) interferes with the binding site for the fluorescent NAA analog at the tonoplast but not with the binding site for the fluorescent IAA analog at the ER. We integrate these data into a working model, where the tonoplast hosts a binding site with a high affinity for 2,4-D, while the ER hosts a binding site with high affinity for NAA. Thus, the differential subcellular localization of binding sites reflects the differential signaling in response to these artificial auxins.
PMID: 35955725
PLoS Genet , IF:5.917 , 2022 Sep , V18 (9) : Pe1010375 doi: 10.1371/journal.pgen.1010375
SAUR63 stimulates cell growth at the plasma membrane.
Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America.; Laboratoire Reproduction et Developpement des Plantes, Universite de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, Lyon, France.; Department of Plant and Microbial Biology, University of Minnesota, St. Paul, Minnesota, United States of America.
In plants, regulated cell expansion determines organ size and shape. Several members of the family of redundantly acting Small Auxin Up RNA (SAUR) proteins can stimulate plasma membrane (PM) H+-ATPase proton pumping activity by inhibiting PM-associated PP2C.D phosphatases, thereby increasing the PM electrochemical potential, acidifying the apoplast, and stimulating cell expansion. Similarly, Arabidopsis thaliana SAUR63 was able to increase growth of various organs, antagonize PP2C.D5 phosphatase, and increase H+-ATPase activity. Using a gain-of-function approach to bypass genetic redundancy, we dissected structural requirements for SAUR63 growth-promoting activity. The divergent N-terminal domain of SAUR63 has a predicted basic amphipathic alpha-helix and was able to drive partial PM association. Deletion of the N-terminal domain decreased PM association of a SAUR63 fusion protein, as well as decreasing protein level and eliminating growth-promoting activity. Conversely, forced PM association restored ability to promote H+-ATPase activity and cell expansion, indicating that SAUR63 is active when PM-associated. Lipid binding assays and perturbations of PM lipid composition indicate that the N-terminal domain can interact with PM anionic lipids. Mutations in the conserved SAUR domain also reduced PM association in root cells. Thus, both the N-terminal domain and the SAUR domain may cooperatively mediate the SAUR63 PM association required to promote growth.
PMID: 36121899
Front Plant Sci , IF:5.753 , 2022 , V13 : P958808 doi: 10.3389/fpls.2022.958808
Comparative transcriptomics analysis of developing peanut (Arachis hypogaea L.) pods reveals candidate genes affecting peanut seed size.
School of Life Sciences, Zhengzhou University, Zhengzhou, Henan, China.; Henan Academy of Agricultural Sciences, Henan Academy of Crop Molecular Breeding, State Industrial Innovation Center of Biological Breeding, Key Laboratory of Oil Crops in Huang-Huai-Hai Plains, Ministry of Agriculture, Henan Provincial Key Laboratory for Oil Crops Improvement, Innovation Base of Zhengzhou University, Zhengzhou, Henan, China.; College of Agronomy, Henan Agricultural University, Zhengzhou, Henan, China.; College of Agriculture, Henan University of Science and Technology, Luoyang, China.; School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan, China.
Pod size is one of the most important agronomic features of peanuts, which directly affects peanut yield. Studies on the regulation mechanism underpinning pod size in cultivated peanuts remain hitherto limited compared to model plant systems. To better understand the molecular elements that underpin peanut pod development, we conducted a comprehensive analysis of chronological transcriptomics during pod development in four peanut accessions with similar genetic backgrounds, but varying pod sizes. Several plant transcription factors, phytohormones, and the mitogen-activated protein kinase (MAPK) signaling pathways were significantly enriched among differentially expressed genes (DEGs) at five consecutive developmental stages, revealing an eclectic range of candidate genes, including PNC, YUC, and IAA that regulate auxin synthesis and metabolism, CYCD and CYCU that regulate cell differentiation and proliferation, and GASA that regulates seed size and pod elongation via gibberellin pathway. It is plausible that MPK3 promotes integument cell division and regulates mitotic activity through phosphorylation, and the interactions between these genes form a network of molecular pathways that affect peanut pod size. Furthermore, two variant sites, GCP4 and RPPL1, were identified which are stable at the QTL interval for seed size attributes and function in plant cell tissue microtubule nucleation. These findings may facilitate the identification of candidate genes that regulate pod size and impart yield improvement in cultivated peanuts.
PMID: 36172561
Front Plant Sci , IF:5.753 , 2022 , V13 : P927662 doi: 10.3389/fpls.2022.927662
Auxin-regulated timing of transition from vegetative to reproductive growth in rapeseed (Brassica napus L.) under different nitrogen application rates.
Institute of Crops and Nuclear Technology Utilization, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.; Huzhou Agricultural Science and Technology Development Center, Huzhou, China.; Institute of Digital Agriculture, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
Accelerating the differentiation of floral meristem (FM) from shoot apical meristems (SAM) which determines the conversion from vegetative to reproductive growth is of great significance for the production of rapeseed (Brassica napus L.). In this research, the mechanisms of different nitrogen (N) application rates (low N, N1; normal N, N2; and high N, N3) on different FM development stages triggering the regulation of FM differentiation genes through the auxin biosynthetic and signal transduction were investigated. We found that the stage of FM differentiation, which was identified through a stereomicroscope and scanning electron microscope, came 4 and 7 days earlier under high N rate than under normal and low N levels, with the seed yield increased by 11.1 and 22.6%, respectively. Analysis of the auxin and its derivatives contents showed that the main biosynthesis way of auxin was the indole acetaldehyde oxime (IAOx) pathway, with 3-Indole acetonitrile dramatically accumulated during FM differentiation. At the same time, an obvious decrease of IAA contents at each FM differentiation stage was detected, and then gradually rose. Results of the expression of genes involved in auxin biosynthesis, auxin signaling transduction, and FM identification under five FM differentiation stages and three nitrogen application rates showed that genes involved in auxin biosynthesis were regulated before the FM differentiation stage, while the regulation of FM identity genes appeared mainly at the middle and later periods of the five stages, and the regulation level of genes varied under different N rates. Taken together, a high nitrogen rate could accelerate the initiation of FM differentiation, and auxin involved a lot in this regulation.
PMID: 36161032
Front Plant Sci , IF:5.753 , 2022 , V13 : P931063 doi: 10.3389/fpls.2022.931063
Euryale Small Auxin Up RNA62 promotes cell elongation and seed size by altering the distribution of indole-3-acetic acid under the light.
School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, China.; Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing, China.
Euryale (Euryale ferox Salisb.) is an aquatic crop used as both food and drug in Asia, but its utilization is seriously limited due to low yield. Previously, we hypothesized that Euryale small auxin up RNAs (EuSAURs) regulate seed size, but the underlying biological functions and molecular mechanisms remain unclear. Here, we observed that the hybrid Euryale lines (HL) generate larger seeds with higher indole-3-acetic acid (IAA) concentrations than those in the North Gordon Euryale (WT). Histological analysis suggested that a larger ovary in HL is attributed to longer cells around. Overexpression of EuSAUR62 in rice (Oryza sativa L.) resulted in larger glumes and grains and increased the length of glume cells. Immunofluorescence and protein interaction assays revealed that EuSAUR62 modulates IAA accumulation around the rice ovary by interacting with the rice PIN-FORMED 9, an auxin efflux carrier protein. Euryale basic region/leucine zipper 55 (EubZIP55), which was highly expressed in HL, directly binds to the EuSAUR62 promoter and activated the expression of EuSAUR62. Constant light increased the expression of both EubZIP55 and EuSAUR62 with auxin-mediated hook curvature in HL seedlings. Overall, we proposed that EuSAUR62 is a molecular bridge between light and IAA and plays a crucial role in regulating the size of the Euryale seed.
PMID: 36160968
Front Plant Sci , IF:5.753 , 2022 , V13 : P958833 doi: 10.3389/fpls.2022.958833
LsARF3 mediates thermally induced bolting through promoting the expression of LsCO in lettuce (Lactuca sativa L.).
Beijing Key Laboratory of New Technology in Agricultural Application, National Demonstration Center for Experimental Plant Production Education, Plant Science and Technology College, Beijing University of Agriculture, Beijing, China.; National Engineering Research Center for Vegetables, Institute of Vegetable Science, Beijing Academy of Agriculture and Forestry Sciences, Beijing, China.
Lettuce (Lactuca sativa L.) is a leafy vegetable whose edible organs usually are leaf or stems, and thus high-temperature induced bolting followed by flower initiation is an undesirable trait in lettuce production. However, the molecular mechanism that controls lettuce bolting and flowering upon thermal treatments is largely unknown. Here, we identified a Lettuce auxin response factor 3 (LsARF3), the expression of which was enhanced by heat and auxin treatments. Interestingly, LsARF3 is preferentially expressed in stem apex, suggesting it might be associated with lettuce bolting. Transgenic lettuce overexpressing LsARF3 displayed early bolting and flowering, whereas knockout of LsARF3 dramatically delayed bolting and flowering in lettuce under normal or high temperature conditions. Furthermore, Exogenous application of IAA failed to rescue the late-bolting and -flowering phenotype of lsarf3 mutants. Several floral integrator genes including LsCO, LsFT, and LsLFY were co-expressed with LsARF3 in the overexpression and knockout lettuce plants. Yeast one-hybrid (Y1H) experiments suggested that LsARF3 could physically interact with the LsCO promoter, which was further confirmed by a dual luciferase assay in tobacco leaves. The results indicated that LsARF3 might directly modulate the expression of LsCO in lettuce. Therefore, these results demonstrate that LsARF3 could promote lettuce bolting in response to the high temperature by directly or indirectly activating the expression of floral genes such as LsCO, which provides new insights into lettuce bolting in the context of ARFs signaling and heat response.
PMID: 36160965
Front Plant Sci , IF:5.753 , 2022 , V13 : P961658 doi: 10.3389/fpls.2022.961658
Characteristics of members of IGT family genes in controlling rice root system architecture and tiller development.
College of Plant Protection, Yunnan Agricultural University, Kunming, China.; State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, China.; Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University, Kunming, China.; Division of Life Sciences and Medicine, College of Life Sciences, University of Science and Technology of China, Hefei, China.; CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, China.; Yuguopu District Agricultural Comprehensive Service Center, Mengzi, China.
Root system architecture (RSA) and tiller are important agronomic traits. However, the mechanisms of the IGT family genes regulate RSA and tiller development in different rice varieties remain unclear. In this study, we demonstrated that 38 rice varieties obtained from Yuanyang Hani's terraced fields with different RSA and could be classified into six groups based on the ratio of root length and width. We found a positive correlation between RSA (including root width, length, and area) and tiller number in most of rice varieties. Furthermore, the IGT family genes Deeper Rooting 1 (DRO1), LAZY1, TAC1, and qSOR1 showed different expression patterns when rice grown under irrigation and drought conditions. Moreover, the qSOR1 gene had higher levels in the roots and tillers, and accompanied with higher levels of PIN1b gene in roots when rice grown under drought environmental condition. DRO1 gene had two single nucleotide polymorphisms (SNPs) in the exon 3 sequences and showed different expression patterns in the roots and tillers of the 38 rice varieties. Overexpression of DRO1 with a deletion of exon 5 caused shorter root length, less lateral roots and lower levels of LAZY1, TAC1, and qSOR1. Further protein interaction network, microRNA targeting and co-expression analysis showed that DRO1 plays a critical role in the root and tiller development associated with auxin transport. These data suggest that the RSA and tiller development are regulated by the IGT family genes in an intricate network way, which is tightly related to rice genetic background in rice adapting to different environmental conditions.
PMID: 36147240
Front Plant Sci , IF:5.753 , 2022 , V13 : P983650 doi: 10.3389/fpls.2022.983650
An APETALA2/ethylene responsive factor transcription factor GmCRF4a regulates plant height and auxin biosynthesis in soybean.
National Center for Soybean Improvement, Key Laboratory of Biology and Genetics and Breeding for Soybean, Ministry of Agriculture and Rural Affairs, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, China.; The National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI), Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China.
Plant height is one of the key agronomic traits affecting soybean yield. The cytokinin response factors (CRFs), as a branch of the APETALA2/ethylene responsive factor (AP2/ERF) super gene family, have been reported to play important roles in regulating plant growth and development. However, their functions in soybean remain unknown. This study characterized a soybean CRF gene named GmCRF4a by comparing the performance of the homozygous Gmcrf4a-1 mutant, GmCRF4a overexpression (OX) and co-silencing (CS) lines. Phenotypic analysis showed that overexpression of GmCRF4a resulted in taller hypocotyls and epicotyls, more main stem nodes, and higher plant height. While down-regulation of GmCRF4a conferred shorter hypocotyls and epicotyls, as well as a reduction in plant height. The histological analysis results demonstrated that GmCRF4a promotes epicotyl elongation primarily by increasing cell length. Furthermore, GmCRF4a is required for the expression of GmYUCs genes to elevate endogenous auxin levels, which may subsequently enhance stem elongation. Taken together, these observations describe a novel regulatory mechanism in soybean, and provide the basis for elucidating the function of GmCRF4a in auxin biosynthesis pathway and plant heigh regulation in plants.
PMID: 36147224
Front Plant Sci , IF:5.753 , 2022 , V13 : P998698 doi: 10.3389/fpls.2022.998698
Study on exogenous application of thidiazuron on seed size of Brassica napus L.
Engineering Research Center of Ecology and Agricultural Use of Wetland, Ministry of Education, Hubei Key Laboratory of Waterlogging Disaster and Agricultural Use of Wetland, Yangtze University, Hubei, China.; College of Life Science, Yangtze University, Hubei, China.; College of Agriculture, Yangtze University, Hubei, China.; Hubei Key Laboratory of Food Crop Germplasm and Genetic Improvement, Hubei, China.
Thidiazuron (TDZ) is a novel and efficient cytokinin commonly used in tissue culture, and numerous studies have demonstrated that TDZ can increase berry size. However, no study to date has explored the effect of TDZ on seed size of Brassica napus and the mechanism. To shed light on the effect of TDZ on the seed size of B. napus, four different concentrations of TDZ were applied to B. napus. Results indicated that TDZ treatment could increase the seed diameter and silique length of B. napus to varying degrees and 100 and 200 mumol/L TDZ treatments were the most effective with a 3.6 and 4.6% increase in seed diameter, respectively. In addition, the yield of B. napus was also substantially increased under TDZ treatment. On the other hand, confocal micrographs of embryos and cotyledon cells suggested that embryos and their cotyledon epidermal cells treated with 200 mumol/L TDZ were obviously larger in size than the control. Furthermore, TDZ promoted the upregulation of some key maternal tissue growth-related genes, including two G-protein signaling genes (AGG3 and RGA1) and two transcriptional regulators (ANT and GS2). The expression analysis of genes related to the auxin metabolic pathways, G-protein signaling, endosperm growth and transcriptional regulators confirmed that treatment with TDZ negatively regulated the key genes ABI5, AGB1, AP2, ARF2, and ARF18 during bud development stage and florescence. The results strongly suggested that TDZ might regulate the transcriptional levels of key genes involved in auxin metabolic pathways, G-protein signaling, endosperm growth and transcriptional regulators, which resulted in bigger cotyledon epidermal cells and seed size in B. napus. This study explored the mechanism of TDZ treatment on the seed size of B. napus and provided an important reference for improving rapeseed yield.
PMID: 36147221
Front Plant Sci , IF:5.753 , 2022 , V13 : P980138 doi: 10.3389/fpls.2022.980138
Auxin and cytokinin control fate determination of cotyledons in the one-leaf plant Monophyllaea glabra.
Graduate School of Science, The University of Tokyo, Tokyo, Japan.
One-leaf plants in the Gesneriaceae family initially have two cotyledons of identical size; one cotyledon stops growing shortly after germination, whereas the other continues indeterminate growth. Factors involved in the unequal growth have been investigated, and a competitive relationship between the two cotyledons was previously proposed. However, questions regarding the fate determination of the two cotyledons remain: Why does only one cotyledon grow indeterminately while the other stops; is the fate of the cotyledons reversible; and what role does light quality play in the fate determination of the cotyledons? In this study, physiological experiments using the one-leaf plant species Monophyllaea glabra suggest that a biased auxin concentration between the two cotyledons and subsequent cytokinin levels may determine the fate of the cotyledons. In addition, observation of relatively mature individuals without hormone treatment and younger individuals with cytokinin treatment under laboratory growth conditions revealed that the fate determination of the microcotyledon is reversible. Although light quality has been suggested to be important for the determination of cotyledon fate in Streptocarpus rexii, an anisocotylous species, we conclude that light quality is not important in M. glabra.
PMID: 36119619
Front Plant Sci , IF:5.753 , 2022 , V13 : P971773 doi: 10.3389/fpls.2022.971773
A shoot derived long distance iron signal may act upstream of the IMA peptides in the regulation of Fe deficiency responses in Arabidopsis thaliana roots.
Department of Agronomy (DAUCO-Maria de Maeztu Unit of Excellence), Campus de Excelencia Internacional Agroalimentario, Universidad de Cordoba, Cordoba, Spain.; Department of Botany, Ecology and Plant Physiology, Campus de Excelencia Internacional Agroalimentario, Universidad de Cordoba, Cordoba, Spain.
When plants suffer from Fe deficiency, they develop morphological and physiological responses, mainly in their roots, aimed to facilitate Fe mobilization and uptake. Once Fe has been acquired in sufficient quantity, the responses need to be switched off to avoid Fe toxicity and to conserve energy. Several hormones and signaling molecules, such as ethylene, auxin and nitric oxide, have been involved in the activation of Fe deficiency responses in Strategy I plants. These hormones and signaling molecules have almost no effect when applied to plants grown under Fe-sufficient conditions, which suggests the existence of a repressive signal related to the internal Fe content. The nature of this repressive signal is not known yet many experimental results suggest that is not related to the whole root Fe content but to some kind of Fe compound moving from leaves to roots through the phloem. After that, this signal has been named LOng-Distance Iron Signal (LODIS). Very recently, a novel family of small peptides, "IRON MAN" (IMA), has been identified as key components of the induction of Fe deficiency responses. However, the relationship between LODIS and IMA peptides is not known. The main objective of this work has been to clarify the relationship between both signals. For this, we have used Arabidopsis wild type (WT) Columbia and two of its mutants, opt3 and frd3, affected, either directly or indirectly, in the transport of Fe (LODIS) through the phloem. Both mutants present constitutive activation of Fe acquisition genes when grown in a Fe-sufficient medium despite the high accumulation of Fe in their roots. Arabidopsis WT Columbia plants and both mutants were treated with foliar application of Fe, and later on the expression of IMA and Fe acquisition genes was analyzed. The results obtained suggest that LODIS may act upstream of IMA peptides in the regulation of Fe deficiency responses in roots. The possible regulation of IMA peptides by ethylene has also been studied. Results obtained with ethylene precursors and inhibitors, and occurrence of ethylene-responsive cis-acting elements in the promoters of IMA genes, suggest that IMA peptides could also be regulated by ethylene.
PMID: 36105702
Front Plant Sci , IF:5.753 , 2022 , V13 : P959693 doi: 10.3389/fpls.2022.959693
Transcriptome analysis revealed the expression levels of genes related to abscisic acid and auxin biosynthesis in grapevine (Vitis vinifera L.) under root restriction.
Department of Plant Science, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China.
The root system is essential for the stable growth of plants. Roots help anchor plants in the soil and play a crucial role in water uptake, mineral nutrient absorption and endogenous phytohormone formation. Root-restriction (RR) cultivation, a powerful technique, confines plant roots to a specific soil space. In the present study, roots of one-year-old "Muscat Hamburg" grapevine under RR and control (nR) treatments harvested at 70 and 125 days after planting were used for transcriptome sequencing, and in total, 2031 (nR7 vs. nR12), 1445 (RR7 vs. RR12), 1532 (nR7 vs. RR7), and 2799 (nR12 vs. RR12) differentially expressed genes (DEGs) were identified. Gene Ontology (GO) enrichment analysis demonstrated that there were several genes involved in the response to different phytohormones, including abscisic acid (ABA), auxin (IAA), ethylene (ETH), gibberellins (GAs), and cytokinins (CTKs). Among them, multiple genes, such as PIN2 and ERF113, are involved in regulating vital plant movements by various phytohormone pathways. Moreover, following RR cultivation, DEGs were enriched in the biological processes of plant-type secondary cell wall biosynthesis, the defense response, programmed cell death involved in cell development, and the oxalate metabolic process. Furthermore, through a combined analysis of the transcriptome and previously published microRNA (miRNA) sequencing results, we found that multiple differentially expressed miRNAs (DEMs) and DEG combinations in different comparison groups exhibited opposite trends, indicating that the expression levels of miRNAs and their target genes were negatively correlated. Furthermore, RR treatment indeed significantly increased the ABA content at 125 days after planting and significantly decreased the IAA content at 70 days after planting. Under RR cultivation, most ABA biosynthesis-related genes were upregulated, while most IAA biosynthesis-related genes were downregulated. These findings lay a solid foundation for further establishing the network through which miRNAs regulate grapevine root development through target genes and for further exploring the molecular mechanism through which endogenous ABA and IAA regulate root architecture development in grapevine.
PMID: 36092429
Front Plant Sci , IF:5.753 , 2022 , V13 : P982853 doi: 10.3389/fpls.2022.982853
CkREV regulates xylem vessel development in Caragana korshinskii in response to drought.
College of Horticulture, Northwest A&F University, Xianyang, Shaanxi, China.; College of Life Sciences, Northwest A&F University, Xianyang, Shaanxi, China.
Drought stress poses severe threat to the development and even the survival status of plants. Plants utilize various methods responding to drought, among which the forming of more well-developed xylem in leaf vein in woody plants deserves our attention. Herein, we report a transcription factor CkREV from HD-ZIP III family in Caragana korshinskii, which possesses significant functions in drought response by regulating xylem vessel development in leaf vein. Research reveal that in C. korshinskii the expression level of CkREV located in xylem vessel and adjacent cells will increase as the level of drought intensifies, and can directly induce the expression of CkLAX3, CkVND6, CkVND7, and CkPAL4 by binding to their promoter regions. In Arabidopsis thaliana, CkREV senses changes in drought stress signals and bidirectionally regulates the expression of related genes to control auxin polar transport, vessel differentiation, and synthesis of cell wall deposits, thereby significantly enhancing plant drought tolerance. In conclusion, our findings offer a novel understanding of the regulation of CkREV, a determinant of leaf adaxial side, on the secondary development of xylem vessels in leaf vein to enhance stress tolerance in woody plants.
PMID: 36092404
Front Plant Sci , IF:5.753 , 2022 , V13 : P910369 doi: 10.3389/fpls.2022.910369
Transcriptome analysis of the 2,4-dichlorophenoxyacetic acid (2,4-D)-tolerant cotton chromosome substitution line CS-B15sh and its susceptible parental lines G. hirsutum L. cv. Texas Marker-1 and G. barbadense L. cv. Pima 379.
Department of Biochemistry, Molecular Biology, Entomology & Plant Pathology, Mississippi State University, Starkville, MS, United States.; Faculty of Science and Engineering, Southern Cross University, East Lismore, NSW, Australia.; Institute for Genomics, Biocomputing and Biotechnology, Mississippi State University, Starkville, MS, United States.; Department of Plant and Soil Sciences, Mississippi State University, Starkville, MS, United States.
The cotton chromosome substitution line, CS-B15sh, exhibits 41% lower injury from 2,4-D when applied at the field recommended rate of 1.12 kg ae ha(-1) (1x) than does Texas Marker-1 (TM-1). CS-B15sh was developed in the genetic background of Gossypium hirsutum L. cv TM-1 and has chromosome introgression on the short arm of chromosome 15 from Gossypium barbadense L. cv. Pima 379. In a previous experiment, we observed reduced translocation of [(14)C]2,4-D outside the treated leaf tissue in CS-B15sh, which contrasted with an increased translocation of the herbicide in the tissues above and below the treated leaf in TM-1. Our results indicate a potential 2,4-D tolerance mechanism in CS-B15sh involving altered movement of 2,4-D. Here, we used RNA sequencing (RNA-seq) to determine the differential expression of genes between 2,4-D-challenged and control plants of the tolerant (CS-B15sh) and susceptible lines (TM-1 and Pima 379). Several components of the 2,4-D/auxin-response pathway-including ubiquitin E3 ligase, PB1|AUX/IAA, ARF transcription factors, and F-box proteins of the SCF(TIR1/AFB) complex-were upregulated with at least threefold higher expression in TM-1 compared with CS-B15sh, while both Pima 379 and TM-1 showed the same fold change expression for PB1|AUX/IAA mRNA. Some genes associated with herbicide metabolism, including flavin monooxygenase (Gohir.A01G174100) and FAD-linked oxidase (Gohir.D06G002600), exhibited at least a twofold increase in CS-B15sh than in TM-1 (the gene was not expressed in Pima 379), suggesting a potential relationship between the gene's expression and 2,4-D tolerance. It is interesting to note that glutathione S-transferase was differentially expressed in both CS-B15sh and Pima 379 but not in TM-1, while cytochrome P450 and other genes involved in the oxidation-reduction process were significantly expressed only in CS-B15sh in response to 2,4-D. Gene set enrichment analysis on the union DEGs of the three cotton genotypes revealed the depletion of transcripts involved in photosynthesis and enrichment of transcripts involved in ABA response and signaling.
PMID: 36072333
Front Plant Sci , IF:5.753 , 2022 , V13 : P980033 doi: 10.3389/fpls.2022.980033
Bidirectional mRNA transfer between Cuscuta australis and its hosts.
Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China.
The holoparasitic dodder (Cuscuta spp.) is able to transfer mRNA and certain plant pathogens (e.g., viruses and bacteria) from the host plant. "Candidatus Liberibacter asiaticus," the phloem-limited causative agent of citrus Huanglongbing, can be transferred from citrus to periwinkle (Catharanthus roseus) mediated by dodder. However, characterization of mRNA transport between dodder and citrus/periwinkle remains unclear. In this study, we sequenced transcriptomes of dodder and its parasitizing host, sweet orange (Citrus sinensis "Newhall") and periwinkle (Catharanthus roseus), to identify and characterize mRNA transfer between dodder and the host plant during parasitism. The mRNA transfer between dodder and citrus/periwinkle was bidirectional and most of the transfer events occurred in the interface tissue. Compared with the citrus-dodder system, mRNA transfer in the periwinkle-dodder system was more frequent. Function classification revealed that a large number of mRNAs transferred between dodder and citrus/periwinkle were involved in secondary metabolism and stress response. Dodder transcripts encoding proteins associated with microtubule-based processes and cell wall biogenesis were transferred to host tissues. In addition, transcripts involved in translational elongation, plasmodesmata, and the auxin-activated signaling pathway were transmitted between dodder and citrus/periwinkle. In particular, transcripts involved in shoot system development and flower development were transferred between the host and dodder in both directions. The high abundance of dodder-origin transcripts, encoding MIP aquaporin protein, and S-adenosylmethionine synthetase 1 protein, in citrus and periwinkle tissues indicated they could play an important biological role in dodder-host interaction. In addition, the uptake of host mRNAs by dodder, especially those involved in seed germination and flower development, could be beneficial for the reproduction of dodder. The results of this study provide new insights into the RNA-based interaction between dodder and host plants.
PMID: 36072332
Front Plant Sci , IF:5.753 , 2022 , V13 : P954788 doi: 10.3389/fpls.2022.954788
Morpho-histology, endogenous hormone dynamics, and transcriptome profiling in Dacrydium pectinatum during female cone development.
Key Laboratory of Ministry of Education for Genetics and Germplasm Innovation of Tropical Special Trees and Ornamental Plants, Key Laboratory of Germplasm Resources Biology of Tropical Special Ornamental Plants of Hainan Province, College of Forestry, Hainan University, Haikou, China.; Department of Genetics and Biochemistry, Clemson University, Clemson, SC, United States.
Dacrydium pectinatum de Laubenfels is a perennial dioeciously gymnosperm species dominant in tropical montane rain forests. Due to deforestation, natural disasters, long infancy, and poor natural regeneration ability, the population of this species has been significantly reduced and listed as an endangered protected plant. To better understand the female cone development in D. pectinatum, we examined the morphological and anatomical changes, analyzed the endogenous hormone dynamics, and profiled gene expression. The female reproductive structures were first observed in January. The morpho-histological observations suggest that the development of the D. pectinatum megaspore can be largely divided into six stages: early flower bud differentiation, bract primordium differentiation, ovule primordium differentiation, dormancy, ovule maturity, and seed maturity. The levels of gibberellins (GA), auxin (IAA), abscisic acid (ABA), and cytokinin (CTK) fluctuate during the process of female cone development. The female cones of D. pectinatum need to maintain a low level of GA3-IAA-ABA steady state to promote seed germination. The first transcriptome database for female D. pectinatum was generated, revealing 310,621 unigenes. Differential expression analyses revealed several floral (MADS2, AGL62, and LFY) and hormone biosynthesis and signal transduction (CKX, KO, KAO, ABA4, ACO, etc.) genes that could be critical for female cone development. Our study provides new insights into the cone development in D. pectinatum and the foundation for female cone induction with hormones.
PMID: 36061797
Front Plant Sci , IF:5.753 , 2022 , V13 : P978013 doi: 10.3389/fpls.2022.978013
The molecular mechanism on suppression of climacteric fruit ripening with postharvest wax coating treatment via transcriptome.
Key Laboratory of Fruit Postharvest Biology (Liaoning Province), Key Laboratory of Protected Horticulture (Ministry of Education), National and Local Joint Engineering Research Center of Northern Horticultural Facilities Design and Application Technology (Liaoning), College of Horticulture, Shenyang Agricultural University, Shenyang, China.; Liaoning Institute of Pomology, Xiongyue, China.; Mudanjiang Branch, Heilongjiang Academy of Agricultural Sciences, Mudanjiang, China.
Wax coating is an important means to maintain fruit quality and extend fruit shelf life, especially for climacteric fruits, such as apples (Malus domestica). Here, we found that wax coating could inhibit ethylene production, chlorophyll degradation, and carotenoid synthesis, but the molecular mechanism remains unclear. The regulatory mechanism of wax coating on apple fruit ripening was determined by subjecting wax-treated apple fruits to transcriptome analysis. RNA-seq revealed that 1,137 and 1,398 genes were upregulated and downregulated, respectively. These differentially expressed genes (DEGs) were shown to be related to plant hormones, such as ethylene, auxin, abscisic acid, and gibberellin, as well as genes involved in chlorophyll degradation and carotenoid biosynthesis. Moreover, we found that some genes related to the wax synthesis process also showed differential expression after the wax coating treatment. Among the DEGs obtained from RNA-seq analysis, 15 were validated by quantitative RT-PCR, confirming the results from RNA-seq analysis. RNA-seq and qRT-PCR of pear (Pyrus ussuriensis) showed similar changes after wax treatment. Our data suggest that wax coating treatment inhibits fruit ripening through ethylene synthesis and signal transduction, chlorophyll metabolism, and carotenoid synthesis pathways and that waxing inhibits endogenous wax production. These results provide new insights into the inhibition of fruit ripening by wax coating.
PMID: 36046594
Front Plant Sci , IF:5.753 , 2022 , V13 : P948901 doi: 10.3389/fpls.2022.948901
Distinct GmASMTs are involved in regulating transcription factors and signalling cross-talk across embryo development, biotic, and abiotic stress in soybean.
Plant Cell Biotechnology Department, CSIR-Central Food Technological Research Institute, Mysore, Karnataka, India.; Indian Institute of Science Education and Research, Bhopal, Madhya Pradesh, India.
N-Acetylserotonin O-methyltransferase (ASMT) is the final enzyme involved in melatonin biosynthesis. Identifying the expression of ASMT will reveal the regulatory role in the development and stress conditions in soybean. To identify and characterize ASMT in soybean (GmASMT), we employed genome-wide analysis, gene structure, cis-acting elements, gene expression, co-expression network analysis, and enzyme assay. We found seven pairs of segmental and tandem duplication pairs among the 44 identified GmASMTs by genome-wide analysis. Notably, co-expression network analysis reported that distinct GmASMTs are involved in various stress response. For example, GmASMT3, GmASMT44, GmASMT17, and GmASMT7 are involved in embryo development, heat, drought, aphid, and soybean cyst nematode infections, respectively. These distinct networks of GmASMTs were associated with transcription factors (NAC, MYB, WRKY, and ERF), stress signalling, isoflavone and secondary metabolites, calcium, and calmodulin proteins involved in stress regulation. Further, GmASMTs demonstrated auxin-like activities by regulating the genes involved in auxin transporter (WAT1 and NRT1/PTR) and auxin-responsive protein during developmental and biotic stress. The current study identified the key regulatory role of GmASMTs during development and stress. Hence GmASMT could be the primary target in genetic engineering for crop improvement under changing environmental conditions.
PMID: 36035712
Front Plant Sci , IF:5.753 , 2022 , V13 : P944515 doi: 10.3389/fpls.2022.944515
Regulation of plant biotic interactions and abiotic stress responses by inositol polyphosphates.
Departmentof Plant Nutrition, Institute of Crop Science and Resource Conservation, Rheinische Friedrich-Wilhelms-Universitat Bonn, Bonn, Germany.; Department of Biochemistry, Indian Institute of Science, Bengaluru, India.; Department of Chemistry and Pharmacy & CIBSS - The Center of Biological Signaling Studies, Albert-Ludwigs University Freiburg, Freiburg, Germany.
Inositol pyrophosphates (PP-InsPs), derivatives of inositol hexakisphosphate (phytic acid, InsP6) or lower inositol polyphosphates, are energy-rich signaling molecules that have critical regulatory functions in eukaryotes. In plants, the biosynthesis and the cellular targets of these messengers are not fully understood. This is because, in part, plants do not possess canonical InsP6 kinases and are able to synthesize PP-InsP isomers that appear to be absent in yeast or mammalian cells. This review will shed light on recent discoveries in the biosynthesis of these enigmatic messengers and on how they regulate important physiological processes in response to abiotic and biotic stresses in plants.
PMID: 36035672
Front Plant Sci , IF:5.753 , 2022 , V13 : P959053 doi: 10.3389/fpls.2022.959053
The roles of epigenetic modifications in the regulation of auxin biosynthesis.
Ministry of Education (MOE) Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China.; Gansu Province Key Laboratory of Gene Editing for Breeding, School of Life Sciences, Lanzhou University, Lanzhou, China.; State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China.; College of Life Science and Technology, Gansu Agricultural University, Lanzhou, China.; Basic Forestry and Proteomics Research Center, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China.
Auxin is one of the most important plant growth regulators of plant morphogenesis and response to environmental stimuli. Although the biosynthesis pathway of auxin has been elucidated, the mechanisms regulating auxin biosynthesis remain poorly understood. The transcription of auxin biosynthetic genes is precisely regulated by complex signaling pathways. When the genes are expressed, epigenetic modifications guide mRNA synthesis and therefore determine protein production. Recent studies have shown that different epigenetic factors affect the transcription of auxin biosynthetic genes. In this review, we focus our attention on the molecular mechanisms through which epigenetic modifications regulate auxin biosynthesis.
PMID: 36017262
Front Plant Sci , IF:5.753 , 2022 , V13 : P890613 doi: 10.3389/fpls.2022.890613
Melatonin confers fenugreek tolerance to salinity stress by stimulating the biosynthesis processes of enzymatic, non-enzymatic antioxidants, and diosgenin content.
Department of Agronomy and Plant Breeding, Faculty of Agriculture, Shahrood University of Technology, Semnan, Iran.; Department of Plant Production and Genetics, Faculty of Agriculture, Urmia University, Urmia, Iran.
Salinity-induced stress is widely considered a main plant-growth-limiting factor. The positive effects of melatonin in modulating abiotic stresses have led this hormone to be referred to as a growth regulator in plants. This study aims to show how melatonin protects fenugreek against the negative effects of salt stress. Different amounts of melatonin (30, 60, and 90 ppm), salinity stress (150 mM and 300 mM), and the use of both salinity and melatonin were used as treatments. The results showed that applying different melatonin levels to salinity-treated fenugreek plants effectively prevented the degradation of chlorophyll a, chlorophyll b, total chlorophyll, and carotenoid contents compared with salinity treatment without melatonin application. Besides, melatonin increases the biosynthesis of enzymatic and non-enzymatic antioxidants, thereby adjusting the content of reactive oxygen species, free radicals, electrolyte leakage, and malondialdehyde content. It was observed that applying melatonin increased the activity of potassium-carrying channels leading to the maintenance of ionic homeostasis and increased intracellular water content under salinity stress. The results revealed that melatonin activates the defense signaling pathways in fenugreek through the nitric oxide, auxin, and abscisic acid-dependent pathways. Melatonin, in a similar vein, increased the expression of genes involved in the biosynthesis pathway of diosgenin, a highly important steroidal sapogenin in medical and food industries, and hence the diosgenin content. When 150 mM salinity stress and 60 ppm melatonin were coupled, the diosgenin concentration rose by more than 5.5 times compared to the control condition. In conclusion, our findings demonstrate the potential of melatonin to enhance the plant tolerance to salinity stress by stimulating biochemical and physiological changes.
PMID: 36003823
Front Plant Sci , IF:5.753 , 2022 , V13 : P961651 doi: 10.3389/fpls.2022.961651
Halophyte Nitraria billardieri CIPK25 mitigates salinity-induced cell damage by alleviating H2O2 accumulation.
Key Laboratory of Forest Genetics & Biotechnology of Ministry of Education of China, Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China.; Experimental Center of Desert Forestry, Chinese Academy of Forestry, Dengkou, China.; College of Biology and the Environment, Nanjing Forestry University, Nanjing, China.
The plant-specific module of calcineurin B-like proteins (CBLs) and CBL-interacting protein kinases (CIPKs) play a crucial role in plant adaptation to different biotic and abiotic stresses in various plant species. Despite the importance of the CBL-CIPK module in regulating plant salt tolerance, few halophyte CIPK orthologs have been studied. We identified NbCIPK25 in the halophyte Nitraria billardieri as a salt-responsive gene that may improve salt tolerance in glycophytes. Sequence analyses indicated that NbCIPK25 is a typical CIPK family member with a conserved NAF motif, which contains the amino acids: asparagine, alanine, and phenylalanine. NbCIPK25 overexpression in salt-stressed transgenic Arabidopsis seedlings resulted in enhanced tolerance to salinity, a higher survival rate, longer newly grown roots, more root meristem cells, and less damaged root cells in comparison to wild-type (WT) plants. H2O2 accumulation and malondialdehyde (MDA) content were both deceased in NbCIPK25-transgenic plants under salt treatment. Furthermore, their proline content, an important factor for scavenging reactive oxygen species, accumulated at a significantly higher level. In concordance, the transcription of genes related to proline accumulation was positively regulated in transgenic plants under salt condition. Finally, we observed a stronger auxin response in salt-treated transgenic roots. These results provide evidence for NbCIPK25 improving salt tolerance by mediating scavenging of reactive oxygen species, thereby protecting cells from oxidation and maintaining plant development under salt stress. These findings suggest the potential application of salt-responsive NbCIPK25 for cultivating glycophytes with a higher salt tolerance through genetic engineering.
PMID: 36003812
Front Plant Sci , IF:5.753 , 2022 , V13 : P958964 doi: 10.3389/fpls.2022.958964
Molecular evolutionary analysis of the SHI/STY gene family in land plants: A focus on the Brassica species.
School of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, China.
The plant-specific SHORT INTERNODES/STYLISH (SHI/STY) proteins belong to a family of transcription factors that are involved in the formation and development of early lateral roots. However, the molecular evolution of this family is rarely reported. Here, a total of 195 SHI/STY genes were identified in 21 terrestrial plants, and the Brassica species is the focus of our research. Their physicochemical properties, chromosome location and duplication, motif distribution, exon-intron structures, genetic evolution, and expression patterns were systematically analyzed. These genes are divided into four clades (Clade 1/2/3/4) based on phylogenetic analysis. Motif distribution and gene structure are similar in each clade. SHI/STY proteins are localized in the nucleus by the prediction of subcellular localization. Collinearity analysis indicates that the SHI/STYs are relatively conserved in evolution. Whole-genome duplication is the main factor for their expansion. SHI/STYs have undergone intense purifying selection, but several positive selection sites are also identified. Most promoters of SHI/STY genes contain different types of cis-elements, such as light, stress, and hormone-responsive elements, suggesting that they may be involved in many biological processes. Protein-protein interaction predicted some important SHI/STY interacting proteins, such as LPAT4, MBOATs, PPR, and UBQ3. In addition, the RNA-seq and qRT-PCR analysis were studied in detail in rape. As a result, SHI/STYs are highly expressed in root and bud, and can be affected by Sclerotinia sclerotiorum, drought, cold, and heat stresses. Moreover, quantitative real-time PCR (qRT-PCR) analyses indicates that expression levels of BnSHI/STYs are significantly altered in different treatments (cold, salt, drought, IAA, auxin; ABA, abscisic acid; 6-BA, cytokinin). It provides a new understanding of the evolution and expansion of the SHI/STY family in land plants and lays a foundation for further research on their functions.
PMID: 35991428
Front Plant Sci , IF:5.753 , 2022 , V13 : P919290 doi: 10.3389/fpls.2022.919290
Hairy root transformation system as a tool for CRISPR/Cas9-directed genome editing in oilseed rape (Brassica napus).
CEITEC MU - Central European Institute of Technology, Masaryk University, Brno, Czechia.; National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czechia.; Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czechia.
Our study examined the mutation efficiency of the CRISPR/Cas9 method for tryptophan aminotransferase BnaTAA1 genes involved in the auxin biosynthesis pathway. We made nine CRISPR/Cas9 constructs with various promoters driving the expression of a Cas9 from Staphylococcus aureus (SaCas9) or a plant-codon-optimized Streptococcus pyogenes Cas9 (pcoCas9). We developed a fast and efficient system for evaluating the variety and frequency of mutations caused by each construct using Brassica napus hairy roots. We showed that pcoCas9 is more efficient in mutating the targeted loci than SaCas9 and the presence of the NLS signal enhanced the chance of mutagenesis by 25%. The mutations were studied further in regenerated lines, and we determined the BnaTAA1 gene expression and heritability of the gene modifications in transgenic plants. Hairy root transformation combined with CRISPR/Cas9-mediated gene editing represents a fast and straightforward system for studying target gene function in the important oilseed crop B. napus.
PMID: 35991410
Genomics , IF:5.736 , 2022 Sep , V114 (5) : P110465 doi: 10.1016/j.ygeno.2022.110465
Series-temporal transcriptome profiling of cotton reveals the response mechanism of phosphatidylinositol signaling system in the early stage of drought stress.
Institute of Industrial Crops, Shandong Academy of Agricultural Sciences, Key Laboratory of Cotton Breeding and Cultivation in Huang-Huai-Hai Plain, Ministry of Agriculture, Jinan, Shandong 250100, PR China.; Dryland Farming Institute, Hebei Academy of Agricultural and Forestry Sciences, Hebei Key Laboratory of Crops Drought Resistance, Hengshui, Hebei 053000, PR China. Electronic address: daimaohua@sina.com.; Institute of Industrial Crops, Shandong Academy of Agricultural Sciences, Key Laboratory of Cotton Breeding and Cultivation in Huang-Huai-Hai Plain, Ministry of Agriculture, Jinan, Shandong 250100, PR China. Electronic address: zongfuhan@126.com.
Plants are sessile organisms suffering severe environmental conditions. Drought stress is one of the major environmental issues that affect plant growth and productivity. Although complex regulatory gene networks of plants under drought stress have been analyzed extensively, the response mechanism in the early stage of drought stress is still rarely mentioned. Here, we performed transcriptome analyses on cotton samples treated for a short time (10 min, 30 min, 60 min, 180 min) using 10% PEG, which is used to simulate drought stress. The analysis of differently expressed genes (DEGs) showed that the number of DEGs in roots was obviously more than that in stems and leaves at the four time points and maintained >2000 FDEGs (DEGs appearing for the first time) from 10 min, indicating that root tissues of plants respond to drought stress quickly and continuously strongly. Gene ontology (GO) analysis showed that DEGs in roots were mainly enriched in protein modification and microtubule-based process. DEGs were found significantly enriched in phosphatidylinositol signaling system at 10 min through Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, implying the great importance of phosphatidylinositol signal in the early stage of drought stress. What was more, two co-expression modules, which were significantly positively correlated with drought stress, were found by Weighted Gene Co-expression Network Analysis (WGCNA). From one of the co-expression modules, we identified a hub-gene Gohir.A07G058200, which is annotated as "phosphatidylinositol 3- and 4-kinase" in phosphatidylinositol signaling system, and found this gene may interact with auxin-responsive protein. This result suggested that Gohir.A07G058200 may be involved in the crosstalk of phosphatidylinositol signal and auxin signal in the early stage of drought stress. In summary, through transcriptome sequencing, we found that phosphatidylinositol signaling system is an important signal transduction pathway in early stage in response to drought stress, and it may interact with auxin signal transduction through phosphatidylinositol 3- and 4-kinase.
PMID: 36038061
Theor Appl Genet , IF:5.699 , 2022 Oct , V135 (10) : P3611-3628 doi: 10.1007/s00122-022-04205-w
Genetic dissection of morphological variation in rosette leaves and leafy heads in cabbage (Brassica oleracea var. capitata).
Plant Breeding, Wageningen University and Research, Droevendaalsesteeg 1, Wageningen, The Netherlands.; Centre for Crop Systems Analysis, Wageningen University and Research, PO Box 430, 6700 AK, Wageningen, The Netherlands.; Biometris, Wageningen University and Research, Droevendaalsesteeg 1, Wageningen, The Netherlands.; Plant Breeding, Wageningen University and Research, Droevendaalsesteeg 1, Wageningen, The Netherlands. guusje.bonnema@wur.nl.
KEY MESSAGE: Correlations between morphological traits of cabbage rosette leaves and heads were found. Genome-wide association studies of these traits identified 50 robust quantitative trait loci in multiple years. Half of these loci affect both organs. Cabbage (Brassica oleracea var. capitata) is an economically important vegetable crop cultivated worldwide. Cabbage plants go through four vegetative stages: seedling, rosette, folding and heading. Rosette leaves are the largest leaves of cabbage plants and provide most of the energy needed to produce the leafy head. To understand the relationship and the genetic basis of leaf development and leafy head formation, 308 cabbage accessions were scored for rosette leaf and head traits in three-year field trials. Significant correlations were found between morphological traits of rosette leaves and heads, namely leaf area with the head area, height and width, and leaf width with the head area and head height, when heads were harvested at a fixed number of days after sowing. Fifty robust quantitative trait loci (QTLs) for rosette leaf and head traits distributed over all nine chromosomes were identified with genome-wide association studies. All these 50 loci were identified in multiple years and generally affect multiple traits. Twenty-five of the QTL were associated with both rosette leaf and leafy head traits. We discuss thirteen candidate genes identified in these QTL that are expressed in heading leaves, with an annotation related to auxin and other phytohormones, leaf development, and leaf polarity that likely play a role in leafy head development or rosette leaf expansion.
PMID: 36057748
Theor Appl Genet , IF:5.699 , 2022 Oct , V135 (10) : P3497-3510 doi: 10.1007/s00122-022-04196-8
Integrated genetic mapping and transcriptome analysis reveal the BnaA03.IAA7 protein regulates plant architecture and gibberellin signaling in Brassica napus L.
College of Agronomy and Biotechnology, Academy of Agricultural Sciences, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land, Southwest University, Chongqing, 400715, China.; Biotechnology Research Center, Southwest University, Chongqing, 400715, China.; State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, School of Life Sciences, Hubei University, Wuhan, 430070, China.; College of Agronomy and Biotechnology, Academy of Agricultural Sciences, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land, Southwest University, Chongqing, 400715, China. liezhao@swu.edu.cn.
KEY MESSAGE: A novel mutation in the BnaA03.IAA7 protein reduces plant height and enhances gibberellin signaling in Brassica napus L. Rapeseed (Brassica napus) is an excellent and important source for vegetable oil production, but its production is severely affected by lodging. Lodging hinders mechanization and decreases yield, and an ideal solution is semidwarf breeding. Limited by germplasm resources, semidwarf breeding developed slowly in rapeseed. In the current study, a mutant called sdA03 was isolated from EMS-mutagenized lines of Zhongshuang 11 (ZS11). The inheritance analysis showed that phenotypes of sdA03 were controlled by a single semidominant gene. Genetic mapping, RNA-seq and candidate gene analysis identified BnaA03.IAA7 as a candidate gene, and a function test confirmed that the mutated BnaA03.iaa7 regulates plant architecture in a dose-dependent manner. Yeast two-hybrid and transient expression experiments illustrated the P87L substitution in the GWPPV/I degron motif of BnaA03.iaa7 impaired the interaction between BnaA03.IAA7 and TIR1 proteins, and BnaA03.iaa7 prevented ARF from activating the auxin signaling pathway.The gibberellin (GA) content was higher in sdA03 hypocotyls than in those of ZS11. Further expression analysis showed more active gibberellin signaling in hypocotyl and richer expression of GA synthetic genes in root and cotyledon of sdA03 seedlings. Finally, a marker was developed based on the SNP found in BnaA03.iaa7 and used in molecular breeding. The study enriched our understanding of the architectural regulation of rapeseed and provided germplasm resources for breeding.
PMID: 35962210
Mol Plant Pathol , IF:5.663 , 2022 Sep , V23 (9) : P1361-1380 doi: 10.1111/mpp.13234
A novel strategy for improving watermelon resistance to cucumber green mottle mosaic virus by exogenous boron application.
Liaoning Key Laboratory of Plant Pathology, College of Plant Protection, Shenyang Agricultural University, Shenyang, China.; Centre for Biological Disaster Prevention and Control, National Forestry and Grassland Administration, Shenyang, China.; Xinmin City Agricultural Technology Extension Centre, Shenyang, China.
The molecular mode controlling cucumber green mottle mosaic virus (CGMMV)-induced watermelon blood flesh disease (WBFD) is largely unknown. In this study, we have found that application of exogenous boron suppressed CGMMV infection in watermelon fruit and alleviated WBFD symptoms. Our transcriptome analysis showed that the most up-regulated differentially expressed genes (DEGs) were associated with polyamine and auxin biosynthesis, abscisic acid catabolism, defence-related pathways, cell wall modification, and energy and secondary metabolism, while the down-regulated DEGs were mostly involved in ethylene biosynthesis, cell wall catabolism, and plasma membrane functions. Our virus-induced gene silencing results showed that silencing of SPDS expression in watermelon resulted in a higher putrescine content and an inhibited CGMMV infection correlating with no WBFD symptoms. SBT and TUBB1 were also required for CGMMV infection. In contrast, silencing of XTH23 and PE/PEI7 (low-level lignin, cellulose and pectin) and ATPS1 (low-level glutathione) promoted CGMMV accumulation. Furthermore, RAP2-3, MYB6, WRKY12, H2A, and DnaJ11 are likely to participate in host antiviral resistance. In addition, a higher (spermidine + spermine):putrescine ratio, malondialdehyde content, and lactic acid content were responsible for fruit decay and acidification. Our results provide new knowledge on the roles of boron in watermelon resistance to CGMMV-induced WBFD. This new knowledge can be used to design better control methods for CGMMV in the field and to breed CGMMV resistant watermelon and other cucurbit crops.
PMID: 35671152
Front Microbiol , IF:5.64 , 2022 , V13 : P956018 doi: 10.3389/fmicb.2022.956018
The immunity priming effect of the Arabidopsis phyllosphere resident yeast Protomyces arabidopsidicola strain C29.
Organismal and Evolutionary Biology Research Program, Faculty of Biological and Environmental Sciences, and Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland.
The phyllosphere is a complex habitat for diverse microbial communities. Under natural conditions, multiple interactions occur between host plants and phyllosphere resident microbes, such as bacteria, oomycetes, and fungi. Our understanding of plant associated yeasts and yeast-like fungi lags behind other classes of plant-associated microbes, largely due to a lack of yeasts associated with the model plant Arabidopsis, which could be used in experimental model systems. The yeast-like fungal species Protomyces arabidopsidicola was previously isolated from the phyllosphere of healthy wild-growing Arabidopsis, identified, and characterized. Here we explore the interaction of P. arabidopsidicola with Arabidopsis and found P. arabidopsidicola strain C29 was not pathogenic on Arabidopsis, but was able to survive in its phyllosphere environment both in controlled environment chambers in the lab and under natural field conditions. Most importantly, P. arabidopsidicola exhibited an immune priming effect on Arabidopsis, which showed enhanced disease resistance when subsequently infected with the fungal pathogen Botrytis cinerea. Activation of the mitogen-activated protein kinases (MAPK), camalexin, salicylic acid, and jasmonic acid signaling pathways, but not the auxin-signaling pathway, was associated with this priming effect, as evidenced by MAPK3/MAPK6 activation and defense marker expression. These findings demonstrate Arabidopsis immune defense priming by the naturally occurring phyllosphere resident yeast species, P. arabidopsidicola, and contribute to establishing a new interaction system for probing the genetics of Arabidopsis immunity induced by resident yeast-like fungi.
PMID: 36118213
Front Microbiol , IF:5.64 , 2022 , V13 : P998817 doi: 10.3389/fmicb.2022.998817
Comparative transcriptome analysis revealed molecular mechanisms of peanut leaves responding to Ralstonia solanacearum and its type III secretion system mutant.
Guangzhou Key Laboratory for Research and Development of Crop Germplasm Resources, Zhongkai University of Agriculture and Engineering, Guangzhou, China.; Key Laboratory of Horticultural Plant Biology (HZAU), Ministry of Education, Key Laboratory of Potato Biology and Biotechnology (HZAU), Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan, China.
Bacterial wilt caused by Ralstonia solanacearum is a serious soil-borne disease that limits peanut production and quality, but the molecular mechanisms of the peanut response to R. solanacearum remain unclear. In this study, we reported the first work analyzing the transcriptomic changes of the resistant and susceptible peanut leaves infected with R. solanacearum HA4-1 and its type III secretion system mutant strains by the cutting leaf method at different timepoints (0, 24, 36, and 72 h post inoculation). A total of 125,978 differentially expressed genes (DEGs) were identified and subsequently classified into six groups to analyze, including resistance-response genes, susceptibility-response genes, PAMPs induced resistance-response genes, PAMPs induced susceptibility-response genes, T3Es induced resistance-response genes, and T3Es induced susceptibility-response genes. KEGG enrichment analyses of these DEGs showed that plant-pathogen interaction, plant hormone signal transduction, and MAPK signaling pathway were the outstanding pathways. Further analysis revealed that CMLs/CDPKs-WRKY module, MEKK1-MKK2-MPK3 cascade, and auxin signaling played important roles in the peanut response to R. solanacearum. Upon R. solanacearum infection (RSI), three early molecular events were possibly induced in peanuts, including Ca(2+) activating CMLs/CDPKs-WRKY module to regulate the expression of resistance/susceptibility-related genes, auxin signaling was induced by AUX/IAA-ARF module to activate auxin-responsive genes that contribute to susceptibility, and MEKK1-MKK2-MPK3-WRKYs was activated by phosphorylation to induce the expression of resistance/susceptibility-related genes. Our research provides new ideas and abundant data resources to elucidate the molecular mechanism of the peanut response to R. solanacearum and to further improve the bacterial wilt resistance of peanuts.
PMID: 36090119
Biosensors (Basel) , IF:5.519 , 2022 Aug , V12 (9) doi: 10.3390/bios12090688
Functional Characterization and Phenotyping of Protoplasts on a Microfluidics-Based Flow Cytometry.
School of Environmental Science and Engineering, Tianjin University, Weijin Rd. 92, Tianjin 300072, China.; State Key Laboratory of Precision Measuring Technology and Instruments, College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Weijin Rd. 92, Tianjin 300072, China.
A better understanding of the phenotypic heterogeneity of protoplasts requires a comprehensive analysis of the morphological and metabolic characteristics of many individual cells. In this study, we developed a microfluidic flow cytometry with fluorescence sensor for functional characterization and phenotyping of protoplasts to allow an unbiased assessment of the influence of environmental factors at the single cell level. First, based on the measurement of intracellular homeostasis of reactive oxygen species (ROS) with a DCFH-DA dye, the effects of various external stress factors such as H2O2, temperature, ultraviolet (UV) light, and cadmium ions on intracellular ROS accumulation in Arabidopsis mesophyll protoplasts were quantitatively investigated. Second, a faster and stronger oxidative burst was observed in Petunia protoplasts isolated from white petals than in those isolated from purple petals, demonstrating the photoprotective role of anthocyanins. Third, using mutants with different endogenous auxin, we demonstrated the beneficial effect of auxin during the process of primary cell wall regeneration. Moreover, UV-B irradiation has a similar accelerating effect by increasing the intracellular auxin level, as shown by double fluorescence channels. In summary, our work has revealed previously underappreciated phenotypic variability within a protoplast population and demonstrated the advantages of a microfluidic flow cytometry for assessing the in vivo dynamics of plant metabolic and physiological indices at the single-cell level.
PMID: 36140072
iScience , IF:5.458 , 2022 Oct , V25 (10) : P105062 doi: 10.1016/j.isci.2022.105062
PIN-FORMED1 polarity in the plant shoot epidermis is insensitive to the polarity of neighboring cells.
School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia.; European Molecular Biology Laboratory, Heidelberg 69117, Germany.
At the Arabidopsis shoot apex, epidermal cells are planar-polarized along an axis marked by the asymmetric localization patterns of several proteins including PIN-FORMED1 (PIN1), which facilitates the directional efflux of the plant hormone auxin to pattern phyllotaxis. While PIN1 polarity is known to be regulated non-cell autonomously via the MONOPTEROS (MP) transcription factor, how this occurs has not been determined. Here, we use mosaic expression of the serine threonine kinase PINOID (PID) to test whether PIN1 polarizes according to the polarity of neighboring cells. Our findings reveal that PIN1 is insensitive to the polarity of PIN1 in neighboring cells arguing against auxin flux or extracellular auxin concentrations acting as a polarity cue, in contrast to previous model proposals.
PMID: 36157591
J Cell Sci , IF:5.285 , 2022 Oct , V135 (19) doi: 10.1242/jcs.260127
Defects in division plane positioning in the root meristematic zone affect cell organization in the differentiation zone.
Graduate Group in Biochemistry and Molecular Biology.; Department of Botany and Plant Sciences, Center for Plant Cell Biology, Institute of Integrative Genome Biology, University of California, Riverside, CA 92521, USA.
Cell-division-plane orientation is critical for plant and animal development and growth. TANGLED1 (TAN1) and AUXIN-INDUCED IN ROOT CULTURES 9 (AIR9) are division-site-localized microtubule-binding proteins required for division-plane positioning. The single mutants tan1 and air9 of Arabidopsis thaliana have minor or no noticeable phenotypes, but the tan1 air9 double mutant has synthetic phenotypes including stunted growth, misoriented divisions and aberrant cell-file rotation in the root differentiation zone. These data suggest that TAN1 plays a role in non-dividing cells. To determine whether TAN1 is required in elongating and differentiating cells in the tan1 air9 double mutant, we limited its expression to actively dividing cells using the G2/M-specific promoter of the syntaxin KNOLLE (pKN:TAN1-YFP). Unexpectedly, in addition to rescuing division-plane defects, expression of pKN:TAN1-YFP rescued root growth and cell file rotation defects in the root-differentiation zone in tan1 air9 double mutants. This suggests that defects that occur in the meristematic zone later affect the organization of elongating and differentiating cells.
PMID: 36074053
Biology (Basel) , IF:5.079 , 2022 Aug , V11 (8) doi: 10.3390/biology11081192
Application of 2,4-Epibrassinolide Improves Drought Tolerance in Tobacco through Physiological and Biochemical Mechanisms.
Key Laboratory of Tobacco Biology and Processing, Ministry of Agriculture and Rural Affairs, Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, China.; State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, 666 Wusu Street, Hangzhou 311300, China.; College of Life Science and Technology, Guangxi University, Nanning 530004, China.; Department of Agronomy, The University of Agriculture Peshawar, Peshawar 25130, Pakistan.
Drought stress is a major abiotic stress that hinders plant growth and development. Brassinosteroids (BR), including 2,4-epibrassinolide (EBR), play important roles in plant growth, development, and responses to abiotic stresses, including drought stress. This work investigates exogenous EBR application roles in improving drought tolerance in tobacco. Tobacco plants were divided into three groups: WW (well-watered), DS (drought stress), and DSB (drought stress + 0.05 mM EBR). The results revealed that DS decreased the leaf thickness (LT), whereas EBR application upregulated genes related to cell expansion, which were induced by the BR (DWF4, HERK2, and BZR1) and IAA (ARF9, ARF6, PIN1, SAUR19, and ABP1) signaling pathway. This promoted LT by 28%, increasing plant adaptation. Furthermore, EBR application improved SOD (22%), POD (11%), and CAT (5%) enzyme activities and their related genes expression (FeSOD, POD, and CAT) along with a higher accumulation of osmoregulatory substances such as proline (29%) and soluble sugars (14%) under DS and conferred drought tolerance. Finally, EBR application augmented the auxin (IAA) (21%) and brassinolide (131%) contents and upregulated genes related to drought tolerance induced by the BR (BRL3 and BZR2) and IAA (YUCCA6, SAUR32, and IAA26) signaling pathways. These results suggest that it could play an important role in improving mechanisms of drought tolerance in tobacco.
PMID: 36009819
Plant Cell Physiol , IF:4.927 , 2022 Sep doi: 10.1093/pcp/pcac126
The 5'-3' mRNA Decay Pathway Modulates The Plant Circadian Network In Arabidopsis.
Fundacion Instituto Leloir, Instituto de Investigaciones Bioquimicas de Buenos Aires-Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Buenos Aires, C1405BWE, Argentina.; Department of Biochemistry, University of Otago, Dunedin, 9016, New Zealand.
Circadian rhythms enable organisms to anticipate and adjust their physiology to periodic environmental changes. These rhythms are controlled by biological clocks that consist of a set of clock genes that regulate each other's expression. Circadian oscillations in mRNA levels require regulation of mRNA production and degradation. While transcription factors controlling clock function have been well characterised from cyanobacteria to humans, the role of factors controlling mRNA decay is largely unknown. Here, we show that mutations in LSM1 and XRN4, components of the 5'-3' mRNA decay pathway, alter clock function in Arabidopsis. We found that lsm1 and xrn4 mutants display long-period phenotypes for clock gene expression. In xrn4, these circadian defects were associated with changes in circadian phases of expression, but not overall mRNA levels, of several core clock genes. We then used non-invasive transcriptome-wide mRNA stability analysis to identify genes and pathways regulated by XRN4. Among genes affected in the xrn4 mutant at the transcriptional and post-transcriptional level, we found an enrichment in genes involved in auxin, ethylene, and drought recovery. Large effects were not observed for canonical core-clock genes, although the mRNAs of several auxiliary clock genes that control the pace of the clock, were stabilised in xrn4 mutants. Our results establish that the 5'-3' mRNA decay pathway constitutes a novel post-transcriptional regulatory layer of the circadian gene network, which probably acts through a combination of small effects on mRNA stability of several auxiliary and some core clock genes.
PMID: 36066193
Plant Cell Physiol , IF:4.927 , 2022 Sep , V63 (9) : P1309-1320 doi: 10.1093/pcp/pcac104
OsAMT1;1 and OsAMT1;2 Coordinate Root Morphological and Physiological Responses to Ammonium for Efficient Nitrogen Foraging in Rice.
Key Laboratory of Plant-Soil Interactions, MOE, College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian District, Beijing 100193, China.; State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, No. 866 Yuhangtang Road, Xihu District, Hangzhou City, Zhejiang Province 310058, China.
Optimal plant growth and development rely on morphological and physiological adaptions of the root system to forage heterogeneously distributed nitrogen (N) in soils. Rice grows mainly in the paddy soil where ammonium (NH4+) is present as the major N source. Although root NH4+ foraging behaviors are expected to be agronomically relevant, the underlying mechanism remains largely unknown. Here, we showed that NH4+ supply transiently enhanced the high-affinity NH4+ uptake and stimulated lateral root (LR) branching and elongation. These synergistic physiological and morphological responses were closely related to NH4+-induced expression of NH4+ transporters OsAMT1;1 and OsAMT1;2 in roots. The two independent double mutants (dko) defective in OsAMT1;1 and OsAMT1;2 failed to induce NH4+ uptake and stimulate LR formation, suggesting that OsAMT1s conferred the substrate-dependent root NH4+ foraging. In dko plants, NH4+ was unable to activate the expression of OsPIN2, and the OsPIN2 mutant (lra1) exhibited a strong reduction in NH4+-triggered LR branching, suggesting that the auxin pathway was likely involved in OsAMT1s-dependent LR branching. Importantly, OsAMT1s-dependent root NH4+ foraging behaviors facilitated rice growth and N acquisition under fluctuating NH4+ supply. These results revealed an essential role of OsAMT1s in synergizing root morphological and physiological processes, allowing for efficient root NH4+ foraging to optimize N capture under fluctuating N availabilities.
PMID: 35861152
Plant Cell Physiol , IF:4.927 , 2022 Aug , V63 (8) : P1038-1051 doi: 10.1093/pcp/pcac078
Root Cap to Soil Interface: A Driving Force Toward Plant Adaptation and Development.
Indian Institute of Science Education and Research (IISER) Tirupati, Biology Division, Tirupati, Andhra Pradesh 517507, India.
Land plants have developed robust roots to grow in diverse soil ecosystems. The distal end of the root tip has a specialized organ called the 'root cap'. The root cap assists the roots in penetrating the ground, absorbing water and minerals, avoiding heavy metals and regulating the rhizosphere microbiota. Furthermore, root-cap-derived auxin governs the lateral root patterning and directs root growth under varying soil conditions. The root cap formation is hypothesized as one of the key innovations during root evolution. Morphologically diversified root caps in early land plant lineage and later in angiosperms aid in improving the adaptation of roots and, thereby, plants in diverse soil environments. This review article presents a retrospective view of the root cap's important morphological and physiological characteristics for the root-soil interaction and their response toward various abiotic and biotic stimuli. Recent single-cell RNAseq data shed light on root cap cell-type-enriched genes. We compiled root cap cell-type-enriched genes from Arabidopsis, rice, maize and tomato and analyzed their transcription factor (TF) binding site enrichment. Further, the putative gene regulatory networks derived from root-cap-enriched genes and their TF regulators highlight the species-specific biological functions of root cap genes across the four plant species.
PMID: 35662353
Plant Cell Physiol , IF:4.927 , 2022 Aug , V63 (8) : P1029-1037 doi: 10.1093/pcp/pcac069
Seed Dormancy and Longevity: A Mutual Dependence or a Trade-Off?
School of Environment and Ecology, Northwestern Polytechnical University, No. 1, Dongxiang Road, Xi'an 710129, China.; Research and Development Institute of Northwestern Polytechnical University in Shenzhen, No. 45, Gaoxin South 9 Road, Shenzhen 518057, China.
Seed dormancy is an important agronomic trait in cereals and leguminous crops as low levels of seed dormancy during harvest season, coupled with high humidity, can cause preharvest sprouting. Seed longevity is another critical trait for commercial crop propagation and production, directly influencing seed germination and early seedling establishment. Both traits are precisely regulated by the integration of genetic and environmental cues. Despite the significance of these two traits in crop production, the relationship between them at the molecular level is still elusive, even with contradictory conclusions being reported. Some studies have proposed a positive correlation between seed dormancy and longevity in association with differences in seed coat permeability or seed reserve accumulation, whereas an increasing number of studies have highlighted a negative relationship, largely with respect to phytohormone-dependent pathways. In this review paper, we try to provide some insights into the interactions between regulatory mechanisms of genetic and environmental cues, which result in positive or negative relationships between seed dormancy and longevity. Finally, we conclude that further dissection of the molecular mechanism responsible for this apparently contradictory relationship between them is needed.
PMID: 35594901
Appl Microbiol Biotechnol , IF:4.813 , 2022 Sep doi: 10.1007/s00253-022-12194-5
In vitro production of atractylon and beta-eudesmol from Atractylodes chinensis by adventitious root culture.
Key Laboratory of Forest Plant Ecology, Ministry of Education, Heilongjiang Provincial Key Laboratory of Ecological Utilization of Forestry-Based Active Substances, College of Chemistry, Chemical Engineering and Resource Utilization, Northeast Forestry University, Harbin, 150040, China.; College of Forest Science, Kim Il Sung University, Pyongyang, 999093, Democratic People's Republic of Korea.; College of Life Science, Kim Il Sung University, Pyongyang, 999093, Democratic People's Republic of Korea.; Key Laboratory of Forest Plant Ecology, Ministry of Education, Heilongjiang Provincial Key Laboratory of Ecological Utilization of Forestry-Based Active Substances, College of Chemistry, Chemical Engineering and Resource Utilization, Northeast Forestry University, Harbin, 150040, China. wjwang225@hotmail.com.; Key Laboratory of Forest Plant Ecology, Ministry of Education, Heilongjiang Provincial Key Laboratory of Ecological Utilization of Forestry-Based Active Substances, College of Chemistry, Chemical Engineering and Resource Utilization, Northeast Forestry University, Harbin, 150040, China. whm0709@163.com.
Atractylodes chinensis is a medicinal plant widely used for the treatment of gastric disorders, and its main bioactive compounds are atractylon and beta-eudesmol. This study was purposed to establish the adventitious root culture system of A. chinensis for in vitro production of atractylon and beta-eudesmol. The main parameters in the adventitious root induction and suspension cultures were optimized to maximize the culture efficiency. Adventitious roots were induced most efficiently from leaf explants on Murashige and Skoog (MS) solid medium containing 1.5 mg/L naphthaleneacetic acid (NAA) and 30 g/L sucrose with the highest root induction rate of approximately 92% and 12.9 roots per explant. During the adventitious root suspension culture, the root biomass and the accumulated content of the target compounds simultaneously increased to reach the maximum values after 8 weeks of culture. The maximum yield of the target compounds (total concentration 3.38 mg/g DW, total yield 2.66 mg) was achieved in the roots cultured in (1/2) MS liquid medium supplemented with 2.0 mg/L IBA, 3.2 mg/L NAA, and 40 g/L sucrose with the inoculum density of 8 g/L. Through the central composite design experiment, it was found that the combined use of different types of auxins in the suspension culture could further improve root growth and metabolite accumulation than the application of only one type of auxin. This work provides a new possibility to have a promising candidate for the industrial production of A. chinensis pharmaceuticals without relying on wild resources or field cultivation. KEY POINTS: * The induction culture was optimized for efficient root induction. * Suspension culture was optimized for the atractylon and beta-eudesmol production. * Combined use of different auxins improves root growth and metabolite accumulation.
PMID: 36171502
Appl Environ Microbiol , IF:4.792 , 2022 Sep , V88 (18) : Pe0088222 doi: 10.1128/aem.00882-22
Elucidating the Effect of Endophytic Entomopathogenic Fungi on Bread Wheat Growth through Signaling of Immune Response-Related Hormones.
Department of Agronomy, ETSIAM, University of Cordoba, Cordoba, Spain.; Agroforestry and Plant Biochemistry, Proteomics and Systems Biology, Department of Biochemistry and Molecular Biology, University of Cordoba, UCO-CeiA3, Cordoba, Spain.; Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium.; Center of Plant Systems Biology, VIB, Ghent, Belgium.
Entomopathogenic fungi (EF) provide a potent biocontrol tool; also, their endophytic behavior has broadened their contribution to integrated pest management (IPM) and crop production. In this work, Beauveria bassiana and Metarhizium brunneum were applied to bread wheat (Triticum aestivum) seedlings to elucidate how fungal colonization influences plant growth and the relative expression of 24 genes involved in hormonal syntheses and plant immune mechanisms. A preliminary assay was used to determine the time needed for fungal colonization and assess its effect on wheat growth. Then, plant material collected at various times after inoculation (viz., 2, 8, 20, and 36 h and 9 and 15 days) was used to investigate gene expression by quantitative reverse transcription PCR (RT-qPCR). During the colonization time, B. bassiana and M. brunneum caused strong downregulation of most genes associated with plant immunity and the synthesis of hormones like auxin, cytokinin, and gibberellin. This effect was concomitant with a slowdown of endophytic-colonization-related plant growth until 19 days postinoculation (dpi). However, the wheat started to recover at 15 dpi, simultaneously with upregulation of auxin- and gibberellin-related genes. The results suggest that the EF trigger induced systemic resistance rather than acquired systemic resistance during early plant-microbe cross talk in wheat. Also, they confirm that the hormone and immune responses of wheat triggered by EF inoculation influenced plant growth, which can be useful with a view to optimizing management of these microorganisms for sustainable agriculture. IMPORTANCE Microbial control of insect and mite pests is a key tool to develop integrated pest management (IPM) and sustainable agriculture. Entomopathogenic fungi (EF) may have associations with the plants, playing additional ecological roles in the rhizosphere, in the phylloplane, and as plant endophytes. Beauveria bassiana 04/01TIP and Metarhizium brunneum 01/58Su are two strains that showed very good results either in pest control or plant growth promotion and would be good candidates to develop mycoinsecticides as an alternative to pesticides. However, deep knowledge about their interaction with the plant would let farmers optimize their use and understand the plant response, enhancing and promoting their broader contribution to IPM and crop production.
PMID: 36036583
Rice (N Y) , IF:4.783 , 2022 Aug , V15 (1) : P42 doi: 10.1186/s12284-022-00588-y
Salicylic Acid Acts Upstream of Auxin and Nitric Oxide (NO) in Cell Wall Phosphorus Remobilization in Phosphorus Deficient Rice.
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science, Nanjing, 210008, China.; University of Chinese Academy of Sciences, Beijing, 100049, China.; Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, 1138657, Japan.; State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science, Nanjing, 210008, China. xiaofangzhu@issas.ac.cn.; University of Chinese Academy of Sciences, Beijing, 100049, China. xiaofangzhu@issas.ac.cn.
Salicylic acid (SA) is thought to be involved in phosphorus (P) stress response in plants, but the underlying molecular mechanisms are poorly understood. Here, we showed that P deficiency significantly increased the endogenous SA content by inducing the SA synthesis pathway, especially for up-regulating the expression of PAL3. Furthermore, rice SA synthetic mutants pal3 exhibited the decreased root and shoot soluble P content, indicating that SA is involved in P homeostasis in plants. Subsequently, application of exogenous SA could increase the root and shoot soluble P content through regulating the root and shoot cell wall P reutilization. In addition, - P + SA treatment highly upregulated the expression of P transporters such as OsPT2 and OsPT6, together with the increased xylem P content, suggesting that SA also participates in the translocation of the P from the root to the shoot. Moreover, both signal molecular nitric oxide (NO) and auxin (IAA) production were enhanced when SA is applied while the addition of respective inhibitor c-PTIO (NO scavenger) and NPA (IAA transport inhibitor) significantly decreased the root and shoot cell wall P remobilization in response to P starvation. Taken together, here SA-IAA-NO-cell wall P reutilization pathway has been discovered in P-starved rice.
PMID: 35920901
J Chromatogr A , IF:4.759 , 2022 Sep , V1682 : P463497 doi: 10.1016/j.chroma.2022.463497
Quantification of six types of cytokinins: Integration of an ultra-performance liquid chromatographic-electrospray tandem mass spectrometric method with antibody based immunoaffinity columns equally recognizing cytokinins in free base and nucleoside forms.
College of Agronomy, China Agricultural University, Beijing 100193, People's Republic of China.; Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo 315211, People's Republic of China.; College of Agronomy, China Agricultural University, Beijing 100193, People's Republic of China. Electronic address: yangxiaolin429@cau.edu.cn.; College of Agronomy, China Agricultural University, Beijing 100193, People's Republic of China. Electronic address: wbaomin@263.net.
Cytokinins (CTKs) exist in various types in plants. The accurate quantification of free base and nucleoside types of cytokinins are helpful for better understanding their physiological role. In the present study, antibodies against trans-zeatin riboside (tZR) and N(6)-isopentenyladenine riboside (iPR) antibodies with equal recognition to free base and nucleoside cytokinins were developed. The cross-reactivity of tZR mAb 3G101G7 with tZR, trans-zeatin (tZ), dihydrozeatin riboside (DHZR), dihydrozeatin (DHZ), iPR, and N(6)-isopentenyladenine (iP) was 100.0%, 95.7%, 19.1%, 18.0%, 1.1%, and 0.7%, and that of iPR mAb 5C82F1 with above-mentioned 6 types of cytokinins was 1.5%, 1.4%, 5.7%, 3.1%, 100.0% and 92.6%, respectively. The obtained antibodies were used to prepare two immunoaffinity columns (IAC). The elution efficiencies of tZR 3G101G7-IAC for tZ and tZR, DHZ and DHZR and of iPR 5C82F1-IAC for iP and iPR were almost no difference with the same loading amount on their corresponding IACs. Subsequently, six types of cytokinins in mepiquat chloride (MC)-treated cotton (Gossypium hirsutum L.) roots were determined by IACs combined with ultra-performance liquid chromatography-electrospray tandem mass spectrometry (UPLC-ESI-MS/MS). The contents of tZR, iPR and DHZR were increased by 9.3 approximately 38.5%, 6.6 approximately 23.5%, and 30.1 approximately 110.0%, respectively, whereas those of tZ and iP were reduced by 5.3 approximately 20.0% and 27.7 approximately 32.1%, respectively. The decreased tZ and iP levels led to the ratio of auxin-to-active cytokinins increase to promote lateral root initiation in MC-treated cotton seeding. Integration of the IACs equally recognizing cytokinins in their free base and nucleoside forms with UPLC-ESI-MS/MS can accurately quantify different cytokinins in plant tissues.
PMID: 36166882
Plant Sci , IF:4.729 , 2022 Sep , V325 : P111462 doi: 10.1016/j.plantsci.2022.111462
Overexpression of SmLAC25 promotes lignin accumulation and decreases salvianolic acid content in Salvia miltiorrhiza.
Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, College of Life Science, Shaanxi Normal University, Xi'an 710062, China.; College of Life Science and Food Engineering, Shaanxi Xueqian Normal University, Xi'an 710100, China.; Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, College of Life Science, Shaanxi Normal University, Xi'an 710062, China. Electronic address: Zhuxj2018@snnu.edu.cn.; Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, College of Life Science, Shaanxi Normal University, Xi'an 710062, China. Electronic address: caoxiaoyan@snnu.edu.cn.
Laccase (LAC) is a blue multicopper oxidase that contains four copper ions, which is involved in lignin polymerization and flavonoid biosynthesis in plants. Although dozens of LAC genes have been identified in Salvia miltiorrhiza Bunge (a model medicinal plant), most have not been functionally characterized. Here, we explored the expression patterns and the functionality of SmLAC25 in S. miltiorrhiza. SmLAC25 has a higher expression level in roots and responds to methyl jasmonate, auxin, abscisic acid, and gibberellin stimuli. The SmLAC25 protein is localized in the cytoplasm and chloroplasts. Recombinant SmLAC25 protein could oxidize coniferyl alcohol and sinapyl alcohol, two monomers of G-lignin and S-lignin. To investigate its function, we generated SmLAC25-overexpressed S. miltiorrhiza plantlets and hairy roots. The lignin content increased significantly in all SmLAC25-overexpressed plantlets and hairy roots, compared with the controls. However, the concentrations of rosmarinic acid and salvianolic acid B decreased significantly in all the SmLAC25-overexpressed lines. Further studies revealed that the transcription levels of some key enzyme genes in the lignin synthesis pathway (e.g., SmCCR and SmCOMT) were significantly improved in the SmLAC25-overexpressed lines, while the expression levels of multiple enzyme genes in the salvianolic acid biosynthesis pathway were inhibited. We speculated that the overexpression of SmLAC25 promoted the metabolic flux of lignin synthesis, which resulted in a decreased metabolic flux to the salvianolic acid biosynthesis pathway.
PMID: 36126879
Plant Sci , IF:4.729 , 2022 Sep , V325 : P111461 doi: 10.1016/j.plantsci.2022.111461
Dissection of transcriptome and metabolome insights into the isoquinoline alkaloid biosynthesis during stem development in Phellodendron amurense (Rupr.).
Jilin Provincial Key Laboratory of Tree and Grass Genetics and Breeding, College of Forestry and Grassland Science, Jilin Agricultural University, Changchun 130118, China; State Key Laboratory of Tree Genetics and Breeding, School of Forestry, Northeast Forestry University, Harbin 15004, China. Electronic address: lx2016bjfu@163.com.; State Key Laboratory of Tree Genetics and Breeding, School of Forestry, Northeast Forestry University, Harbin 15004, China. Electronic address: ckwnefu@163.com.; Linjiang Forestry Bureau of Jilin Province, Linjiang 134600, China. Electronic address: 38047646@qq.com.; Linjiang Forestry Bureau of Jilin Province, Linjiang 134600, China. Electronic address: 67651509@qq.com.; Linjiang Forestry Bureau of Jilin Province, Linjiang 134600, China. Electronic address: 18314591710@163.com.; Linjiang Forestry Bureau of Jilin Province, Linjiang 134600, China. Electronic address: 893483624@qq.com.; Linjiang Forestry Bureau of Jilin Province, Linjiang 134600, China. Electronic address: 1604861006@qq.com.; Jilin Provincial Key Laboratory of Tree and Grass Genetics and Breeding, College of Forestry and Grassland Science, Jilin Agricultural University, Changchun 130118, China. Electronic address: xiaonapei2020@163.com.; Jilin Provincial Key Laboratory of Tree and Grass Genetics and Breeding, College of Forestry and Grassland Science, Jilin Agricultural University, Changchun 130118, China; State Key Laboratory of Tree Genetics and Breeding, School of Forestry, Northeast Forestry University, Harbin 15004, China. Electronic address: zhaoxyphd@163.com.
Phellodendron amurense (Rupr.) is a well-known medicinal plant with high medicinal value, and its various tissues are enriched in various active pharmaceutical ingredients. Isoquinoline alkaloids are the primary medicinal component of P. amurense and have multiple effects, such as anti-inflammation, antihypertension, and antitumor effects. However, the potential regulatory mechanism of isoquinoline alkaloid biosynthesis during stem development in P. amurense is still poorly understood. In the present study, a total of eight plant hormones for each stem development stage were detected; of those, auxin, gibberellins and brassinosteroids were significantly highly increased in perennial stems and played key roles during stem development in P. amurense. We also investigated the content and change pattern of secondary metabolites and comprehensively identified some key structural genes involved in the isoquinoline alkaloid biosynthesis pathway by combining the transcriptome and metabolomics. A total of 39,978 DEGs were identified in the present study, and six of those had candidate structural genes (NCS, GOT2, TYNA, CODM, TYR, TAT and PSOMT1) that were specifically related to isoquinoline alkaloid biosynthesis in P. amurense. Corydalmine, cyclanoline, dehydroyanhunine, (S)-canadine and corybulbine were the most significantly upregulated metabolites among the different comparative groups. Three differentially expressed metabolites, dopamine, (S)-corytuberine and (S)-canadine, were enriched in the isoquinoline alkaloid biosynthesis pathway. Furthermore, bHLH and WRKY transcription factors play key roles in the isoquinoline alkaloid biosynthesis pathway in P. amurense. The results not only provide comprehensive genetic information for understanding the molecular mechanisms of isoquinoline alkaloid biosynthesis but also lay a foundation for the combinatory usage of the medicinal active ingredient of P. amurense.
PMID: 36122814
Plant Sci , IF:4.729 , 2022 Sep , V325 : P111459 doi: 10.1016/j.plantsci.2022.111459
ZmDWF1 regulates leaf angle in maize.
State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, China.; College of Agronomy, National Key Laboratory of Wheat and Maize Crop Science and Key Laboratory of Regulating and Controlling Crop Growth and Development Ministry of Education, Henan Agricultural University, No. 15 Longzihu University Park, Zhengdong New Area, Zhengzhou, Henan 450046, China; Henan Academy of Agricultural Science, Zhengzhou, Henan 450002, China.; College of Agronomy, National Key Laboratory of Wheat and Maize Crop Science and Key Laboratory of Regulating and Controlling Crop Growth and Development Ministry of Education, Henan Agricultural University, No. 15 Longzihu University Park, Zhengdong New Area, Zhengzhou, Henan 450046, China.; College of Agronomy, National Key Laboratory of Wheat and Maize Crop Science and Key Laboratory of Regulating and Controlling Crop Growth and Development Ministry of Education, Henan Agricultural University, No. 15 Longzihu University Park, Zhengdong New Area, Zhengzhou, Henan 450046, China. Electronic address: kulixia0371@163.com.
Leaf angle (LA) is a critical agronomic trait enhancing grain yield under high-density planting in maize. A number of researches have been conducted in recent years to investigate the quantitative trait loci/genes responsible for LA variation, while only a few genes were identified through map-based cloning. Here we cloned the ZmDWF1 gene, which was previously reported to encode Delta24-sterol reductase in the brassinosteroids (BRs) biosynthesis pathway. Overexpression of ZmDWF1 resulted in enlarged LA, indicating that ZmDWF1 is a positive regulator of LA in maize. To reveal the regulatory framework of ZmDWF1, we conducted RNA-Sequencing and yeast-two hybrid (Y2H) screening analysis. RNA-Sequencing analyzing results indicate ZmDWF1 mainly affected expression level of genes involved in cell wall associated metabolism and hormone metabolism including BR, gibberellin, and auxin. Y2H screening with Bi-FC assay confirmed three proteins (ZmPP2C-1, ZmROF1, and ZmTWD1) interacting with ZmDWF1. We revealed a new regulatory network of ZmDWF1 gene in controlling plant architecture in maize.
PMID: 36113675
Plant Sci , IF:4.729 , 2022 Sep , V325 : P111456 doi: 10.1016/j.plantsci.2022.111456
The cytokinin type-B response regulator PeRR12 is a negative regulator of adventitious rooting and salt tolerance in poplar.
Co-Innovation Center for Sustainable Forestry in Southern China, Key Laboratory of Forest Genetics and Biotechnology Ministry of Education, Nanjing Forestry University, Nanjing 210037, China. Electronic address: HaoranQi@njfu.edu.cn.; Co-Innovation Center for Sustainable Forestry in Southern China, Key Laboratory of Forest Genetics and Biotechnology Ministry of Education, Nanjing Forestry University, Nanjing 210037, China; Institute of Pomology, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China. Electronic address: hengcai@njfu.edu.cn.; Co-Innovation Center for Sustainable Forestry in Southern China, Key Laboratory of Forest Genetics and Biotechnology Ministry of Education, Nanjing Forestry University, Nanjing 210037, China. Electronic address: chicta@163.com.; Co-Innovation Center for Sustainable Forestry in Southern China, Key Laboratory of Forest Genetics and Biotechnology Ministry of Education, Nanjing Forestry University, Nanjing 210037, China. Electronic address: sianliu@yzu.edu.cn.; State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China. Electronic address: changjunding@caf.ac.cn.; Co-Innovation Center for Sustainable Forestry in Southern China, Key Laboratory of Forest Genetics and Biotechnology Ministry of Education, Nanjing Forestry University, Nanjing 210037, China. Electronic address: xum@njfu.edu.cn.
Adventitious root (AR) development is an ecologically and economically important biological process that maintains ecological balance, improves plant survivability, and allows for massive vegetative propagation, but its genetic mechanisms are not well understood. Here, eight Arabidopsis response regulator (ARR) genes were cloned and identified in poplar, most of which were detected in the AR, phloem, and xylem and showed remarkable induction at different time points during AR development. Subcellular localization indicated that most of these PeRR genes are in the nucleus. Based on qRT-PCR expression analysis of some genes related to AR development, we inferred that overexpression of PeRR12 (OE_PeRR12) may inhibited AR formation by suppressing the transcription of PeWOX11, PeWOX5, PePIN1 and PePIN3 in poplar while promoting type-A RR transcripts. Correspondingly, exogenous auxin partially restored the rooting of OE_PeRR12 poplar by inhibiting PeRR12 expression. Moreover, the activities of the antioxidant systems of OE_PeRR12 poplars were lower than those of wild-type poplars under salt stress conditions, indicating that PeRR12 may acts as a repressor that mediates salt tolerance by suppressing the expression of PeHKT1;1. Altogether, these results suggest that PeRR12 plays essential roles in mediating AR formation and salinity tolerance in poplar.
PMID: 36087886
Plant Sci , IF:4.729 , 2022 Nov , V324 : P111421 doi: 10.1016/j.plantsci.2022.111421
AtHB40 modulates primary root length and gravitropism involving CYCLINB and auxin transporters.
Instituto de Agrobiotecnologia del Litoral (CONICET, Universidad Nacional del Litoral, FBCB), Colectora Ruta Nacional 168, km 0, 3000 Santa Fe, Argentina.; Centro Nacional de Biotecnologia (CNB) - CSIC, Madrid, Spain.; Instituto de Agrobiotecnologia del Litoral (CONICET, Universidad Nacional del Litoral, FBCB), Colectora Ruta Nacional 168, km 0, 3000 Santa Fe, Argentina. Electronic address: rchan@fbcb.unl.edu.ar.
Gravitropism is a finely regulated tropistic response based on the plant perception of directional cues. Such perception allows them to direct shoot growth upwards, above ground, and root growth downwards, into the soil, anchoring the plant to acquire water and nutrients. Gravity sensing occurs in specialized cells and depends on auxin distribution, regulated by influx/efflux carriers. Here we report that AtHB40, encoding a transcription factor of the homeodomain-leucine zipper I family, was expressed in the columella and the root tip. Athb40 mutants exhibited longer primary roots. Enhanced primary root elongation was in agreement with a higher number of cells in the transition zone and the induction of CYCLINB transcript levels. Moreover, athb40 mutants and AtHB40 overexpressors displayed enhanced and delayed gravitropistic responses, respectively. These phenotypes were associated with altered auxin distribution and deregulated expression of the auxin transporters LAX2, LAX3, and PIN2. Accordingly, lax2 and lax3 mutants also showed an altered gravitropistic response, and LAX3 was identified as a direct target of AtHB40. Furthermore, AtHB40 is induced by AtHB53 when the latter is upregulated by auxin. Altogether, these results indicate that AtHB40 modulates cell division and auxin distribution in the root tip thus altering primary root length and gravitropism.
PMID: 35995111
Plant Sci , IF:4.729 , 2022 Oct , V323 : P111415 doi: 10.1016/j.plantsci.2022.111415
IbTLD modulates reactive oxygen species scavenging and DNA protection to confer salinity stress tolerance in tobacco.
Agricultural Biotechnology Research Center, Academia Sinica, Taipei 11529, Taiwan. Electronic address: tcch@ucdavis.edu.; Department of Life Sciences, National Chung Hsing University, Taichung 40227, Taiwan. Electronic address: abslwert@gmail.com.; Department of Life Sciences, National Chung Hsing University, Taichung 40227, Taiwan. Electronic address: r98b43022@gmail.com.; Department of Life Sciences, National Chung Hsing University, Taichung 40227, Taiwan. Electronic address: jslin@dragon.nchu.edu.tw.
Plants accumulate reactive oxygen species (ROS) that may damage the cells under prolonged stress conditions. Reduction of the excessive ROS production can alleviate oxidative damage and enhance the survival rates under stress. TLDc-containing protein (TLD) was reported to confer tolerance to oxidative stress, but the regulatory mechanism of TLD remains unclear. In this study, we ectopically overexpressed the Ipomoea batatas TLDc gene (IbTLD) in tobacco and characterized its functions. RNA-sequencing analysis and Gene Ontology term enrichment analysis revealed that IbTLD up-regulates auxin-responsive genes in response to oxidative stress. Under salinity stress, the IbTLD transgenic lines showed higher germination rates, chlorophyll contents, and root lengths than wild type (W38). In addition, the IbTLD transgenic lines showed higher expression of ROS scavenging genes, nudix hydrolases, ROS scavenging enzyme activity, and lesser DNA damage compared to W38 under salinity stress. Therefore, our results suggest that IbTLD activates the expression of ROS scavenging genes and confers tolerance to salinity stress in planta.
PMID: 35963494
Plant Sci , IF:4.729 , 2022 Oct , V323 : P111409 doi: 10.1016/j.plantsci.2022.111409
PpPIF8, a DELLA2-interacting protein, regulates peach shoot elongation possibly through auxin signaling.
College of Horticulture, Henan Agricultural University, 95 Wenhua Road, Zhengzhou 450002, China.; College of Horticulture, Henan Agricultural University, 95 Wenhua Road, Zhengzhou 450002, China. Electronic address: jcheng2007@163.com.; College of Horticulture, Henan Agricultural University, 95 Wenhua Road, Zhengzhou 450002, China. Electronic address: jcfeng@henau.edu.cn.
Rapid growth of branches in a peach tree restricts the light penetration and air ventilation within the orchard, which lowers fruit quality and promotes the occurrence of diseases and insects. Our previous works showed that PpDELLA1 and PpDELLA2 repress the rapid growth of annual shoots. Proteins that interact with DELLA are vital for its function. In this study, seven PpPIFs (PpPIF1, -2, -3, -4, -6, -7 and -8) were identified in the peach genome and contain a conserved bHLH domain. Among the seven PpPIFs, PpPIF8 interacted with PpDELLA2 through an unknown motif in the C-terminal and/or the bHLH domain. Overexpression of PpPIF8 in Arabidopsis promotes plant height and branch numbers. Hypocotyl elongation was significantly enhanced by PpPIF8 under weak light intensity. PpPIF8 overexpressed in Arabidopsis and transiently expressed in peach seedlings upregulated the transcription of YUCCA and SAUR19 and downregulated SHY1 and -2. Additionally, PpPIF4 and -8 were significantly induced by weak light. Phylogentic analysis and intron patterns of the bHLH domain strongly suggested that PIFs from six species could be divided into two groups of different evolutionary origins. These results lay a foundation for the further study of the repression of shoot growth by PpDELLA2 through protein interaction with PpPIF8 in peach.
PMID: 35934255
Plant Sci , IF:4.729 , 2022 Oct , V323 : P111408 doi: 10.1016/j.plantsci.2022.111408
Overexpression of a SHORT-ROOT transcriptional factor enhances the auxin mediated formation of adventitious roots and lateral roots in poplar trees.
School of Environmental Science and Engineering, Tianjin University, Weijin Rd. 92, Nankai District, Tianjin 300072, China.. Electronic address: 2441909790@qq.com.; School of Environmental Science and Engineering, Tianjin University, Weijin Rd. 92, Nankai District, Tianjin 300072, China.. Electronic address: 1501661988@qq.com.; School of Environmental Science and Engineering, Tianjin University, Weijin Rd. 92, Nankai District, Tianjin 300072, China.. Electronic address: 18700944808@163.com.; School of Environmental Science and Engineering, Tianjin University, Weijin Rd. 92, Nankai District, Tianjin 300072, China.. Electronic address: shaohuiyang77@tju.edu.cn.; School of Environmental Science and Engineering, Tianjin University, Weijin Rd. 92, Nankai District, Tianjin 300072, China.. Electronic address: jiehuawang@tju.edu.cn.
SHORT-ROOT (SHR) defines root stem cells and maintains radial patterning, but its involvement in adventitious root (AR) formation has not been reported. In this study, we showed that PtSHR2 was transcriptionally upregulated by excision before the formation of AR and responded dynamically to auxin. PtSHR2 overexpression (SHR2B(OE)) in hybrid poplars resulted in an increased number of ARs with an initial delay. Despite a lower endogenous content in the stems than in wild-type plants, indole-3-acetic acid (IAA) content at the SHR2B(OE) basal stem increased rapidly after cutting and reached a higher maximum than in wild-type plants, which was accompanied by a more sustained and stronger induction of AR formation marker genes. In addition, the higher auxin content in SHR2B(OE) ARs resulted in more and longer lateral roots (LRs). Application of auxin abolished the early delay in the formation of AR and largely other AR phenotypes of SHR2B(OE) plants, whereas the polar auxin transport inhibitor N-1-naphthylphthalamic acid completely inhibited both AR and LR abnormalities. Since the enhanced rooting ability of SHR2B(OE) stem cuttings in hydroponics was clearly confirmed, our results suggest a novel role of poplar SHR2 as a positive regulator during the organogenesis of AR and LR by affecting local auxin homeostasis.
PMID: 35932828
Plant Sci , IF:4.729 , 2022 Sep , V322 : P111371 doi: 10.1016/j.plantsci.2022.111371
Auxin facilitates cell wall phosphorus reutilization in a nitric oxide-ethylene dependent manner in phosphorus deficient rice (Oryza sativa L.).
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China.; State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Science, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: xiaofangzhu@issas.ac.cn.
Auxin is involved in stress responses of plants, such as phosphorus (P) deficiency in rice. Studies on whether auxin participates in cell-wall inorganic phosphorous (Pi) reutilization in Pi-starved rice are scarce. This study explored the mechanisms underlying auxin-facilitated cell-wall Pi-reutilization in rice roots. Pi deficiency rapidly induced auxin accumulation in roots; exogenous auxin [alpha-naphthaleneacetic acid (NAA), a permeable analog of auxin] elevated soluble Pi content in roots and shoots by increasing pectin content by enhancing activity of pectin methylesterase, and upregulating the transcript level of PHOSPHORUS-TRANSPORTER-2, such that more Pi was translocated to the shoot. Irrespective of the Pi status, exogenous auxin induced nitric oxide (NO) and ethylene production, while exogenous sodium nitroprusside (an NO donor) and 1-aminocyclopropane-1-carboxylic acid (a precursor of ethylene) had no effect on auxin content, suggesting that auxin may act upstream of NO and ethylene. The beneficial effect of NAA in increasing soluble Pi content in roots and shoots disappeared when 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (a scavenger of NO) or aminoethoxyvinylglycine (an inhibitor of ethylene) were applied, suggesting that auxin facilitates cell-wall Pi-reutilization in a NO-ethylene-dependent manner in Pi-deficient rice. Our study results suggest auxin application as an effective agronomic practice for improving plant Pi nutrition in P-deficient conditions.
PMID: 35809682
Plant Sci , IF:4.729 , 2022 Sep , V322 : P111366 doi: 10.1016/j.plantsci.2022.111366
A MADS-box transcription factor, SlMADS1, interacts with SlMACROCALYX to regulate tomato sepal growth.
Laboratory of Fruit Biology, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing 100083, China; Key Laboratory of Plant Resources, Institute of Botany, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing 100093, China.; Laboratory of Fruit Biology, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing 100083, China.; Laboratory of Fruit Quality Biology/Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou 310058, China; Plant Sciences Division, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD UK.; Laboratory of Fruit Biology, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing 100083, China. Electronic address: daqifu@cau.edu.cn.
In flowering plants, sepals play important roles in the development of flowers and fruit, and both processes are regulated by MADS-box (MADS) transcription factors (TFs). SlMADS1 was previously reported to act as a negative regulator of fruit ripening. In this study, expression analysis shown that its transcripts were very highly expressed during the development of sepals. To test the role of SlMADS1, we generated KO-SlMADS1 (knock-out) tomato mutants by CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats and CRISPR-associated protein 9) technology and over-expression of SlMADS1 (OE-SlMADS1). The sepals and individual cells of KO-SlMADS1 mutants were significantly elongated, compared with the wild type (WT), whereas the sepals of OE-SlMADS1 tomatoes were significantly shorter and their cells were wider. RNA-seq (RNA-sequencing) of sepal samples showed that ethylene-, gibberellin-, auxin-, cytokinin- and cell wall metabolism-related genes were significantly affected in both KO-SlMADS1 and OE-SlMADS1 plants with altered sepal size. Since SlMACROCALYX (MC) is known to regulate the development of tomato sepals, we also studied the relationship between SlMC and SlMADS1 and the result showed that SlMADS1 interacts directly with SlMC. In addition, we also found that manipulating SlMADS1 expression alters the development of tomato plant leaves, roots and plant height. These results enrich our understanding of sepal development and the function of SlMADS1 throughout the plant.
PMID: 35779674
Plant Sci , IF:4.729 , 2022 Sep , V322 : P111349 doi: 10.1016/j.plantsci.2022.111349
The carbohydrate elicitor Riclinoctaose facilitates defense and growth of potato roots by inducing changes in transcriptional and metabolic profiles.
Center for Molecular Metabolism, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Nanjing 210094, China.; Center for Molecular Metabolism, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Nanjing 210094, China; School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Nanjing 210094, China.; Center for Molecular Metabolism, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Nanjing 210094, China; School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Nanjing 210094, China. Electronic address: jingli.seb@njust.edu.cn.
Promoting both root growth and defense is conducive to the production of potatoes (Solanum tuberosum L.), while the role of elicitors in this topic hasn't been fully understood. To investigate the effect of Riclinoctaose (RiOc) on root growth and defense, potato tissue cuttings were cultivated with different concentration of RiOc (0, 50, 200 mg/L) for 5 weeks and changes in root morphology, transcription, enzymatic and metabolomic profiles were monitored over time. The results indicated that RiOc triggered the salicylic acid (SA)-mediated defense response and facilitated the growth of adventitious and lateral roots in a dose- and time-dependent manner. MPK3/MPK6, SA- and auxin-signaling pathways and transcription factors such as WUS, SCR and GRAS4/GRAS9 participated in this process. Moreover, the (1)H NMR based metabolome profiling demonstrated that potato roots altered the primary metabolism to respond to the RiOc elicitation and efficiency in production and allocation of defense and growth-related metabolites was improved. After 5-week treatment, the level of glucose, N-acetylglucosamine, glutamine, asparagine, isoleucine, valine, 3-hydroxyisovalerate and ferulate increased, while acetate, acetoacetate, fucose, and 2-hydroxyphenylacetate declined. In conclusion, RiOc played dual roles in activating the SA-mediated defense response and in promoting growth of potato roots by inducing changes in root transcription and metabolism.
PMID: 35709981
Front Genet , IF:4.599 , 2022 , V13 : P960027 doi: 10.3389/fgene.2022.960027
Integrated transcriptome and hormone analyses provide insights into silver thiosulfate-induced "maleness" responses in the floral sex differentiation of pumpkin (Cucurbita moschata D.).
College of Horticulture and Landscape, Henan Institute of Science and Technology, Xinxiang, China.; Henan Province Engineering Research Center of Horticultural Plant Resource Utilization and Germplasm Enhancement, Xinxiang, China.
The perfect mating of male and female flowers is the key to successful pollination. The regulation of ethylene with chemicals is a good option for inducing staminate or female flowers. Silver thiosulfate is often used to induce the formation of male flowers in subgynoecious and gynoecious crops, which is important to maintain their progenies. However, its effects on flower sex differentiation in pumpkin (Cucurbita moschata Duch.) and the underlying mechanism remain unclear. In this study, the application of silver thiosulfate to pumpkin seedlings significantly delayed the occurrence of the first female flower and increased the number of male flowers. We next investigated the underlying mechanism by employing transcriptome and endogenous hormone analyses of the treated plants. In total, 1,304 annotated differentially expressed genes (DEGs)were identified by comparing silver thiosulfate-treated and control plants. Among these genes, 835 were upregulated and 469 were downregulated. The DEGs were mainly enriched in the phenylpropanoid biosynthesis and metabolism pathways (phenylalanine ammonia-lyase, peroxidase) and plant hormone signal transduction pathways (auxin signaling, indole-3-acetic acid-amido synthetase, ethylene response factor). Silver thiosulfate significantly reduced the levels of 2-oxindole-3-acetic acid, para-topolin riboside, dihydrozeatin-O-glucoside riboside, and jasmonoyl-l-isoleucine but increased the levels of trans-zeatin-O-glucoside, cis-zeatin riboside, and salicylic acid 2-O-beta-glucoside. The levels of auxin and jasmonic acid were decreased, whereas those of salicylic acid were increased. Different trends were observed for different types of cytokinins. We concluded that silver thiosulfate treatment not only affects the expression of auxin synthesis and signaling genes but also that of ethylene response factor genes and regulates the levels of auxin, salicylic acid, jasmonic acid, and cytokinins, which together might contribute to the maleness of pumpkin. This study provides useful information for understanding the mechanism underlying the effect of silver thiosulfate on floral sex differentiation in pumpkin, a widely cultivated vegetable crop worldwide, and gives a production guidance for the induction of maleness using STS for the reproduction of gynoecious lines of Cucurbitaceae crops.
PMID: 36105109
Front Genet , IF:4.599 , 2022 , V13 : P957360 doi: 10.3389/fgene.2022.957360
Cross-talk between the cytokinin, auxin, and gibberellin regulatory networks in determining parthenocarpy in cucumber.
Division of Vegetable Science, ICAR-Indian Agricultural Research Institute, New Delhi, India.; Division of Agricultural Chemicals, ICAR-Indian Agricultural Research Institute, New Delhi, India.; Division of Plant Physiology, ICAR-Indian Agricultural Research Institute, New Delhi, India.; Division of Genetics, ICAR-Indian Agricultural Statistics Research Institute, New Delhi, India.; Centre for Agricultural Bioinformatics, ICAR-Indian Agricultural Statistics Research Institute, New Delhi, India.; ICAR-Indian Institute of Vegetable Research, Varanasi, India.
Cucumber is a model plant for studying parthenocarpy with abundant slicing- and pickling-type germplasm. This study was undertaken to understand the role of the important cytokines (CKs), auxin (AUX) and gibberellin (GA) biosynthesis and degradation genes for the induction of parthenocarpy in slicing and pickling germplasm. Two genotypes of gynoecious parthenocarpic cucumber, PPC-6 and DG-8, along with an MABC-derived gynoecious non-parthenocarpic line, IMPU-1, were evaluated in this study. The slicing and pickling cucumber genotypes PPC-6 and DG-8 were strongly parthenocarpic in nature and set fruit normally without pollination. Endogenous auxin and gibberellin were significantly higher in parthenocarpic than non-parthenocarpic genotypes, whereas the concentration of cytokinins varied among the genotypes at different developmental stages. However, the exogenous application of Zeatin and IAA + Zeatin was effective in inducing parthenocarpic fruit in IMPU-1. Expression analysis with important CK, AUX, and GA biosynthesis-related genes was conducted in IMPU-1, PPC-6, and DG-8. The expression of the CK synthase, IPT, IPT3, PaO, LOG1, LOG2, CYP735A1, and CYP735A2 was up-regulated in the parthenocarpic genotypes. Among the transcription factor response regulators (RRs), positive regulation of CSRR8/9b, CSRR8/9d, CSRR8/9e, and CSRR16/17 and negative feedback of the CK signalling genes, such as CsRR3/4a, CsRR3/4b, CsRR8/9a, and CsRR8/9c, were recorded in the parthenocarpic lines. Homeostasis between cytokinin biosynthesis and degradation genes such as CK oxidases (CKXs) and CK dehydrogenase resulted in a non-significant difference in the endogenous CK concentration in the parthenocarpic and non-parthenocarpic genotypes. In addition, up-regulation of the key auxin-inducing proteins and GA biosynthesis genes indicated their crucial role in the parthenocarpic fruit set of cucumber. This study establishes the critical role of the CKs, AUX, and GA regulatory networks and their cross-talk in determining parthenocarpy in slicing and pickling cucumber genotypes.
PMID: 36092914
Front Genet , IF:4.599 , 2022 , V13 : P931659 doi: 10.3389/fgene.2022.931659
Genome-Wide Analysis and Evolutionary Perspective of the Cytokinin Dehydrogenase Gene Family in Wheat (Triticum aestivum L.).
Centre for Agricultural Bioinformatics, ICAR-Indian Agricultural Statistics Research Institute, New Delhi, India.; ICAR-National Bureau of Plant Genetic Resources, New Delhi, India.; Department of Biotechnology, School of Interdisciplinary and Allied Sciences (SIAS), Central University of Haryana, Haryana, India.
Cytokinin dehydrogenase (CKX; EC.1.5.99.12) regulates the level of cytokinin (CK) in plants and is involved in CK regulatory activities. In different plants, a small gene family encodes CKX proteins with varied numbers of members. These genes are expanded in the genome mainly due to segmental duplication events. Despite their biological importance, CKX genes in Triticum aestivum have yet to be studied in depth. A total of 11 CKX subfamilies were identified with similar gene structures, motifs, domains, cis-acting elements, and an average signal peptide of 25 amino acid length was found. Introns, ranging from one to four, were present in the coding regions at a similar interval in major CKX genes. Putative cis-elements such as abscisic acid, auxin, salicylic acid, and low-temperature-, drought-, and light-responsive cis-regulatory elements were found in the promoter region of majority CKX genes. Variation in the expression pattern of CKX genes were identified across different tissues in Triticum. Phylogenetic analysis shows that the same subfamily of CKX clustered into a similar clade that reflects their evolutionary relationship. We performed a genome-wide identification of CKX family members in the Triticum aestivum genome to get their chromosomal location, gene structure, cis-element, phylogeny, synteny, and tissue- and stage-specific expression along with gene ontology. This study has also elaborately described the tissue- and stage-specific expression and is the resource for further analysis of CKX in the regulation of biotic and abiotic stress resistance, growth, and development in Triticum and other cereals to endeavor for higher production and proper management.
PMID: 36061212
Front Genet , IF:4.599 , 2022 , V13 : P932207 doi: 10.3389/fgene.2022.932207
Identification and Analysis of Long Non-Coding RNAs Related to UV-B-Induced Anthocyanin Biosynthesis During Blood-Fleshed Peach (Prunus persica) Ripening.
College of Horticulture Science and Technology, Hebei Normal University of Science and Technology, Qinhuangdao, China.; Hebei Key Laboratory of Horticultural Germplasm Excavation and Innovative Utilization, Qinhuangdao, China.; The Key Laboratory for Silviculture and Conservation of Ministry of Education, The College of Forestry, Beijing Forestry University, Beijing, China.; College of Agriculture and Animal Husbandry, Qinghai University, Xining, China.
Blood flesh is a key fruit trait in peaches (Prunus persica) and can be attributed to the accumulation of anthocyanins. The roles of long non-coding RNAs (lncRNAs) have been highlighted by multiple studies in regulating fruit ripening, anthocyanin accumulation, and abiotic stress responses in many flowering plants. Such regulatory functions of lncRNAs in Prunus persica, nonetheless, have not been reported. In this research, we sequenced and analyzed the complete transcriptome of C3-20 (a blood-fleshed peach) fruit at four developmental stages. Analyses of the correlated genes and differentially expressed lncRNA target genes helped to forecast lncRNAs' possible functions. The RNA-seq data were generated using high-throughput sequencing. In total, 17,456 putative lncRNAs, including 4,800 intergenic lncRNAs, 2,199 antisense lncRNAs, and 10,439 intronic lncRNAs were discovered, of which 4,871 differentially expressed lncRNAs (DE-lncRNAs) were annotated in the fruit developmental processes. The target genes of these DE-lncRNAs and their regulatory relationship identifying 21,795 cis-regulated and 18,271 trans-regulated targets of the DE-lncRNAs were in a similar way predicted by us. The enriched GO terms for the target genes included anthocyanin biosynthesis. Flavonoid biosynthesis and plant hormone signal transduction were also included in the enriched KEGG pathways. Co-expression network construction demonstrated that the highly expressed genes might co-regulate multiple other genes associated with auxin signal transduction and take effect in equal pathways. We discovered that lncRNAs, including LNC_000987, LNC_000693, LNC_001323, LNC_003610, LNC_001263, and LNC_003380, correlated with fruit that ripened and could take part in ethylene biosynthesis and metabolism and the ABA signaling pathway. Several essential transcription factors, such as ERFs, WRKY70, NAC56, and NAC72, may in a similar way regulate fruit ripening. Three DE-lncRNAs, XLOC_011933, XLOC_001865, and XLOC_042291, are involved in UV-B-induced anthocyanin biosynthesis and positively regulating UVR8 and COP10, were identified and characterized. Our discovery and characterization of XLOC_011933, XLOC_001865, and XLOC_042291 provide a more precise understanding and preliminarily establishes a theoretical framework for UV-B-induced flesh anthocyanin biosynthesis. This phenomenon might encourage more in-depth investigations to study the molecular mechanisms underlying peach flesh coloring.
PMID: 36017497
Plant Cell Rep , IF:4.57 , 2022 Aug doi: 10.1007/s00299-022-02921-7
Disruption of transcription factor RhMYB123 causes the transformation of stamen to malformed petal in rose (Rosa hybrida).
Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture, China Agricultural University, Beijing, China.; School of Applied Chemistry and Biotechnology, Shenzhen Polytechnic, Shenzhen, China.; Yunnan Yuntianhua Modern Agriculture Development Co., Ltd, Kunming, China.; College of Plant Science and Technology, Beijing University of Agriculture, Beijing, China.; Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture, China Agricultural University, Beijing, China. zhouxiaofeng@cau.edu.cn.
KEY MESSAGE: We find that the R2R3 MYB transcription factor RhMYB123 has a novel function to regulate stamen-petal organ specification in rose. Rose is one of the ornamental plants with economic importance worldwide. Malformed flower seriously affects the ornamental value and fertility of rose. However, the regulatory mechanism is largely unknown. In this work, we identified a R2R3 MYB transcription factor RhMYB123 from rose, the expression of which significantly decreased from flower differentiation stage to floral organ development stage. Phylogenetic analysis indicated that it belongs to the same subgroup as MYB123 of Arabidopsis and located in nucleus. In addition, RhMYB123 was confirmed to have transcriptional activation function by dual luciferase assay. Silencing RhMYB123 using Virus-Induced Gene Silencing (VIGS) in rose could increase the number of malformed petaloid stamen. Furthermore, we identified 549 differential expressed genes (DEGs) in TRV-RhMYB123 lines compared to TRV controls by RNA-seq of floral buds (flower differentiation stage). Among of those genes, expression of 3 MADS box family genes related to floral organ development reduced in TRV-RhMYB123 lines, including AGAMOUS (RhAG), AGAMOUS LIKE 15 (RhAGL15), and SHATTERPROOF 1 (RhSHP1). Given, previous studies have shown that auxin plays a crucial role in floral meristem initiation and stamen-petal organ specification. We also found 6 DEGs were involved in auxin signal transduction, of which five were reduced expression in TRV-RhMYB123. Taken together, our findings suggested that RhMYB123 may govern the development of malformed petaloid stamen by regulating the expressions of some MADS box family members and auxin signaling pathway elements.
PMID: 35999377
Plant Cell Rep , IF:4.57 , 2022 Sep , V41 (9) : P1895-1906 doi: 10.1007/s00299-022-02899-2
Heterologous expression of a Fraxinus velutina SnRK2 gene in Arabidopsis increases salt tolerance by modifying root development and ion homeostasis.
Shandong Provincial Key Laboratory of Plant Stress Research, College of Life Science, Shandong Normal University, Jinan, 250014, China.; Shandong Provincial Key Laboratory of Forest Tree Genetic Improvement, Shandong Academy of Forestry, Jinan, 250014, China. pangcaihong@shandong.cn.; Shandong Provincial Key Laboratory of Plant Stress Research, College of Life Science, Shandong Normal University, Jinan, 250014, China. chenminrundong@126.com.; Dongying Institute, Shandong Normal University, No. 2 Kangyang Road, Dongying, 257000, China. chenminrundong@126.com.
KEY MESSAGE: FvSnRK2182 is involved in regulating the growth and stress response. SnRK2 family members are positive regulators of downstream signals in the abscisic acid (ABA) signaling pathway, playing key roles in the plant responses to abiotic stresses. Fraxinus velutina Torr. is a candidate phytoremediator of saline-alkali areas, and is a valuable research subject because of its adaptability in saline soil. We identified a SnRK2 gene in F. velutina (named FvSnRK2182), which was significantly upregulated under salt stress. A bioinformatics analysis showed that FvSnRK2182 has a Ser/Thr kinase domain typical of the SnRK2 subfamily. Compared with wild-type (WT) Arabidopsis, its heterologous expression in Arabidopsis resulted in higher auxin content during seed germination and seedling growth, leading to longer primary roots and more lateral roots. The transgenic lines were better able to tolerate treatments with NaCl (100 mM) and/or ABA (0.2 and 0.5 microM), producing a greater biomass than the WT plants. Under NaCl treatment, the shoots of the transgenic lines had lower Na(+) contents and higher K(+) contents than the WT plants, and the genes encoding the ion transport-related proteins SOS1, HKT1, NHX1, and AKT1 were significantly upregulated. In addition, the expression of the genes functioning downstream of SnRK2 in the ABA signaling pathway (Rboh, AREB4, ABF2, and ABF3) were significantly upregulated in transgenic lines under NaCl stress. These results showed that expressing FvSnRK2182 in Arabidopsis significantly increased their resistance to ABA and salt stress by regulating root development and maintaining ion homeostasis, which suggests that FvSnRK2182 may be involved in regulating the growth and stress response of F. velutina.
PMID: 35794394
Plant Cell Rep , IF:4.57 , 2022 Sep , V41 (9) : P1875-1893 doi: 10.1007/s00299-022-02898-3
Cellular responses of oil palm genotypes during somatic embryogenesis involve participation of procambial cells, DNA demethylation, and auxin accumulation.
CNPq/Embrapa Postoctoral Fellowship Program, Embrapa Recursos Geneticos e Biotecnologia, Brasilia, DF, Brazil.; Laboratorio de Microscopia, Embrapa Recursos Geneticos e Biotecnologia, Brasilia, DF, Brazil.; Laboratorio de Microscopia, Embrapa Recursos Geneticos e Biotecnologia, Brasilia, DF, Brazil. jonny.pereira@embrapa.br.; Laboratorio de Cultura de Tecidos e Genetica Vegetal, Embrapa Recursos Geneticos e Biotecnologia, Brasilia, DF, Brazil. jonny.pereira@embrapa.br.
KEY MESSAGE: Cell markers of somatic embryogenesis initiation from leaf tissues in oil palm involve the participation of procambial cells, DNA demethylation, and auxin accumulation. Low callogenesis and genotype-dependent response have been mentioned in the development of somatic embryogenesis protocols of Elaeis oleifera x E. guineensis elite hybrids, which requires more detailed investigations of the process. Thus, the initial cellular responses of immature leaves of adult genotypes of this hybrid were investigated for the first time, emphasizing histological, epigenetic, and endogenous auxin changes. Leaf segments from two genotypes, one responsive to somatic embryogenesis (B351733) and another non-responsive (B352933), were inoculated in Murashige and Skoog medium with 450 microM of 4-amino-3, 5, 6-trichloropicolinic acid. For anatomical analysis, samples of both genotypes were collected at 0, 20, 90, and 105 days of cultivation. Samples of both genotypes were also taken at different cultivation periods to analyze DNA methylation status (% 5-mC-5 methylcytosine) via ELISA test. Immunolocalization assays were performed with anti-indole-3-acetic acid and anti-5-methyl-deoxycytosine antibodies from samples of hybrid B351733. We distinguished two groups of cells reactive to the induction of embryogenic callogenesis, parenchymatous sheath cells, and procambial cells; however, only the latter are directly involved with the formation of calluses. The data obtained indicate that the formation of calluses in hybrid B351733 is related to DNA hypomethylation, while the non-responsiveness of leaf explants in hybrid B352932 is related to DNA hypermethylation. The in situ immunolocalization enabled the identification of initial markers of the callogenic process, such as IAA accumulation and hypomethylation. Identifying these events brings the possibility of establishing strategies for efficient manipulation of somatic embryogenesis protocols in palm trees.
PMID: 35776139
Physiol Plant , IF:4.5 , 2022 Sep : Pe13774 doi: 10.1111/ppl.13774
Cellular differentiation, hormonal gradient, and molecular alternation between the division zone and the elongation zone of bamboo internodes.
Co-Innovation Center for Sustainable Forestry in Southern China, Bamboo Research Institute, Key Laboratory of National Forestry and Grassland Administration on Subtropical Forest Biodiversity Conservation, College of Biology and the Environment, Nanjing Forestry University, Nanjing, Jiangsu, China.; Jiangxi Provincial Key Laboratory for Bamboo Germplasm Resources and Utilization, Jiangxi Agriculture University, Nanchang, Jiangxi, China.; Boyce Thompson Institute, Cornell University, 533 Tower Road, Ithaca, NY, USA.; Present address: College of Agriculture and Biotechnology, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang, China.
Bamboo differentiates a cell division zone (DZ) and a cell elongation zone (EZ) to promote internode elongation during rapid growth. However, the biological mechanisms underlying this sectioned growth behavior are still unknown. Using histological, physiological, and genomic data, we found that the cell wall and other subcellular organelles such as chloroplasts are more developed in the EZ. Abundant hydrogen peroxide accumulated in the pith cells of the EZ, and stomata formed completely in the EZ. In contrast, most cells in the DZ were in an undifferentiated state with wrinkled cell walls and dense cytoplasm. Hormone detection revealed that the levels of gibberellin, auxin, cytokinin, and brassinosteroid were higher in the DZ than in the EZ. However, the levels of salicylic acid and jasmonic acid were higher in the EZ than in the DZ. Transcriptome analysis with qRT-PCR quantification revealed that the transcripts for cell division and primary metabolism had higher expression in the DZ, whereas the genes for photosynthesis, cell wall growth, and secondary metabolism were dramatically upregulated in the EZ. Overexpression of a MYB transcription factor, BmMYB83, promotes cell wall lignification in transgenic plants. BmMYB83 is specifically expressed in cells that may have lignin deposits, such as protoxylem vessels and fiber cells. Our results indicate that hormone gradient and transcriptome reprogramming, as well as specific expression of key genes such as BmMYB83, may lead to differentiation of cell growth in the bamboo internode. This article is protected by copyright. All rights reserved.
PMID: 36050899
Molecules , IF:4.411 , 2022 Sep , V27 (18) doi: 10.3390/molecules27185806
Nitric Oxide Is Essential for Melatonin to Enhance Nitrate Tolerance of Cucumber Seedlings.
College of Horticulture, South China Agricultural University, Guangzhou 510642, China.
Melatonin (MT) and nitric oxide (NO) in plants can function cooperatively to alleviate salt stress, sodic alkaline stress and immune response, as well as adventitious root formation. The interaction of MT and NO on the nitrate stress tolerance of cucumber seedlings are not well understood. We investigated the effects of exogenous MT, NO donor (SNP) and NO scavenger (cPTIO) on the growth; photosynthesis; characteristics of root morphological; accumulation of mineral elements, endogenous NO, MT, IAA and ABA; and related genes expression in cucumber (Cucumis sativus L. "Jin You No. 1") seedlings grown under high nitrate condition (HN). The results showed that MT and NO independently alleviated the inhibition of growth and photosynthesis capacity of cucumber seedlings under nitrate stress. NO was required for MT to enhance the root activity, root length, lateral root number and the accumulation of calcium, magnesium and iron in the roots of cucumber seedlings grown under nitrate stress. Consistently, the expression of adventitious rootless 1 gene (CsARL1) was modulated. Furthermore, exogenous MT induced accumulation of endogenous MT, NO, indole-3-acetic acid (IAA) and abscisic acid (ABA), mainly within 24 h after treatment, in which MT and NO were further increased at 48 h and 96 h, IAA and ABA were further increased at 16 h in the presence of SNP. In contrast, the accumulation of endogenous IAA, MT and ABA slightly decreased within 24 h, NO significantly decreased at 192 h in the presence of cPTIO. Correspondingly, the expression levels of genes involved in nitrogen metabolism (CsNR1 and CsNR2), MT metabolism (CsT5H, CsSNAT2 and Cs2-ODD33), auxin carriers and response factors (CsAUX1, CsGH3.5, CsARF17), ABA synthesis and catabolism (CsNCED1, CsNCED3 and CsCYP707A1) were upregulated by MT, in which CsNR1, CsNR2, CsAUX1, CsNCED3 and CsT5H were further induced in the presence of SNP in roots of cucumber seedlings. These observations indicated that NO act as a crucial factor in MT, alleviating nitrate stress through regulating the mechanism of root growth in cucumber seedlings.
PMID: 36144541
Molecules , IF:4.411 , 2022 Aug , V27 (16) doi: 10.3390/molecules27165051
Growth Stimulation, Phosphate Resolution, and Resistance to Fungal Pathogens of Some Endogenous Fungal Strains in the Rhizospheres of Medicinal Plants in Vietnam.
University of Economics-Technology for Industries (UNETI), Hanoi 11622, Vietnam.; Institute of Biotechnology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Hanoi 11307, Vietnam.; Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Hanoi 11307, Vietnam.; School of Materials Science and Energy Engineering, Graduate University of Science and Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay District, Hanoi 11307, Vietnam.
Endophytic fungi are recognized for their many potential applications in agriculture, such as supporting cropland expansion and increasing the yield and resistance of plants by creating antibiotics that inhibit the growth of pathogenic microorganisms. In addition, they can produce enzymes that break down hard-to-solubilize substances within soil, dissolve phosphates, fix nitrogen, reduce metals, and produce hormones that promote plant growth (auxin, cytokinin, and gibberellins) to keep crops healthy. In this report, three strains of endophytic fungi, namely, N1, N2, and N3, were isolated from the roots of Stevia rebaudiana (Bert.) Hemsl., Polyscias fruticosa, and Angelica dahurica in some localities in Vietnam. Through a screening process, it was found that they can produce high levels of indole acetic acid (IAA), resolve phosphates, and resist disease, and they were selected to as an alternative to chemical fertilizers to make probiotics in order to increase medicinal plant yields. The results show that the three strains of fungi have the ability to degrade phosphate to 341.90, 1498.46, and 390.79 ppm; the content of IAA produced in the culture medium reached 49.00, 52.35, and 33.34 ppm. Based on some morphological characteristics and an internal transcribed spacer gene sequence analysis of the fungal strains, N1, N2, and N3 were named Penicillium simplicissimum CN7, Talaromyces flavus BC1, and Trichoderma konilangbra DL3, respectively, which have the ability to inhibit the growth of pathogenic fungal strains, such as fungus C. gloeosporioides (CD1), fungus F. oxysporum, fungus L. theobromae N13, and N. dimidiatum. They grow significantly over a period of 5 to 6 days.
PMID: 36014291
Sci Rep , IF:4.379 , 2022 Sep , V12 (1) : P15027 doi: 10.1038/s41598-022-19399-8
Common and novel metabolic pathways related ESTs were upregulated in three date palm cultivars to ameliorate drought stress.
Department of Arid Land Agriculture, College of Agriculture and Food Sciences, King Faisal University, PO Box 31982, Al-Ahsa, Saudi Arabia.; Date Palm Research Center of Excellence, King Faisal University, PO Box 31982, Al-Ahsa, Saudi Arabia.; Central Laboratories, King Faisal University, PO Box 31982, Al-Ahsa, Saudi Arabia. zafar@kfu.edu.sa.
Date palm is an important staple crop in Saudi Arabia, and about 400 different date palm cultivars grown here, only 50-60 of them are used commercially. The most popular and commercially consumed cultivars of these are Khalas, Reziz, and Sheshi, which are also widely cultivated across the country. Date palm is high water-demanding crop in oasis agriculture, with an inherent ability to tolerate drought stress. However, the mechanisms by which it tolerates drought stress, especially at the transcriptomic level, are still elusive. This study appraised the physiological and molecular response of three commercial date palm cultivars Khalas, Reziz, and Sheshi at two different field capacities (FC; 100% and 25%) levels. At 25% FC (drought stress), leaf relative water content, chlorophyll, photosynthesis, stomatal conductance, and transpiration were significantly reduced. However, leaf intercellular CO2 concentration and water use efficiency increased under drought stress. In comparison to cvs. Khalas and Reziz, date palm cv. Sheshi showed less tolerance to drought stress. A total of 1118 drought-responsive expressed sequence tags (ESTs) were sequenced, 345 from Khalas, 391 from Reziz, and 382 from Sheshi and subjected to functional characterization, gene ontology classification, KEGG pathways elucidation, and enzyme codes dissemination. Three date palm cultivars deployed a multivariate approach to ameliorate drought stress by leveraging common and indigenous molecular, cellular, biological, structural, transcriptional and reproductive mechanisms. Approximately 50% of the annotated ESTs were related to photosynthesis regulation, photosynthetic structure, signal transduction, auxin biosynthesis, osmoregulation, stomatal conductance, protein synthesis/turnover, active transport of solutes, and cell structure modulation. Along with the annotated ESTs, ca. 45% of ESTs were novel. Conclusively, the study provides novel clues and opens the myriads of genetic resources to understand the fine-tuned drought amelioration mechanisms in date palm.
PMID: 36056140
Sci Rep , IF:4.379 , 2022 Aug , V12 (1) : P14031 doi: 10.1038/s41598-022-17839-z
Transcriptome analysis of halophyte Nitraria tangutorum reveals multiple mechanisms to enhance salt resistance.
Qinghai Provincial Key Laboratory of High-Value Utilization of Characteristic Economic Plants, Qinghai Minzu University, Xining, 810007, China.; Institute of Ecology and Environment of Qinghai-Tibet Plateau, Qinghai Minzu University, Xining, 810007, China.; College of Forestry, Gansu Agricultural University, Lanzhou, 730000, China.; Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, 730000, China.; College of Eco-Environmental Engineering, Qinghai University, Xining, 810016, China.; Lanzhou Agriculture and Rural Affairs Bureau in Gansu Province, Lanzhou, 730030, China.; College of Forestry, Gansu Agricultural University, Lanzhou, 730000, China. liyi@gsau.edu.cn.; Qinghai Provincial Key Laboratory of High-Value Utilization of Characteristic Economic Plants, Qinghai Minzu University, Xining, 810007, China. wangjiuli12@mails.ucas.ac.cn.; Institute of Ecology and Environment of Qinghai-Tibet Plateau, Qinghai Minzu University, Xining, 810007, China. wangjiuli12@mails.ucas.ac.cn.
As a typical halophyte, Nitraria tangutorum Bobr. has attracted the interest of many researchers with the excellent salt tolerance. Elucidation of the mechanism of N. tangutorum salinity tolerance will facilitate the genetic improvement of productive plants faced with salinity. To reveal the molecular response to gradually accumulated salt stress in N. tangutorum, RNA-sequencing and analysis of gradually accumulated NaCl treated samples and control samples were performed, and a total of 1419 differentially expressed genes were identified, including 949 down-regulated genes and 470 up-regulated genes. Detailed analysis uncovered that the catabolism of organic compounds mainly based on oxidative phosphorylation genes was up-regulated. Additionally, various antioxidant genes, especially anthocyanin-related genes, were found to help N. tangutorum remove reactive oxygen species. Moreover, the Mitogen activated protein kinase signaling pathway and other signaling pathways co-regulated various salt tolerance activities. Additionally, intracellular ion homeostasis was maintained via regulation of osmotic regulator-related genes, cutin-related genes, and cell elongation-related genes to retain cellular water and reduce ion concentration. In particularly, simultaneous up-regulation in cytoskeleton-related genes, cell wall-related genes, and auxin-related genes, provided evidence of important role of cell expansion in plant salt tolerance. In conclusion, complex regulatory mechanisms modulated by multiple genes might contribute to the salt tolerance by N. tangutorum.
PMID: 35982183
Plant Physiol Biochem , IF:4.27 , 2022 Nov , V190 : P1-10 doi: 10.1016/j.plaphy.2022.08.020
Liriodendron chinense LcMAX1 regulates primary root growth and shoot branching in Arabidopsis thaliana.
Key Laboratory of Forest Genetics & Biotechnology of Ministry of Education, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China; Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China. Electronic address: Winnie@njfu.edu.cn.; Key Laboratory of Forest Genetics & Biotechnology of Ministry of Education, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China; Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China. Electronic address: zhonghuatu@njfu.edu.cn.; Key Laboratory of Forest Genetics & Biotechnology of Ministry of Education, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China; Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China. Electronic address: lmwei@njfu.edu.cn.; Key Laboratory of Forest Genetics & Biotechnology of Ministry of Education, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China; Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China. Electronic address: hgli@njfu.edu.cn.
Strigolactones (SLs) play prominent roles in regulating shoot branching and root architecture in model plants. However, their roles in non-model (particularly woody) plants remain unclear. Liriodendron chinense is a timber tree species widely planted in southern China. The outturn percentage and wood quality of L. chinense are greatly affected by the branching characteristics of its shoot, and the rooting ability of the cuttings is key for its vegetative propagation. Here, we isolated and analyzed the function of the MORE AXILLARY GROWTH 1 (LcMAX1) gene, which is involved in L. chinense SL biosynthesis. RT-qPCR showed that LcMAX1 was highly expressed in the roots and axillary buds. LcMAX1 was located in the endoplasmic reticulum (ER) and nucleus. LcMAX1 ectopic expression promoted primary root growth, whereas there were no phenotypic differences in shoot branching between transgenic and wild-type (WT) A. thaliana plants. LcMAX1 overexpression in the max1 mutant restored them to the WT A. thaliana phenotypes. Additionally, AtPIN1, AtPIN2, and AtBRC1 expressions were significantly upregulated in transgenic A. thaliana and the max1 mutant. It was therefore speculated that LcMAX1 promotes primary root growth by regulating expression of auxin transport-related genes in A. thaliana, and LcMAX1 inhibits shoot branching by upregulating expression of AtBRC1 in the max1 mutant. Altogether, these results demonstrated that the root development and shoot branching functions of LcMAX1 were similar to those of AtMAX1. Our findings provide a foundation for obtaining further insights into root and branch development in L. chinense.
PMID: 36084353
Plant Physiol Biochem , IF:4.27 , 2022 Sep , V186 : P182-196 doi: 10.1016/j.plaphy.2022.07.002
Exogenous spermidine regulates the anaerobic enzyme system through hormone concentrations and related-gene expression in Phyllostachys praecox roots under flooding stress.
State Key Lab of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China; University of Chinese Academy of Sciences, Beijing, 100049, China.; College of Forestry, Nanjing Forestry University, 159 Longpan Road, Nanjing, 210037, China.; State Key Lab of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China. Electronic address: syzhuang@issas.ac.cn.
PURPOSE: Acclimation to hypoxia and anoxia is important in various ecological systems, especially flooded soil. Phyllostachys pracecox is sensitive to flooding, and therefore, it is important to explore ways of alleviating hypoxia stress in the roots. In this study, we investigated the regulatory effect of spermidine (Spd) on flooded P. praecox seedlings. METHODS: A batch experiment was carried out in roots treated with Spd under flooding for eight days. The following factors were subsequently measured: growth, survival rate, root respiratory activity, soluble protein and anaerobic respiration enzyme contents (pyruvate decarboxylase, PDC; alcohol dehydrogenase, ADH; lactate dehydrogenase, LDH; alanine aminotransferase, AlaAT), S-adenosylmethionine decarboxylase (SAMDC), nitrate reductase (NR), ACC oxidase (ACO) and ACC synthetase (ACS) activities, free Spd, spermine (Spm) and the diamine precursor putrescine (Put) content, indole-3-acetic acid (IAA) and abscisic acid (ABA) content, ethylene emissions and expression of hormone-related genes. RESULTS: Application of Spd promoted root growth (root length, volume, surface and dry weight) and root respiratory inhibition, improved the soluble protein content, and reduced the O2(.-) production rate, H2O2 and MDA content to alleviate the damage of roots under flooding. A significant increase in SAMDC activity, and ABA and IAA contents were also observed, along with a reduction in ethylene emissions, NR, ACO and ACS activities (p < 0.05). Exogenous Spd increased the free Spd and Spm contents in the P. praecox roots, but decreased the free Put content. Taken together, these findings suggest that hypoxia stress was alleviated. Moreover, exogenous Spd up-regulated the expression of auxin-related genes ARF1, AUX1, AUX2, AUX3 and AUX4, and down-regulated the expression of ethylene-related ACO and ACS genes during flooding. In addition, correlation and RDA analysis showed that ARF1, ACO and ACS significantly promoted the expression of auxin, ACO and ACS enzyme activities, respectively (p < 0.05), while ADH, NR, AlaAT, ethylene emissions, Put, Spd, ACS and ACO were significantly correlated with ACS, ACO, and auxin-related gene expression (p < 0.05). Overall, ethylene emissions, ACS and ACO were identified as the main drivers of ethylene and auxin-related gene structure. CONCLUSIONS: These results suggest that Spd regulated hormone concentrations, the content of Spd, Spm and Put, and related gene expression, in turn regulating physiological changes such as anaerobic enzyme activity, mitigating flooding stress in the roots and improving overall growth. Spd therefore has the potential to improve the adaptability of P. praecox to flooding stress.
PMID: 35868108
Plant Physiol Biochem , IF:4.27 , 2022 Sep , V186 : P31-39 doi: 10.1016/j.plaphy.2022.06.029
Ultra-low concentration of chlorine dioxide regulates stress-caused premature leaf senescence in tobacco by modulating auxin, ethylene, and chlorophyll biosynthesis.
Anhui Provincial Engineering Laboratory for Efficient Utilization of Featured Resource Plants, College of Life Sciences, Huaibei Normal University, Huaibei, Anhui, 235000, PR China. Electronic address: 1535950539@qq.com.; Anhui Provincial Engineering Laboratory for Efficient Utilization of Featured Resource Plants, College of Life Sciences, Huaibei Normal University, Huaibei, Anhui, 235000, PR China. Electronic address: 1328454086@qq.com.; Anhui Provincial Engineering Laboratory for Efficient Utilization of Featured Resource Plants, College of Life Sciences, Huaibei Normal University, Huaibei, Anhui, 235000, PR China. Electronic address: 2135291758@qq.com.; Anhui Provincial Engineering Laboratory for Efficient Utilization of Featured Resource Plants, College of Life Sciences, Huaibei Normal University, Huaibei, Anhui, 235000, PR China. Electronic address: 1938840527@qq.com.; Anhui Provincial Engineering Laboratory for Efficient Utilization of Featured Resource Plants, College of Life Sciences, Huaibei Normal University, Huaibei, Anhui, 235000, PR China. Electronic address: 1796482382@qq.com.; Anhui Provincial Engineering Laboratory for Efficient Utilization of Featured Resource Plants, College of Life Sciences, Huaibei Normal University, Huaibei, Anhui, 235000, PR China. Electronic address: 2296365488@qq.com.; Anhui Provincial Engineering Laboratory for Efficient Utilization of Featured Resource Plants, College of Life Sciences, Huaibei Normal University, Huaibei, Anhui, 235000, PR China. Electronic address: xuetao_26@163.com.; Anhui Provincial Engineering Laboratory for Efficient Utilization of Featured Resource Plants, College of Life Sciences, Huaibei Normal University, Huaibei, Anhui, 235000, PR China. Electronic address: zhaofenglan2004@163.com.; Anhui Provincial Engineering Laboratory for Efficient Utilization of Featured Resource Plants, College of Life Sciences, Huaibei Normal University, Huaibei, Anhui, 235000, PR China. Electronic address: biosw2006@126.com.; Anhui Provincial Engineering Laboratory for Efficient Utilization of Featured Resource Plants, College of Life Sciences, Huaibei Normal University, Huaibei, Anhui, 235000, PR China. Electronic address: yboduan@163.com.
Exploring novel growth regulators for premature senescence regulation is important for tobacco production. In the present study, chlorine dioxide (ClO2) was explored as a novel plant growth regulator for tobacco growth, particularly its effect on leaf senescence and root development. The results showed that 0.15 muM ClO2 maintained the lushness of detached leaves and whole plants. Also, the leaves of ClO2-treated plants exhibited a chlorophyll content of 58% higher than in CK (control) plants (P < 0.05). Besides, ClO2 treatment increased the biomass of roots and aboveground parts by 54 and 16%, respectively. The ClO2-treated plants also showed enhanced activities of antioxidant enzymes and significantly reduced malondialdehyde contents (P < 0.05). Moreover, ClO2 treatment remarkably alleviated drought-caused premature senescence in the tobacco plants and partly rescued the exogenous ethylene-caused plant dwarfism. The indole-3-acetic acid content in ClO2-treated plants was higher than in non-treated plants (P < 0.05), but ethylene content was significantly lower (P < 0.05). Gene expression analysis showed that ClO2 treatment remarkably suppressed ethylene synthase genes. However, the auxin biosynthesis and transport genes were up-regulated, with NtIAA17 increasing by five folds (P < 0.05). Further, ClO2 remarkably up-regulated the expression of chlorophyll biosynthesis genes, with a >20-fold increase in NtHEMA1 and NtCHLH expressions. These results designate ClO2 as a potential regulator for improving tobacco productivity by retaining higher chlorophyll content and promoting root growth.
PMID: 35803089
Plant Physiol Biochem , IF:4.27 , 2022 Aug , V185 : P260-267 doi: 10.1016/j.plaphy.2022.06.013
Mechanism of pod shattering in the forage legume Medicago ruthenica.
Grassland Research Institute, Chinese Academy of Agricultural Sciences, Hohhot, China.; Grassland and Resources Environment Institute, Inner Mongolia Agriculture University, Hohhot, China.; Grassland Supervision Office, Chahar Right Back Banner, Ulanqab, China.; Grassland Research Institute, Chinese Academy of Agricultural Sciences, Hohhot, China. Electronic address: zhiyongli1216@126.com.; Grassland Research Institute, Chinese Academy of Agricultural Sciences, Hohhot, China; Key Laboratory of Herbage & Endemic Crop Biology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, China. Electronic address: lijun1538@126.com.
Pod shattering is a seed dispersal strategy and an important agronomical trait in domesticated crops. The relationship between pod shattering and pod morphology in the genus Medicago is well known; however, the detailed mechanism underlying pod dehiscence in Medicago ruthenica, a perennial legume used for forage production, is unknown. Here, the pod ventral sutures of shatter-resistant and shatter-susceptible M. ruthenica genotypes were examined at 8, 12, 16, and 20 d after flowering. The mechanism of pod shattering was analyzed through microscopic observations, polygalacturonase (PG) and cellulase (CE) activity analyses, and RNA-sequencing (RNA-Seq), and the results were verified via reverse transcriptase-quantitative polymerase chain reaction. Pod shattering at the ventral suture in M. ruthenica occurs via a combination of two mechanisms: degradation of the middle lamella at the abscission layers (ALs) and detachment of lignified cells on either side of the ALs triggered by physical forces. Increased PG and CE activities in the pod ventral suture are essential for AL cell-autolysis in the shatter-susceptible genotype. RNA-Seq revealed that 11 genes encoding PG and CE were highly expressed in the ventral sutures of the shatter-susceptible genotype. The expression levels of auxin biosynthesis-related genes decreased in the AL cells and they were negatively associated with pod dehiscence. These results enhance our understanding of the pod shattering mechanism not only in M. ruthenica but also in other leguminous plants.
PMID: 35717734
Plant Physiol Biochem , IF:4.27 , 2022 Aug , V185 : P244-259 doi: 10.1016/j.plaphy.2022.06.006
Auxin regulates growth, photosynthetic efficiency and mitigates copper induced toxicity via modulation of nutrient status, sugar metabolism and antioxidant potential in Brassica juncea.
Department of Botany, Plant Physiology Section, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, 202002, India.; Department of Biology, College of Science and Humanities in Al-Kharj, Prince Sattam Bin Abdulaziz University, 11942, Saudi Arabia.; Department of Botany, Plant Physiology Section, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, 202002, India. Electronic address: hayat_68@yahoo.co.in.
The involvement of auxin (IAA) in growth and development of plants is well known, but its role in the mitigation of metal stress, especially copper (Cu), is not fully understood; therefore, it is time to explore its involvement in minimizing the stress. A pot experiment was conducted to assess the protective function of IAA, applied to the foliage, on photosynthetic machinery, carbohydrate metabolism, and growth of Brassica juncea, grown with Cu (30 or 60 mg kg(-1) of soil). Among the different concentrations (10(-10), 10(-8), or 10(-6) M), 10(-8) M of IAA alone enhanced the photosynthetic characteristics, sugar accumulation and vegetative growth with minimal cellular oxidative stress level. Moreover, the same concentration of auxin was most effective in decreasing the stress levels generated by Cu and maintained it nearly to that of the control in terms of photosynthetic attributes, gas exchange parameters, PSII activity, electron transport rate, and growth attributes. Auxin also maintained the membrane stability and ultrastructure of chloroplast, stomatal morphology with a reduction in malondialdehyde (MDA), electrolyte leakage (EL) and cell death in test plants even under Cu stress. IAA also improved the translocation of Cu from root to the aerial parts, thus enhanced the Cu-reclamation in metal contaminated soils. Our findings suggest that the application of 10(-8) M of IAA maintains the overall growth of plants and may be used as an effective agent to improve growth, photosynthesis and phyto-remediation potential of B. juncea in Cu contaminated soil.
PMID: 35717733
BMC Plant Biol , IF:4.215 , 2022 Sep , V22 (1) : P456 doi: 10.1186/s12870-022-03837-w
Analysis of controlling genes for tiller growth of Psathyrostachys juncea based on transcriptome sequencing technology.
College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot, 010018, China.; College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot, 010018, China. yunlan@imau.edu.cn.; Key Laboratory of Grassland Resources of the Ministry of Education and Key Laboratory of Forage Cultivation, Processing and High Efficient Utilization of the Ministry of Agriculture, Hohhot, 010018, China. yunlan@imau.edu.cn.
BACKGROUND: Tillering is a complicated process in plant and is a significant trait that affects biomass and seed yield of bunch grass Psathyrostachys juncea, a typical perennial forage species. To clarify the regulatory mechanisms of tillering in P. juncea and to explore related candidate genes could be helpful to improve the seed and forage yield of perennial gramineous forages. We selected the tiller node tissues of P. juncea for transcriptome sequencing to determine the differentially expressed genes (DEG) between dense and sparse tillering genotypes. The metabolic pathway was studied, candidate genes were screened, and reference genes stability were evaluated. RESULTS: The results showed that approximately 5466 DEGs were identified between the two genotypes with dense and sparse tillers of P. juncea, which significantly differed in tiller number. Tillering regulation pathways analysis suggested that DEGs closely related to the biosynthesis of three plant hormones, namely auxin (IAA), cytokinin (CTK), and strigolactones (SLs), while "biosynthesis of lignin" and "nitrogen metabolism" have remarkable differences between the dense and sparse tillering genotypes. Meanwhile, the reference gene Actin1, having the best stability, was screened from twelve genes with highest expression level and was used in verification of ten tillering related candidate genes. CONCLUSIONS: The tillering mechanism of perennial grass P. juncea was expounded by transcriptome analysis of tiller node tissues. We demonstrated that dense-tillering genotypes may be distinguished by their low expression patterns of genes involved in SL, IAA, and high expression patterns of genes involved in CTK biosynthesis at the tillering stage, and nitrogen metabolism and lignin biosynthesis can also affect the number of tillers. Furthermore, the expression level of ten tillering related candidate genes were verified using Actin1 as reference gene. These candidate genes provide valuable breeding resources for marker assisted selection and yield traits improvement of P. juncea.
PMID: 36151542
BMC Plant Biol , IF:4.215 , 2022 Sep , V22 (1) : P427 doi: 10.1186/s12870-022-03810-7
Hormone biosynthesis and metabolism members of 2OGD superfamily are involved in berry development and respond to MeJA and ABA treatment of Vitis vinifera L.
Beijing Key Laboratory of Grape Science and Enology, CAS Key Laboratory of Plant Resources, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China.; University of Chinese Academy of Sciences, Beijing, 100049, China.; Key Laboratory of Beijing for Identification and Safety Evaluation of Chinese Medicine, Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, 100700, China.; Beijing Key Laboratory of Grape Science and Enology, CAS Key Laboratory of Plant Resources, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China. zl249@ibcas.ac.cn.
BACKGROUND: Hormones play an indispensable role during fruit ripening, nine clades in 2-oxoglutarate-dependent dioxygenase (2OGD) superfamily are responsible for the hormone biosynthesis and metabolism, but less information is known about them. RESULTS: A total of 163 Vv2OGD superfamily members were identified from grape genome, which were mainly expanded by local (tandem and proximal) duplication. Phylogenetic analysis of 2OGD members in grape and Arabidopsis indicates 37 members in Vv2OGD superfamily are related to hormone biosynthesis and metabolism process (Vv2OGD-H), which could be divided into 9 clades, gibberellin (GA) 3-oxidase (GA3ox), GA 20-oxidase (GA20ox), carbon-19 GA 2-oxidase (C19-GA2ox), carbon-20 GA 2-oxidase (C20-GA2ox), 1-aminocyclopropane-1-carboxylic acid oxidase (ACO), dioxygenase for auxin oxidation (DAO), lateral branching oxidoreductas (LBO), downy mildew resistant 6 and DMR6-like oxygenase (DMR6/DLO) and jasmonate-induced oxygenase (JOX). Sixteen of these 37 Vv2OGD-Hs are expressed in grape berry, in which the expression patterns of VvGA2oxs, VvDAOs and VvJOXs shows a correlation with the change patterns of GAs, indole-3-acetic acid (IAA) and jasmonates (JAs), indicating the involvement of these genes in grape berry development by regulating corresponding hormones. Twelve Vv2OGD-Hs respond to methyl JA (MeJA) treatment, of which eight may lead to the inhibition of the ripening process by the crosstalk of JAs-salicylic acids (SAs), JAs-GAs and JAs-JAs, while seven Vv2OGD-Hs respond to ABA treatment may be responsible for the promotion of ripening process by the interplay of abscisic acid (ABA)-strigolactones (SLs), ABA-SAs, ABA-GAs, ABA-JAs. Especially, VvLBO1 reach an expression peak near veraison and up-regulate about four times after ABA treatment, which implies SLs and ABA-SLs crosstalk may be related to the onset of berry ripening in grape. CONCLUSIONS: This study provides valuable clues and new insights for the mechanism research of Vv2OGD-Hs in hormones regulation during the grape berry development.
PMID: 36064347
BMC Plant Biol , IF:4.215 , 2022 Sep , V22 (1) : P423 doi: 10.1186/s12870-022-03799-z
TaPYL4, an ABA receptor gene of wheat, positively regulates plant drought adaptation through modulating the osmotic stress-associated processes.
State Key Laboratory of North China Crop Improvement and Regulation, Baoding, Hebei, 071001, People's Republic of China.; College of Agronomy, Hebei Agricultural University, Baoding, 071001, People's Republic of China.; Key Laboratory of Crop Growth Regulation of Hebei Province, Baoding, People's Republic of China.; State Key Laboratory of North China Crop Improvement and Regulation, Baoding, Hebei, 071001, People's Republic of China. xiaokai@hebau.edu.cn.; College of Agronomy, Hebei Agricultural University, Baoding, 071001, People's Republic of China. xiaokai@hebau.edu.cn.; Key Laboratory of Crop Growth Regulation of Hebei Province, Baoding, People's Republic of China. xiaokai@hebau.edu.cn.
BACKGROUND: Abscisic acid receptors (ABR) involve transduction of the ABA signaling in plants, impacting largely on stress-defensive physiological processes and plant osmotic stress response. In this study, we characterized TaPYL4, a gene of ABR family in T. aestivum, in mediating plant drought tolerance given scarcity of functional characterization on wheat ABR members thus far. RESULTS: TaPYL4 harbors nine conserved domains shared by its PYL counterparts, targeting onto plasma membrane and nucleus after endoplasmic reticulum assortment. TaPYL4 interacts with TaPP2C2 whereas the latter with TaSnRK2.1, which establish a core module of the ABA signaling pathway. TaPYL4 expression was upregulated in root and aerial tissues upon drought stress. Overexpressing TaPYL4 conferred plants improved growth traits whereas knockdown expression of target gene alleviated growth feature compared with wild type under drought treatment. The TaPYL4-enhanced drought adaptation associates gene function in positively regulating stomata movement, osmolyte biosynthesis, and root system architecture (RSA) establishment. Expression analysis on the P5CS family genes involving proline biosynthesis indicated that TaP5CS1 exerts critical roles in promoting osmolytes accumulation in drought-challenged TaPYL4 lines. TaPIN9, a PIN-FORMED gene modulating cellular auxin translocation, was validated to function as a crucial mediator in defining RSA establishment underlying TaPYL4 regulation. Transcriptome analysis revealed that TaPYL4 controls transcription of numerous genes, which impact on physiological processes associated with 'biological process', 'molecular component', and 'cellular process'. Moreover, the differentially expressed genes mediated by TaPYL4 were closely related to stress defensive pathways. CONCLUSIONS: Our investigation suggested that TaPYL4 acts as a positive regulator in plant drought tolerance and a valuable target for engineering drought-tolerant cultivars in T. aestivum.
PMID: 36050643
BMC Plant Biol , IF:4.215 , 2022 Sep , V22 (1) : P422 doi: 10.1186/s12870-022-03785-5
Silicon enhances the drought resistance of peach seedlings by regulating hormone, amino acid, and sugar metabolism.
State Key Laboratory of Crop Biology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, 271018, China.; State Key Laboratory of Crop Biology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, 271018, China. ysxiao@sdau.edu.cn.; State Key Laboratory of Crop Biology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, 271018, China. pft@sdau.edu.cn.
BACKGROUND: Drought is one of the main concerns worldwide and restricts the development of agriculture. Silicon improves the drought resistance of plants, but the underlying mechanism remains unclear. RESULTS: We sequenced the transcriptomes of both control and silicon-treated peach seedlings under drought stress to identify genes or gene networks that could be managed to increase the drought tolerance of peach seedlings. Peach (Prunus persica) seedlings were used to analyse the effects of silicon on plant growth and physiological indexes related to drought resistance under drought stress. The results showed that silicon addition improved the water use efficiency, antioxidant capacity, and net photosynthetic rate, inhibition of stomatal closure, promoted the development of roots, and further regulated the synthesis of hormones, amino acids and sugars in peach seedlings. A comparative transcriptome analysis identified a total of 2275 genes that respond to silicon under drought stress. These genes were mainly involved in ion transport, hormone and signal transduction, biosynthetic and metabolic processes, stress and defence responses and other processes. We analysed the effects of silicon on the modulation of stress-related hormonal crosstalk and amino acid and sugar metabolism. The results showed that silicon promotes zeatin, gibberellin, and auxin biosynthesis, inhibits the synthesis of abscisic acid, then promote lateral root development and inhibit stomatal closure, and regulates the signal transduction of auxin, cytokinin, gibberellin and salicylic acid. Silicon also regulates the metabolism of various amino acids and promotes the accumulation of sucrose and glucose to improve drought resistance of peach seedlings. CONCLUSIONS: Silicon enhanced the drought resistance of peach seedlings by regulating stress-related hormone synthesis and signal transduction, and regulating amino acid and sugar metabolism.
PMID: 36045325
BMC Plant Biol , IF:4.215 , 2022 Aug , V22 (1) : P415 doi: 10.1186/s12870-022-03801-8
Full-length transcriptome-referenced analysis reveals crucial roles of hormone and wounding during induction of aerial bulbils in lily.
Key Laboratory of Plant Resources and China National Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Beijing, Xiangshan, 100093, China.; Key Laboratory of Plant Resources and China National Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Beijing, Xiangshan, 100093, China. shilei_67@126.com.
Aerial bulbils are important vegetative reproductive organs in Lilium. They are often perpetually dormant in most Lilium species, and little is known about the induction of these vegetative structures. The world-famous Oriental hybrid lily cultivar 'Sorbonne', which blooms naturally devoid of aerial bulbils, is known for its lovely appearance and sweet fragrance. We found that decapitation stimulated the outgrowth of aerial bulbils at lower stems (LSs) and then application of low and high concentrations of IAA promoted aerial bulbils emergence around the wound at upper stems (USs) of 'Sorbonne'. However, the genetic basis of aerial bulbil induction is still unclear. Herein, 'Sorbonne' transcriptome has been sequenced for the first time using the combination of third-generation long-read and next-generation short-read technology. A total of 46,557 high-quality non-redundant full-length transcripts were generated. Transcriptomic profiling was performed on seven tissues and stems with treatments of decapitation and application of low and high concentrations of IAA, respectively. Functional annotation of 1918 DEGs within stem samples of different treatments showed that hormone signaling, sugar metabolism and wound-induced genes were crucial to bulbils outgrowth. The expression pattern of auxin-, shoot branching hormone-, plant defense hormone- and wound-inducing-related genes indicated their crucial roles in bulbil induction. Then we established five hormone- and wounding-regulated co-expression modules and identified some candidate transcriptional factors, such as MYB, bZIP, and bHLH, that may function in inducing bulbils. High connectivity was observed among hormone signaling genes, wound-induced genes, and some transcriptional factors, suggesting wound- and hormone-invoked signals exhibit extensive cross-talk and regulate bulbil initiation-associated genes via multilayered regulatory cascades. We propose that the induction of aerial bulbils at LSs after decapitation can be explained as the release of apical dominance. In contrast, the induction of aerial bulbils at the cut surface of USs after IAA application occurs via a process similar to callus formation. This study provides abundant candidate genes that will deepen our understanding of the regulation of bulbil outgrowth, paving the way for further molecular breeding of lily.
PMID: 36030206
BMC Plant Biol , IF:4.215 , 2022 Aug , V22 (1) : P389 doi: 10.1186/s12870-022-03778-4
The effect of DC electric field on the elongation growth, proton extrusion and membrane potential of Zea mays L. coleoptile cells; a laboratory study.
Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia in Katowice, 28 Jagiellonska St, 40-032, Katowice, Poland. waldemar.karcz@us.edu.pl.; Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia in Katowice, 28 Jagiellonska St, 40-032, Katowice, Poland.
BACKGROUND: In this study, we investigated the effect of an electric field, with an intensity similar to that of the Earth's field, on plant cells growth. The molecular mechanism underlying this effect remains unclear. RESULTS: It was found that the electric field, depending on the applied voltage, its duration and the polarization of the maize seedlings, stimulated or inhibited the growth of the seedling organs (root, mesocotyl and coleoptile). Moreover, it was also noticed that the gravitropic response of maize seedlings was inhibited at all voltages studied. Simultaneous measurements of growth and external medium pH show that auxin(IAA, indole-3-acetic acid)- and fusicoccin(FC)-induced elongation growth and proton extrusion of maize coleoptile segments were significantly inhibited at higher voltages. The ionic current flowing through the single coleoptile segment during voltage application was 1.7-fold lower in segments treated with cation channel blocker tetraethylammonium chloride (TEA-Cl) and 1.4-fold higher with IAA compared to the control. The electrophysiological experiments show that the electric field caused the depolarization of the membrane potential of parenchymal coleoptile cells, which was not reversible over 120 min. CONCLUSION: It is suggested that a DC electric field inhibits the plasma membrane H(+) pump activity and K(+) uptake through voltage-dependent, inwardly rectifying ZMK1 channels (Zea mays K(+) channel 1). The data presented here are discussed, taking into account the "acid growth hypothesis" of the auxin action and the mechanism of gravitropic response induction.
PMID: 35922781
Tree Physiol , IF:4.196 , 2022 Aug doi: 10.1093/treephys/tpac073
A genotype-specific architectural and physiological profile is involved in the flowering regularity of apple trees.
AGAP Institut, Univ Montpellier, CIRAD, INRAE, Institut Agro, 34398 Montpellier Cedex 5, France.; ITK, Clapiers, France.
In polycarpic plants, meristem fate varies within individuals in a given year. In perennials, the proportion of floral induction (FI) in meristems also varies between consecutive years and among genotypes of a given species. Previous studies have suggested that FI of meristems could be determined by the within plant competition for carbohydrates and by hormone signaling as key components of the flowering pathway. At the genotypic level, variability in FI was also associated with variability in architectural traits. However, the part of genotype-depended variability in FI that can be explained by either tree architecture or tree physiology is still not fully understood. This study aimed at deciphering the respective effect of architectural and physiological traits on FI variability within apple trees by comparing six genotypes with contrasted architectures. Shoot type demography as well as the flowering and fruit production patterns were followed over six years and characterized by different indexes. Architectural morphotypes were then defined based on architectural traits using a clustering approach. For two successive years, non-structural starch content in leaf, stem and meristems and hormonal contents (gibberellins, cytokinins, auxin and abscisic acid) in meristems were quantified and correlated to FI within-tree proportions. Based on a multi-step regression analysis, cytokinins and gibberellins content in meristem, starch content in leaves and the proportion of long shoots in tree annual growth were shown to contribute to FI. Although the predictive linear model of FI was common to all genotypes, each of the explicative variables had a different weight in FI determination, depending on the genotype. Our results therefore suggest both a common determination model and a genotype-specific architectural and physiological profile linked to its flowering behavior.
PMID: 35951430
Mol Plant Microbe Interact , IF:4.171 , 2022 Sep : PMPMI05220113TA doi: 10.1094/MPMI-05-22-0113-TA
Berberine Bridge Enzyme-like Oligosaccharide Oxidases Act as Enzymatic Transducers Between Microbial Glycoside Hydrolases and Plant Peroxidases.
Department of Life, Health and Environmental Sciences, University of L'Aquila, 67100 L'Aquila, Italy.; Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, 00185 Rome, Italy.
Oligogalacturonide (OG)-oxidase 1 (OGOX1) and cellodextrin (CD)-oxidase (CELLOX) are plant berberine bridge enzyme-like oligosaccharide oxidases that oxidize OGs and CDs, cell-wall fragments with the nature of damage-associated molecular patterns. The oxidation of OGs and CDs attenuates their elicitor activity and concomitantly releases H2O2. By using a multiple enzyme-based assay, we demonstrate that the H2O2 generated downstream of the combined action between a fungal polygalacturonase and OGOX1 or an endoglucanase and CELLOX can be directed by plant peroxidases (PODs) either towards a reaction possibly involved in plant defense, such as the oxidation of monolignol or a reaction possibly involved in a developmental event, such as the oxidation of auxin (indole-3-acetic acid), pointing to OGOX1 and CELLOX as enzymatic transducers between microbial glycoside hydrolases and plant PODs. [Formula: see text] Copyright (c) 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
PMID: 35704684
Microorganisms , IF:4.128 , 2022 Sep , V10 (9) doi: 10.3390/microorganisms10091802
The Metabolic Potential of Endophytic Actinobacteria Associated with Medicinal Plant Thymus roseus as a Plant-Growth Stimulator.
State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China.; Department of Biological, Marine Sciences and Environmental Agriculture, Institute for Post Graduate Environmental Studies, Arish University, Al-Arish 45511, Egypt.; Department of Environmental Protection, Faculty of Environmental Agricultural Sciences, Arish University, Al-Arish 45511, Egypt.; Faculty of Biology, National University of Uzbekistan, Tashkent 100174, Uzbekistan.; Institute of Fundamental and Applied Research, National Research University (TIIAME), Tashkent 100000, Uzbekistan.; Faculty of Organic Agriculture, Heliopolis University, Cairo 2834, Egypt.; State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China.; State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
Bio-fertilizer practice considers not only economical but also environmentally friendly, sustainable agriculture. Endophytes can play important beneficiary roles in plant development, directly, indirectly, or synergistically. In this study, the majority of our endophytic actinobacteria were able to possess direct plant growth-promoting (PGP) traits, including auxin (88%), ammonia (96%), siderophore production (94%), and phosphate solubilization (24%), along with cell-wall degrading enzymes such as protease (75%), cellulase (81%), lipase (81%), and chitinase (18%). About 45% of tested strains have an inhibitory effect on the phytopathogen Fusarium oxysporum, followed by 26% for Verticillium dahlia. Overall, our results showed that strains XIEG63 and XIEG55 were the potent strains with various PGP traits that caused a higher significant increase (p
PMID: 36144404
Genes (Basel) , IF:4.096 , 2022 Sep , V13 (9) doi: 10.3390/genes13091577
Comprehensive In Silico Characterization and Expression Pro-Filing of DA1/DAR Family Genes in Brassica rapa.
State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China.
The DA1/DAR family genes have been shown to play important roles in regulating organ size and plant biomass in the model plant Arabidopsis and several crops. However, this family has not been characterized in Brassica rapa (B. rapa). In this study, we identified 17 DA1&DAR genes from B. rapa. Phylogenetic analysis indicated that these genes are classified into four groups. Structural and motif analysis of BrDA1&DARs discovered that the genes within the same group have similar exon-intron structures and share an equal number of conserved motifs except for BrDAR6.3 from group IV, which contains two conserved motifs. Cis-regulatory elements identified four phytohormones (Salicylic acid, Abscisic acid, Gibberellin, and auxin) and three major abiotic (Light, Low temperature, and drought) responsive elements. Further, six br-miRNAs named br-miR164a, br-miR164b, br-miR164c, br-miR164d, br-miRN360, and br-miRN366 were found which target BrDAR6.1, BrDA1.4, and BrDA1.5. BrDA1&DAR genes were highly expressed in stem, root, silique, flower, leaf, and callus tissues. Moreover, qRT-PCR analyses indicated that some of these genes were responsive to abiotic stresses or phytohormone treatments. Our findings provide a foundation for further genetic and physiological studies of BrDA1&DARs in B. rapa.
PMID: 36140744
Plant Mol Biol , IF:4.076 , 2022 Sep doi: 10.1007/s11103-022-01308-2
The involvement of AtMKK1 and AtMKK3 in plant-deleterious microbial volatile compounds-induced defense responses.
Graduate Program in Translational Agricultural Sciences, National Cheng Kung University and Academia Sinica, Tainan, Taiwan.; Institute of Tropical Plant Sciences and Microbiology, National Cheng Kung University, Tainan, Taiwan.; Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan.; Department of Plant Systems Physiology, Radboud University, Nijmegen, The Netherlands.; Kaohsiung District Agricultural Research and Extension Station, Pingtung, Taiwan.; Graduate Program in Translational Agricultural Sciences, National Cheng Kung University and Academia Sinica, Tainan, Taiwan. haojen@mail.ncku.edu.tw.; Institute of Tropical Plant Sciences and Microbiology, National Cheng Kung University, Tainan, Taiwan. haojen@mail.ncku.edu.tw.; Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan. haojen@mail.ncku.edu.tw.
KEY MESSAGE: Plant-deleterious microbial volatiles activate the transactivation of hypoxia, MAMPs and wound responsive genes in Arabidopsis thaliana. AtMKK1 and AtMKK3 are involved in the plant-deleterious microbial volatiles-induced defense responses. Microbial volatile compounds (mVCs) are a collection of volatile metabolites from microorganisms with biological effects on all living organisms. mVCs function as gaseous modulators of plant growth and plant health. In this study, the defense events induced by plant-deleterious mVCs were investigated. Enterobacter aerogenes VCs lead to growth inhibition and immune responses in Arabidopsis thaliana. E. aerogenes VCs negatively regulate auxin response and transport gene expression in the root tip, as evidenced by decreased expression of DR5::GFP, PIN3::PIN3-GFP and PIN4::PIN4-GFP. Data from transcriptional analysis suggests that E. aerogenes VCs trigger hypoxia response, innate immune responses and metabolic processes. In addition, the transcript levels of the genes involved in the synthetic pathways of antimicrobial metabolites camalexin and coumarin are increased after the E. aerogenes VCs exposure. Moreover, we demonstrate that MKK1 serves as a regulator of camalexin biosynthesis gene expression in response to E. aerogenes VCs, while MKK3 is the regulator of coumarin biosynthesis gene expression. Additionally, MKK1 and MKK3 mediate the E. aerogenes VCs-induced callose deposition. Collectively, these studies provide molecular insights into immune responses by plant-deleterious mVCs.
PMID: 36109466
Plant Mol Biol , IF:4.076 , 2022 Aug doi: 10.1007/s11103-022-01304-6
Combined analysis of mRNA and miRNA reveals the banana potassium absorption regulatory network and validation of miRNA160a.
Institute of Horticulture Science and Engineering, Huaqiao University, Xiamen, 361021, China.; Institute of Fruit Tree ResearchKey Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization, Ministry of Agriculture and Rural AffairsGuangdong Provincial Key Laboratory of Tropical and Subtropical Fruit Tree Research, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China.; School of Agriculture and Environment, The UWA Institute of Agriculture, The University of Western Australia, Perth, 6009 WA, Australia.; Institute of Horticulture Science and Engineering, Huaqiao University, Xiamen, 361021, China. w_mingyuan@163.com.; Institute of Horticulture Science and Engineering, Huaqiao University, Xiamen, 361021, China. 907153549@qq.com.; Institute of Horticulture Science and Engineering, Huaqiao University, Xiamen, 361021, China. yuhailing1989@163.com.
Potassium (K) has an important effect on the growth and development of plants. Banana contains higher K content than many other fruits, and its plant requires more K nutrient in soil. However, the soil in the banana-producing areas in China is generally deficient in K. Therefore, understanding the mechanism of banana K absorption may assist in providing effective strategy to solve this problem. This study used two banana varieties with contrasting K tolerance, 'Guijiao No. 1' (low-K tolerant), and 'Brazilian banana' (low-K sensitive)to investigate K absorption mechanisms in response to low-K stress through miRNA and mRNA sequencing analysis. Under low-K condition, 'Guijiao No.1' showed higher plant height, dry weight, tissue K content and ATPase activity. Analysis of transcription factors showed that they were mainly in the types or classes of MYB, AP-EREBP, bHLH, etc. The sequencing results showed that 'Guijiao No. 1' had 776 differentially expressed genes (DEGs) and 27 differentially expressed miRNAs (DEMs), and 'Brazilian banana' had 71 DEGs and 14 DEMs between normal and low K treatments. RT-qPCR results showed that all miRNAs and mRNAs showed similar expression patterns with RNA-Seq and transcriptome. miRNA regulatory network was constructed by integrated analysis of miRNA-mRNA data. miR160a was screened out as a key miRNA, and preliminary functional validation was performed. Arabidopsis overexpressing miR160a showed reduced tolerance to low K, and inhibited phenotypic traits such as shorter root length, and reduced K accumulation. The overexpressed miR160a had a targeting relationship with ARF10 and ARF16 in Arabidopsis. These results indicate that miR160a may regulate K absorption in bananas through the auxin pathway. This study provides a theoretical basis for further study on the molecular mechanism of banana response to low potassium stress.
PMID: 35962899
Plant Mol Biol , IF:4.076 , 2022 Sep , V110 (1-2) : P107-130 doi: 10.1007/s11103-022-01289-2
The interaction between exogenous IBA with sucrose, light and ventilation alters the expression of ARFs and Aux/IAA genes in Carica papaya plantlets.
Centro de Investigacion Cientifica de Yucatan A.C., Calle 43 No. 130, Colonia Chuburna de Hidalgo, C.P. 97205, Merida, Yucatan, Mexico. estrella.humberto@inifap.gob.mx.; Instituto Nacional de Investigaciones Forestales, Agricolas y Pecuarias (INIFAP), Campo Experimental Ixtacuaco, Km 4.5 Carretera Martinez de la Torre-Tlapacoyan, C.P. 93600, Tlapacoyan, Veracruz, Mexico. estrella.humberto@inifap.gob.mx.; Centro de Investigacion Cientifica de Yucatan A.C., Calle 43 No. 130, Colonia Chuburna de Hidalgo, C.P. 97205, Merida, Yucatan, Mexico.; Independent Researcher, Calle 6a 279 a, Jardines de Vista Alegre, Merida, Yucatan, Mexico.; Institute of Nutrition and Functional Foods (INAF), Laval University, 2440 Boulevard Hochelaga, Quebec City, QC, G1V 0A6, Canada.; Centro de Investigacion Cientifica de Yucatan A.C., Calle 43 No. 130, Colonia Chuburna de Hidalgo, C.P. 97205, Merida, Yucatan, Mexico. jorgesm@cicy.mx.
KEY MESSAGE: The interaction between exogenous IBA with sucrose, light and ventilation, alters the expression of ARFs and Aux/IAA genes in in vitro grown Carica papaya plantlets. In vitro papaya plantlets normally show low rooting percentages during their ex vitro establishment that eventually leads to high mortality when transferred to field conditions. Indole-3-butyric acid (IBA) auxin is normally added to culture medium, to achieve adventitious root formation on in vitro papaya plantlets. However, the molecular mechanisms occurring when IBA is added to the medium under varying external conditions of sugar, light and ventilation have not been studied. Auxin response factors (ARF) are auxin-transcription activators, while auxin/indole-3-acetic acid (Aux/IAA) are auxin-transcription repressors, that modulate key components involved in auxin signaling in plants. In the present study, we identified 12 CpARF and 18 CpAux/IAA sequences in the papaya genome. The cis-acting regulatory elements associated to those CpARFs and CpAux/IAA gene families were associated with stress and hormone responses. Furthermore, a comprehensive characterization and expression profiling analysis was performed on 6 genes involved in rhizogenesis formation (CpARF5, 6, 7 and CpAux/IAA11, 13, 14) from in vitro papaya plantlets exposed to different rhizogenesis-inducing treatments. In general, intact in vitro plantlets were not able to produce adventitious roots, when IBA (2 mg L(-1)) was added to the culture medium; they became capable to produce roots and increased their ex-vitro survival. However, the best rooting and survival % were obtained when IBA was added in combination with adequate sucrose supply (20 g L(-1)), increased light intensity (750 micromol photon m(-2) s(-1)) and ventilation systems within the culture vessel. Interestingly, it was precisely under those conditions that promoted high rooting and survival %, where the highest expression of CpARFs, but the lowest expression of CpAux/IAAs occurred. One interesting case occurred when in vitro plantlets were exposed to high levels of light in the absence of added IBA, as high rooting and survival occurred, even though no exogenous auxin was added. In fact, plantlets from this treatment showed the right expression profile between auxin activators/repressors genes, in both stem base and root tissues.
PMID: 35725838
BMC Genomics , IF:3.969 , 2022 Sep , V23 (1) : P655 doi: 10.1186/s12864-022-08870-5
Transcriptome analysis of sweet potato responses to potassium deficiency.
Environment-friendly Crop Germplasm Innovation and Genetic Improvement Key Laboratory of Sichuan Province, Crop Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, 610066, Sichuan, China. wangfangsaas@126.com.; Environment-friendly Crop Germplasm Innovation and Genetic Improvement Key Laboratory of Sichuan Province, Crop Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, 610066, Sichuan, China.
BACKGROUND: As one of three essential nutrients, potassium is regarded as a main limiting factor for growth and development in plant. Sweet potato (Ipomoea batatas L.) is one of seven major food crops grown worldwide, and is both a nutrient-rich food and a bioenergy crop. It is a typical 'K-favoring' crop, and the level of potassium ion (K(+)) supplementation directly influences its production. However, little is known about the transcriptional changes in sweet potato genes under low-K(+) conditions. Here, we analyzed the transcriptomic profiles of sweet potato roots in response to K(+) deficiency to determine the effect of low-K(+) stress on this economically important crop. RESULTS: The roots of sweet potato seedlings with or without K(+) treatment were harvested and used for transcriptome analyses. The results showed 559 differently expressed genes (DEGs) in low and high K(+) groups. Among the DEGs, 336 were upregulated and 223 were downregulated. These DEGs were involved in transcriptional regulation, calcium binding, redox-signaling, biosynthesis, transport, and metabolic process. Further analysis revealed previously unknow genes involved in low-K(+) stress, which could be investigated further to improve low K(+) tolerance in plants. Confirmation of RNA-sequencing results using qRT-PCR displayed a high level of consistency between the two experiments. Analysis showed that many auxin-, ethylene- and jasmonic acid-related genes respond to K(+) deficiency, suggesting that these hormones have important roles in K(+) nutrient signaling in sweet potato. CONCLUSIONS: According to the transcriptome data of sweet potato, various DEGs showed transcriptional changes in response to low-K(+) stress. However, the expression level of some kinases, transporters, transcription factors (TFs), hormone-related genes, and plant defense-related genes changed significantly, suggesting that they have important roles during K(+) deficiency. Thus, this study identifies potential genes for genetic improvement of responses to low-K(+) stress and provides valuable insight into the molecular mechanisms regulating low K(+) tolerance in sweet potato. Further research is required to clarify the function of these DEGs under low-K(+) stress.
PMID: 36109727
BMC Genomics , IF:3.969 , 2022 Sep , V23 (1) : P638 doi: 10.1186/s12864-022-08864-3
Identification and characterization of miRNAs and PHAS loci related to the early development of the embryo and endosperm in Fragaria x ananassa.
Laboratory of Fruit Crop Biotechnology, College of Horticulture, Nanjing Agricultural University, No. 1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China.; Laboratory of Fruit Crop Biotechnology, College of Horticulture, Nanjing Agricultural University, No. 1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China. qiaoyushan@njau.edu.cn.
BACKGROUND: The strawberry fleshy fruit is actually enlarged receptacle tissue, and the successful development of the embryo and endosperm is essential for receptacle fruit set. MicroRNAs (miRNAs) and phased small interfering RNAs (phasiRNAs) play indispensable regulatory roles in plant growth and development. However, miRNAs and phasiRNAs participating in the regulation of strawberry embryo and endosperm development have yet to be explored. RESULTS: Here, we performed genome-wide identification of miRNA and phasiRNA-producing loci (PHAS) in strawberry seeds with a focus on those involved in the development of the early embryo and endosperm. We found that embryos and endosperm have different levels of small RNAs. After bioinformatics analysis, the results showed that a total of 404 miRNAs (352 known and 52 novel) and 156 PHAS genes (81 21-nt and 75 24-nt genes) could be found in strawberry seed-related tissues, of which four and nine conserved miRNA families displayed conserved expression in the endosperm and embryo, respectively. Based on refined putative annotation of PHAS loci, some auxin signal-related genes, such as CM3, TAR2, AFB2, ASA1, NAC and TAS3, were found, which demonstrates that IAA biosynthesis is important for endosperm and embryo development during early fruit growth. Additionally, some auxin signal-related conserved (miR390-TAS3) and novel (miR156-ASA1) trigger-PHAS pairs were identified. CONCLUSIONS: Taken together, these results expand our understanding of sRNAs in strawberry embryo and endosperm development and provide a genomic resource for early-stage fruit development.
PMID: 36076187
Pestic Biochem Physiol , IF:3.963 , 2022 Oct , V187 : P105211 doi: 10.1016/j.pestbp.2022.105211
Multiple resistance mechanisms to penoxsulam in Echinochloa crus-galli from China.
Department of Plant Protection, College of Plant Sciences & Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China.; General Station of Plant Protection, Hubei Province, Wuhan 430070, Hubei, PR China.; General Station of Plant Protection, Hubei Province, Wuhan 430070, Hubei, PR China. Electronic address: 897015023@qq.com.; Department of Plant Protection, College of Plant Sciences & Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China. Electronic address: mahongju@mail.hzau.edu.cn.
Penoxsulam is an important herbicide for the control of Echinochloa crus-galli (L.) P. Beauv. Two resistant populations 17GA (R1) and 16NXB (R2) showed 17- and 3-fold resistance to penoxsulam, respectively. A known resistance mutation of Trp-574-Leu in ALS gene and enhanced rates of penoxsulam metabolism likely involving GST contribute to penoxsulam resistance in R1 population. This population had resistance to the ALS-inhibitors pyribenzoxim and bispyribacsodium and the auxin herbicide quinclorac, but was susceptible to ACCase-inhibitors quizalofop-p-ethyl and cyhalofop-butyl. No known mutations in the ALS gene conferring target site resistance to ALS-inhibiting herbicides were presented in R2 population. However, penoxsulam metabolism in R2 plants was about 4-fold greater than in susceptible population 14YC (S0) plants. The enzyme inhibitors piperonyl butoxide, malathion and 4-chloro-7-nitrobenzoxadiazole reversed penoxsulam resistance in this population. GST and P450 enzyme activities and the genes of GST1-1, GST1-2, GST1-3, CYP81A18, CYP81A12, CYP81A21 were increased significantly in R2 population. These results indicate that multiple resistance mechanisms had occurred in E. crus-galli populations in central China and resistance needs to be managed effectively by diverse chemical and non-chemical methods.
PMID: 36127055
Plants (Basel) , IF:3.935 , 2022 Sep , V11 (18) doi: 10.3390/plants11182400
Dynamic RNA-Seq Study Reveals the Potential Regulators of Seed Germination in Paris polyphylla var. yunnanensis.
The Laboratory of Seed Science and Technology, Guangdong Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou 510642, China.; Guangzhou Key Laboratory for Research and Development of Crop Germplasm Resources, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China.; College of Traditional Chinese Medicine, Yunnan University of Chinese Medicine, Kunming 650500, China.
Paris polyphylla var. yunnanensis is an important traditional Chinese medicine, but poor seed germination limits its large-scale artificial cultivation. Thus, it is crucial to understand the regulators of seed germination to obtain clues about how to improve the artificial cultivation of Paris polyphylla. In this study, the seeds at three germination stages, including ungerminated seeds (stage 1), germinated seeds with a 0.5 cm radicel length (stage 2), and germinated seeds with a 2.0 cm radicel length (stage 3) after warm stratification (20 degrees C) for 90 days were used for RNA sequencing. Approximately 220 million clean reads and 447,314 annotated unigenes were obtained during seed germination, of which a total of 4454, 5150, and 1770 differentially expressed genes (DEGs) were identified at stage 1 to stage 2, stage 1 to stage 3, and stage 2 to stage 3, respectively. Encyclopedia of Genes and Genomes (KEGG) analysis revealed that the DEGs were significantly enriched in carbohydrate metabolism, lipid metabolism, signal transduction, and translation. Of them, several genes encoding the glutamate decarboxylase, glutamine synthetase, alpha-galactosidase, auxin-responsive protein IAA30, abscisic-acid-responsive element binding factor, mitogen-activated protein kinase kinase 9/18, and small and large subunit ribosomal proteins were identified as potentially involved in seed germination. The identified genes provide a valuable resource to study the molecular basis of seed germination in Paris polyphylla var. yunnanensis.
PMID: 36145801
Plants (Basel) , IF:3.935 , 2022 Sep , V11 (18) doi: 10.3390/plants11182344
Crosstalk of Cytokinin with Ethylene and Auxin for Cell Elongation Inhibition and Boron Transport in Arabidopsis Primary Root under Boron Deficiency.
Departamento de Fisiologia, Anatomia y Biologia Celular, Universidad Pablo de Olavide, E-41013 Sevilla, Spain.
Several studies have shown the role of phytohormones in the regulation of root growth of Arabidopsis plants under boron (B) deficiency. Ethylene and auxin play an important role in the control of Arabidopsis primary root cell elongation under short-term B deprivation, whereas cytokinins regulate root growth inhibition under B deficiency by controlling meristem cell proliferation. In this work, we study the possible interaction among cytokinin, ethylene, and auxin in the primary root response to B-deprivation treatment, as well as their possible role in B uptake and transport. Wild type (WT) and two mutants related to auxin and ethylene (aux1 and acs11) Arabidopsis plants were grown in control (10 microM B) or B starvation (0 microM B) treatment, in the absence or presence of trans-zeatin, and their primary root growth was analyzed. The possible interaction between these hormones was also studied by analyzing AUX1 gene expression in the acs11 mutant and ACS11 gene expression in the aux1 mutant. The GUS reporter lines ARR5::GUS, IAA2::GUS, and EBS::GUS were used to observe changes in cytokinin, auxin, and ethylene levels in the root, respectively. The results of this work suggest that cytokinin inhibits root cell elongation under B deficiency through two different mechanisms: (i) an ethylene-dependent mechanism through increased expression of the ACS11 gene, which would lead to increased ethylene in the root, and (ii) an ethylene-independent mechanism through decreased expression of the AUX1 gene, which alters auxin signaling in the meristematic and elongation zones and stele. We also report that changes in the expression of several B transporters occur in response to auxin, ethylene, and cytokinin that may affect the plant B content.
PMID: 36145745
Plants (Basel) , IF:3.935 , 2022 Sep , V11 (17) doi: 10.3390/plants11172324
Identification of QTL under Brassinosteroid-Combined Cold Treatment at Seedling Stage in Rice Using Genotyping-by-Sequencing (GBS).
Key Laboratory of Agricultural Biotechnology of Liaoning Province, College of Biosciences and Biotechnology, Shenyang Agricultural University, Shenyang 110866, China.; Rice Research Institute, College of Agronomy, Shenyang Agricultural University, Shenyang 110866, China.; Rice Research Institute, Jiangxi Academy of Agricultural Sciences, Nanchang 330200, China.; Department of Agronomy, College of Agriculture, Purdue University, West Lafayette, IN 47907, USA.
Cold stress is a major threat to the sustainability of rice yield. Brassinosteroids (BR) application can enhance cold tolerance in rice. However, the regulatory mechanism related to cold tolerance and the BR signaling pathway in rice has not been clarified. In the current study, the seedling shoot length (SSL), seedling root length (SRL), seedling dry weight (SDW), and seedling wet weight (SWW) were used as the indices for identifying cold tolerance under cold stress and BR-combined cold treatment in a backcross recombinant inbred lines (BRIL) population. According to the phenotypic characterization for cold tolerance and a high-resolution SNP genetic map obtained from the GBS technique, a total of 114 QTLs were identified, of which 27 QTLs were detected under cold stress and 87 QTLs under BR-combined cold treatment. Among them, the intervals of many QTLs were coincident under different treatments, as well as different traits. A total of 13 candidate genes associated with cold tolerance or BR pathway, such as BRASSINAZOLE RESISTANT1 (OsBZR1), OsWRKY77, AP2 domain-containing protein, zinc finger proteins, basic helix-loop-helix (bHLH) protein, and auxin-induced protein, were predicted. Among these, the expression levels of 10 candidate genes were identified under different treatments in the parents and representative BRIL individuals. These results were helpful in understanding the regulation relationship between cold tolerance and BR pathway in rice.
PMID: 36079705
Plants (Basel) , IF:3.935 , 2022 Aug , V11 (17) doi: 10.3390/plants11172282
Effects of Different Drought Degrees on Physiological Characteristics and Endogenous Hormones of Soybean.
Agricultural College, Northeast Agricultural University, Harbin 150030, China.; Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Drought affects crop developmentnand growth. To explore the physiological effects of drought stress on soybean, HeiNong44 (HN44) and HeiNong65 (HN65) varieties were used as experimental materials and PEG-6000 was used as the osmotic medium. The antioxidant enzyme activity, osmotic adjustment substance content, antioxidant capacity, and endogenous hormone content of the two soybean varieties were studied under different drought degrees and different treatment durations. Drought stress caused significant physiological changes in soybean. The antioxidant enzyme activities, osmoregulation substance content, and total antioxidant capacity (T-AOC) of HN65 and HN44 showed an increasing trend under mild and moderate drought, however, they first increased and then decreased under severe drought conditions. Following the extension of treatment time, malondialdehyde (MDA) showed an increasing trend. As drought increased, gibberellin (GA) content showed a decreasing trend, while abscisic acid (ABA), salicylic acid (SA), and zeatin nucleoside (ZA) content showed an increasing trend. The auxin (IAA) content of the two varieties showed opposite change trends. In short, drought had a significant impact on the physiology of these two soybean varieties; however, overall, the drought resistance of HN65 was lower than that of HN44. This study provides a research theoretical basis for addressing the drought resistance mechanism and the breeding of drought resistant soybean varieties.
PMID: 36079664
Plants (Basel) , IF:3.935 , 2022 Aug , V11 (17) doi: 10.3390/plants11172231
Draft Genome Sequence of Priestia sp. Strain TSO9, a Plant Growth-Promoting Bacterium Associated with Wheat (Triticum turgidum subsp. durum) in the Yaqui Valley, Mexico.
Instituto Tecnologico de Sonora, 5 de Febrero 818 sur, Ciudad Obregon 85000, Sonora, Mexico.; Department of Microbiology, Raiganj University, Raiganj 733 134, Uttar Dinajpur, West Bengal India, India.; Department of Botany, Government College Women University Sialkot, Sialkot 51310, Pakistan.; Agricultural Botany Department, Faculty of Agriculture, Tanta University, Tanta 31527, Egypt.; Campo Experimental Norman E. Borlaug, Instituto Nacional de Investigaciones Forestales, Agricolas y Pecuarias, Ciudad Obregon 85000, Sonora, Mexico.
Strain TSO9 was isolated from a commercial field of wheat (Triticum turgidum L. subsp. durum) located in the Yaqui, Valley, Mexico. Here, the genome of this strain was sequenced, obtaining a total of 5,248,515 bp; 38.0% G + C content; 1,186,514 bp N50; and 2 L50. Based on the 16S rRNA gene sequencing, strain TSO9 was affiliated with the genus Priestia. The genome annotation of Priestia sp. TSO9 contains a total of 147 RNAs, 128 tRNAs, 1 tmRNA, and 5512 coding DNA sequences (CDS) distributed into 332 subsystems, where CDS associated with agricultural purposes were identified, such as (i) virulence, disease, and defense (57 CDS) (i.e., resistance to antibiotics and toxic compounds (34 CDS), invasion and intracellular resistance (12 CDS), and bacteriocins and ribosomally synthesized antibacterial peptides (10 CDS)), (ii) iron acquisition and metabolism (36 CDS), and (iii) secondary metabolism (4 CDS), i.e., auxin biosynthesis. In addition, subsystems related to the viability of an active ingredient for agricultural bioproducts were identified, such as (i) stress response (65 CDS). These genomic traits are correlated with the metabolic background of this strain, and its positive effects on wheat growth regulation reported in this work. Thus, further investigations of Priestia sp. TSO9 are necessary to complement findings regarding its application in agroecosystems to increase wheat yield sustainably.
PMID: 36079613
Plants (Basel) , IF:3.935 , 2022 Aug , V11 (16) doi: 10.3390/plants11162163
Transcriptomic Analysis of Radish (Raphanus sativus L.) Roots with CLE41 Overexpression.
Department of Genetics and Biotechnology, Saint Petersburg State University, 199034 Saint Petersburg, Russia.
The CLE41 peptide, like all other TRACHEARY ELEMENT DIFFERENTIATION INHIBITORY FACTOR (TDIF) family CLE peptides, promotes cell division in (pro-)cambium vascular meristem and prevents xylem differentiation. In this work, we analyzed the differential gene expression in the radish primary-growing P35S:RsCLE41-1 roots using the RNA-seq. Our analysis of transcriptomic data revealed a total of 62 differentially expressed genes between transgenic radish roots overexpressing the RsCLE41-1 gene and the glucuronidase (GUS) gene. For genes associated with late embryogenesis, response to abscisic acid and auxin-dependent xylem cell fate determination, an increase in the expression in P35S:RsCLE41-1 roots was found. Among those downregulated, stress-associated genes prevailed. Moreover, several genes involved in xylem specification were also downregulated in the roots with RsCLE41-1 overexpression. Unexpectedly, none of the well-known targets of TDIFs, such as WOX4 and WOX14, were identified as DEGs in our experiment. Herein, we discuss a suggestion that the activation of pathways associated with desiccation resistance, which are more characteristic of late embryogenesis, in roots with RsCLE41-overexpression may be a consequence of water deficiency onset due to impaired vascular specification.
PMID: 36015466
Plants (Basel) , IF:3.935 , 2022 Aug , V11 (16) doi: 10.3390/plants11162092
Systematic Analysis of the Grafting-Related Glucanase-Encoding GH9 Family Genes in Pepper, Tomato and Tobacco.
Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan 430070, China.; Shenzhen Institute of Nutrition and Health, Huazhong Agricultural University, Shenzhen 518120, China.; Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China.
Grafting is an important agricultural practice to control soil-borne diseases, alleviate continuous cropping problems and improve stress tolerance in vegetable industry, but it is relatively less applied in pepper production. A recent study has revealed the key roles of beta-1, 4-glucanase in graft survival. We speculated that the GH9 family gene encoding glucanase may be involved in the obstacles of pepper grafting. Therefore, we performed a systematic analysis of the GH9 family in pepper, tomato and tobacco. A total of 25, 24 and 42 GH9 genes were identified from these three species. Compared with the orthologues of other solanaceous crops, the deduced pepper GH9B3 protein lacks a conserved motif (Motif 5). Promoter cis-element analysis revealed that a wound-responsive element exists in the promoter of tobacco NbGH9B3, but it is absent in the GH9B3 promoter of most solanaceous crops. The auxin-responsive related element is absent in CaGH9B3 promoter, but it presents in the promoter of tobacco, tomato, potato and petunia GH9B3. Tissue and induction expression profiles indicated that GH9 family genes are functionally differentiated. Nine GH9 genes, including CaGH9B3, were detected expressing in pepper stem. The expression patterns of NbGH9B3 and CaGH9B3 in grafting were different in our test condition, with obvious induction in tobacco but repression in pepper. Furthermore, weighted correlation network analysis (WGCNA) revealed 58 transcription factor genes highly co-expressed with NbGH9B3. Eight WRKY binding sites were detected in the promoter of NbGH9B3, and several NbWRKYs were highly co-expressed with NbGH9B3. In conclusion, the missing of Motif 5 in CaGH9B3, and lacking of wound- and auxin-responsive elements in the gene promoter are the potential causes of grafting-related problems in pepper. WRKY family transcription factors could be important regulator of NbGH9B3 in tobacco grafting. Our analysis points out the putative regulators of NbGH9B3, which would be helpful to the functional validation and the study of signal pathways related to grafting in the future.
PMID: 36015396
Plants (Basel) , IF:3.935 , 2022 Aug , V11 (15) doi: 10.3390/plants11152013
Auxin-Cytokinin Cross Talk in Somatic Embryogenesis of Coffea canephora.
Unidad de Bioquimica y Biologia Molecular de Plantas, Centro de Investigacion Cientifica de Yucatan, Calle 43, No. 130 x 32 y 34, Merida 97205, Mexico.; Catedratico CONACYT, Unidad de Bioquimica y Biologia Molecular de Plantas, Centro de Investigacion Cientifica de Yucatan, Merida 97205, Mexico.
Cytokinins (CK) are plant growth regulators involved in multiple physiological processes in plants. One less studied aspect is CK homeostasis (HM). The primary genes related to HM are involved in biosynthesis (IPT), degradation (CKX), and signaling (ARR). This paper demonstrates the effect of auxin (Aux) and CK and their cross talk in a Coffea canephora embryogenic system. The transcriptome and RT-qPCR suggest that Aux in pre-treatment represses biosynthesis, degradation, and signal CK genes. However, in the induction, there is an increase of genes implicated in the CK perception/signal, indicating perhaps, as in other species, Aux is repressing CK, and CK are inducing per se genes involved in its HM. This is reflected in the endogenous concentration of CK; pharmacology experiments helped study the effect of each plant growth regulator in our SE system. We conclude that the Aux-CK balance is crucial to directing somatic embryogenesis in C. canephora.
PMID: 35956493
Biosci Rep , IF:3.84 , 2022 Sep , V42 (9) doi: 10.1042/BSR20221504
Negative regulation of seed germination by maternal AFB1 and AFB5 in Arabidopsis.
Department of Plant Biology, Ecology, and Evolution, Oklahoma State University, 301 Physical Sciences, Stillwater, OK 74078, U.S.A.
The plant hormone auxin suppresses seed germination, but how auxin does it remains poorly understood. While studying the functions of the AUXIN SIGNALING F-BOX (AFB) auxin co-receptors in Arabidopsis, we consistently isolated AFB1 and AFB5 in reproductive tissues in co-immunoprecipitation experiments using their interacting protein ASK1 as the bait. However, T2 seeds of the AFB1 or AFB5 transgenic lines generated for the co-immunoprecipitation experiments frequently failed to germinate, which led to the studies of seed germination in these plants and afb1 and afb5 mutants, and AFB1 and AFB5 expression in nearly mature fruit and imbibed seeds using AFB1:GUS and AFB5:GUS lines. We found that AFB1 and AFB5 acted in maternal tissues to suppress seed germination and their effects were positively correlated with the plants' sensitivity to indole acetic acid. Conversely, afb1 and afb5 single mutants exhibited faster seed germination than the wild type and the seeds of the afb1-5afb5-5 double mutant germinated even faster than those of the afb1-5 and afb5-5 single mutants. Seed germination of the afb1-5afb5-5 double mutant also exhibited higher sensitivity to gibberellic acid than that of the wild-type and the afb1-3, afb1-5 and afb5-5 single mutants. Both AFB1 and AFB5 were expressed in the funiculus during seed maturation, and AFB1 was also transiently expressed in a small chalazal region surrounding the hilum in the seed coat during seed imbibition. Therefore, AFB1 and AFB5 likely suppress seed germination in the funiculus and AFB1 also briefly suppresses seed germination in the chalaza during seed imbibition.
PMID: 36039862
Life (Basel) , IF:3.817 , 2022 Aug , V12 (8) doi: 10.3390/life12081285
New Wine in an Old Bottle: Utilizing Chemical Genetics to Dissect Apical Hook Development.
Institute of Plant and Food Science, Department of Biology, School of Life Sciences, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China.; Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Southern University of Science and Technology, Shenzhen 518055, China.
The apical hook is formed by dicot seedlings to protect the tender shoot apical meristem during soil emergence. Regulated by many phytohormones, the apical hook has been taken as a model to study the crosstalk between individual signaling pathways. Over recent decades, the roles of different phytohormones and environmental signals in apical hook development have been illustrated. However, key regulators downstream of canonical hormone signaling have rarely been identified via classical genetics screening, possibly due to genetic redundancy and/or lethal mutation. Chemical genetics that utilize small molecules to perturb and elucidate biological processes could provide a complementary strategy to overcome the limitations in classical genetics. In this review, we summarize current progress in hormonal regulation of the apical hook, and previously reported chemical tools that could assist the understanding of this complex developmental process. We also provide insight into novel strategies for chemical screening and target identification, which could possibly lead to discoveries of new regulatory components in apical hook development, or unidentified signaling crosstalk that is overlooked by classical genetics screening.
PMID: 36013464
Life (Basel) , IF:3.817 , 2022 Aug , V12 (8) doi: 10.3390/life12081283
The Application of Auxin-like Compounds Promotes Cold Acclimation in the Oilseed Rape Plant.
Laboratory of Plant Physiology, Nature Research Centre, Akademijos Str. 2, 08412 Vilnius, Lithuania.
Cold is a major environmental key factor influencing plant growth, development, and productivity. Responses and adaption processes depend on plant physiological and biochemical modifications, first of all via the hormonal system. Indole-3-acetic acid (IAA) plays a critical role in the processes of plant functioning. To assess the influence of the auxin-like compounds 1-[2-chloroethoxycarbonylmethyl]-4-naphthalenesulfonic acid calcium salt (TA-12) and 1-[2-dimethylaminoethoxycarbonylmethyl]naphthalene chloromethylate (TA-14) in the process of cold acclimation, long-term field trials over four years were performed with two rapeseed (Brassica napus L.) plant cultivars with different wintering resistance in temperate-zone countries. In these two rapeseed cultivars, namely 'Casino' (less resistant) and 'Valesca' (more resistant), investigations were conducted in the terminal buds and root collars. The application of auxin-like compounds revealed a close interlinkage between the composition of dehydrins and the participation of the phytohormone IAA in the adaptation processes. By applying TA-12 and TA-14, the importance of the proteins, especially the composition of the dehydrins, the IAA amount, and the status of the oilseed rape cultivars at the end of the cold acclimation period were confirmed. Following on from this, when introducing oilseed rape cultivars from foreign countries, it may also be of value to assess their suitability for cultivation in temperate-zone countries.
PMID: 36013462
Life (Basel) , IF:3.817 , 2022 Aug , V12 (8) doi: 10.3390/life12081260
Analysis of Floral Organ Development and Sex Determination in Schisandra chinensis by Scanning Electron Microscopy and RNA-Sequencing.
College of Chinese Medicine Materials, Jilin Agricultural University, Changchun 130118, China.; School of Life Sciences, Tonghua Normal University, Tonghua 134000, China.
S. chinensis is a typical monoecious plant, and the number and development of female flowers determines the yield of S. chinensis. Due to a lack of genetic information, the molecular mechanism of sex differentiation in S. chinensis remains unclear. In this study, the combination of scanning electron microscopy (SEM) and RNA sequencing (RNA-seq) was used to understand the way of sex differentiation of S. chinensis and to mine the related genes of sex determination. The result shows the development of male and female S. chinensis flowers was completed at the same time, the unisexual S. chinensis flowers did not undergo a transition stage between sexes, and sex may have been determined at an early stage in flower development. The results of the gene function analysis of the plant hormone signaling pathway and sucrose metabolism pathway suggest that auxin and JA could be the key hormones for sex differentiation in S. chinensis, and sucrose may promote pollen maturation at the later stage of male flower development. Two AGAMOUS (GAG) genes, 10 AGAMOUS-like MADS-box (AGLs) genes, and the MYB, NAC, WRKY, bHLH, and Trihelix transcription factor families may play important roles in sex determination in S. chinensis. Taken together, the present findings provide valuable genetic information on flower development and sex determination in S. chinensis.
PMID: 36013439
Life (Basel) , IF:3.817 , 2022 Aug , V12 (8) doi: 10.3390/life12081231
Effects of Different Growth Regulators on the Rooting of Catalpa bignonioides Softwood Cuttings.
College of Forest, Henan Agricultural University, Zhengzhou 450002, China.
(1) Background: To further improve the rapid reproduction and large-scale application of Catalpa bignonioides. (2) Methods: With young softwood cuttings from a 3-year-old C. bignonioides mother plant used as materials, the effects of indole-3-acetic acid(IAA), indolebutyric acid(IBA) and rhizogenic powder-1(ABT-1) growth regulators at different concentrations on cutting indexes and the dynamic changes in endogenous hormone contents during the rooting of the C. bignonioides cuttings were studied. (3) Results: The rooting of C. bignonioides cuttings could be divided into five stages. There were three types of rooting of adventitious roots. IBA treatment resulted in a high rooting rate and beneficial root morphology. The morphological indexes of the cutting roots after treatment with 1000 mg.L(-1) IBA had the best overall quality, which was significantly higher than that of the roots in the control (CK) group (p < 0.05). Although the average longest root length (20.51 cm) under ABT-1 was the longest, its overall average rooting rate was slightly lower than that under IBA. The rooting effect under IAA was generally lower than that under IBA and ABT-1. The endogenous hormone content of the cuttings was found to be closely related to rooting; the IAA and zeatin nucleoside (ZR) content was high, and the ratios of IAA/ABA and IAA/ZR were high. The contents of gibberellin3 (GA3) and abscisic acid (ABA) were low, which had a promoting effect on the rooting of the cuttings. (5) Conclusions: All three kinds of auxin can promote rooting and, of the three treatment groups, the rooting effect of cuttings in the IBA treatment group was the strongest, with 1000 mg.L(-1) being the optimum concentration.
PMID: 36013410
Gene , IF:3.688 , 2022 Aug , V837 : P146692 doi: 10.1016/j.gene.2022.146692
SAUR8, a small auxin-up RNA gene in poplar, confers drought tolerance to transgenic Arabidopsis plants.
Laboratory of Modern Biotechnology, School of Forestry and Landscape Architecture, Anhui Agricultural University, Hefei 230036, China.; Laboratory of Modern Biotechnology, School of Forestry and Landscape Architecture, Anhui Agricultural University, Hefei 230036, China. Electronic address: xiangyanahau@sina.com.
SAUR (small auxin-up RNA) is an early auxin-responsive gene. In this study, a novel SAUR gene PtSAUR8 was cloned from poplar (Populus trichocarpa), and subcellular location analysis showed that it is targeted to the nuclear membrane. In addition, PtSAUR8 overexpression in Arabidopsis improved the plant resistance to drought stress. Meanwhile, the loss of function mutant saur53 showed more drought sensitivity compared to the WT. PtSAUR8 conferred drought tolerance in transgenic Arabidopsis, as determined through phenotypic and stress-associated physiological indicator analyses, namely, root length, germination rate, relative water content, proline content, CAT content, POD content, malondialdehyde content, hydrogen peroxide content, and relative conductivity. In addition, after the 1 muM abscisic acid (ABA) treatment, the PtSAUR8-OE lines promoted stomata closure. Quantitative fluorescence analysis of related genes induced by drought mutant stress further confirmed that overexpression of PtSAUR8 can improve drought resistance in transgenic Arabidopsis lines. Therefore, PtSAUR8 may play a role in plant drought resistance through ABA-mediated pathways; thus, providing new research materials for molecular breeding of poplar resistance.
PMID: 35760288
J Plant Physiol , IF:3.549 , 2022 Oct , V277 : P153792 doi: 10.1016/j.jplph.2022.153792
Regulation of pollen tube growth by cellular pH and ions.
MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 73000, China. Electronic address: zhouzhg18@lzu.edu.cn.; College of Life Sciences, Northwest Normal University, Lanzhou, Gansu, 730070, China; Academy of Plateau Science and Sustainability, Qinghai Normal University, Xining, Qinghai, 810016, China.; MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 73000, China.; College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang, Guangdong, 524088, China.; MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 73000, China; Academy of Plateau Science and Sustainability, Qinghai Normal University, Xining, Qinghai, 810016, China; College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang, Guangdong, 524088, China. Electronic address: qiuqsh@lzu.edu.cn.
Tip growth of the pollen tube is a model system for the study of cell polarity establishment in flowering plants. The tip growth of the pollen tube displays an oscillating pattern corresponding to cellular ion and pH dynamics. Therefore, cellular pH and ions play an important role in pollen growth and development. In this review, we summarized the current advances in understanding the function of cellular pH and ions in regulating pollen tube growth. We analyzed the physiological roles and underlying mechanisms of cellular pH and ions, including Ca(2+), K(+), and Cl(-), in regulating pollen tube growth. We further examined the function of Ca(2+) in regulating cytoskeletons, small G proteins, and cell wall development in relation to pollen tube growth. We also examined the regulatory roles of cellular pH in pollen tube growth as well as pH regulation of ion flow, cell wall development, auxin signaling, and cytoskeleton function in pollen. In addition, we assessed the regulation of pollen tube growth by proton pumps and the maintenance of pH homeostasis in the trans-Golgi network by ion transporters. The interplay of ion homeostasis and pH dynamics was also assessed. We discussed the unanswered questions regarding pollen tube growth that need to be addressed in the future.
PMID: 35973258
Protoplasma , IF:3.356 , 2022 Sep doi: 10.1007/s00709-022-01808-4
Insights of auxin signaling F-box genes in wheat (Triticum aestivum L.) and their dynamic expression during the leaf rust infection.
Department of Bioengineering and Biotechnology, Birla Institute of Technology, Mesra, Ranchi, 835215, Jharkhand, India.; Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.; Department of Bioengineering and Biotechnology, Birla Institute of Technology, Mesra, Ranchi, 835215, Jharkhand, India. kmukhopadhyay@bitmesra.ac.in.
The TRANSPORT INHIBITOR RESPONSE 1/AUXIN SIGNALING F-BOX (TIR1/AFB) protein serves as auxin receptor and links with Aux/IAA repressor protein leading to its degradation via SKP-Cullin-F box (SCF(TIR1/AFB)) complex in the auxin signaling pathway. Present study revealed 11 TIR1/AFB genes in wheat by genome-wide search using AFB HMM profile. Phylogenetic analysis clustered these genes in two classes. Several phytohormone, abiotic, and biotic stress responsive cis-elements were detected in promoter regions of TIR1/AFB genes. These genes were localized on homoeologous chromosome groups 2, 3, and 5 showing orthologous relation with other monocot plants. Most genes were interrupted by introns and the gene products were localized in cytoplasm, nucleus, and cell organelles. TaAFB3, TaAFB5, and TaAFB8 had nuclear localization signals. The evolutionary constraint suggested paralogous sister pairs and orthologous genes went through strong purifying selection process and are slowly evolving at protein level. Functional annotation revealed all TaAFB genes participated in auxin activated signaling pathway and SCF-mediated ubiquitination process. Furthermore, in silico expression study revealed their diverse expression profiles during various developmental stages in different tissues and organs as well as during biotic and abiotic stress. QRT-PCR based studies suggested distinct expression pattern of TIR1-1, TIR1-3, TaAFB1, TaAFB2, TaAFB3, TaAFB4, TaAFB5, TaAFB7, and TaAFB8 displaying maximum expression at 24 and 48 h post inoculation in both susceptible and resistant near isogenic wheat lines infected with leaf rust pathogen. Importantly, this also reflects coordinated responses in expression patterns of wheat TIR1/AFB genes during progression stages of leaf rust infection.
PMID: 36100728
Protoplasma , IF:3.356 , 2022 Sep , V259 (5) : P1175-1188 doi: 10.1007/s00709-021-01732-z
The RNA polymerase II subunit NRPB2 is required for indeterminate root development, cell viability, stem cell niche maintenance, and de novo root tip regeneration in Arabidopsis.
Facultad de Quimico Farmacobiologia, Universidad Michoacana de San Nicolas de Hidalgo, Avenida Tzintzuntzan 173, Col. Matamoros, 58240, Morelia, Michoacan, Mexico. javier.raya@umich.mx.; Instituto de Investigaciones Quimico Biologicas, Universidad Michoacana de San Nicolas de Hidalgo, Edificio B3, Ciudad Universitaria, 58030, Morelia, Michoacan, Mexico.; Centro Multidisciplinario de Estudios en Biotecnologia, Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolas de Hidalgo, Morelia, Michoacan, Mexico.; Instituto de Investigaciones Quimico Biologicas, Universidad Michoacana de San Nicolas de Hidalgo, Edificio B3, Ciudad Universitaria, 58030, Morelia, Michoacan, Mexico. jbucio@umich.mx.
The RNA polymerase II drives the biogenesis of coding and non-coding RNAs for gene expression. Here, we describe new roles for its second-largest subunit, NRPB2, on root organogenesis and regeneration. Down-regulation of NRPB2 activates a determinate developmental program, which correlated with a reduction in mitotic activity, cell elongation, and size of the root apical meristem. Noteworthy, nrpb2-3 mutants manifest cell death in pro-vascular cells within primary root tips of plants grown in darkness or exposed to light, which triggers the expression of the regeneration gene marker ERF115 in neighbor cells close to damage. Auxin and stem cell niche (SCN) gene expression as well as structural analysis revealed that NRPB2 maintains SCN activity through distribution of PIN transporters in root tissues. Wild-type seedlings regenerated the root tip after excision of the QC and SCN, but nrpb2-3 mutants did not rebuild the missing tissues, and this process could be genotypified using pERF115:GFP, DR5:GFP, and pWOX5:GFP reporter constructs. The levels of reactive oxygen species increased in the mutants four days after germination and strongly decreased at later times, whereas nitric oxide accumulated as the root tip differentiates. These results show the importance of the transcriptional machinery for root organogenesis, cell viability, and regenerative capacity for reconstruction of tissues and organs upon injury.
PMID: 34981212
Protoplasma , IF:3.356 , 2022 Sep , V259 (5) : P1139-1155 doi: 10.1007/s00709-021-01724-z
Micrococcus luteus LS570 promotes root branching in Arabidopsis via decreasing apical dominance of the primary root and an enhanced auxin response.
Instituto de Investigaciones Quimico-Biologicas, Universidad Michoacana de San Nicolas de Hidalgo, Edificio B3, Ciudad Universitaria, C. P. 58030, Morelia, Michoacan, Mexico.; Catedratico CONACYT-Instituto de Ecologia A.C. Red de Estudios Moleculares Avanzados, Cluster BioMimic(R), Instituto de Ecologia A.C. Carretera Antigua a Coatepec, 351, El Haya, Xalapa, Veracruz, 91073, Mexico.; Instituto de Investigaciones Quimico-Biologicas, Universidad Michoacana de San Nicolas de Hidalgo, Edificio B3, Ciudad Universitaria, C. P. 58030, Morelia, Michoacan, Mexico. jbucio@umich.mx.
The interaction of plant roots with bacteria is influenced by chemical signaling, where auxins play a critical role. Auxins exert positive or negative influences on the plant traits responsible of root architecture configuration such as root elongation and branching and root hair formation, but how bacteria that modify the plant auxin response promote or repress growth, as well as root structure, remains unknown. Here, we isolated and identified via molecular and electronic microscopy analysis a Micrococcus luteus LS570 strain as a plant growth promoter that halts primary root elongation in Arabidopsis seedlings and strongly triggers root branching and absorptive potential. The root biomass was exacerbated following root contact with bacterial streaks, and this correlated with inducible expression of auxin-related gene markers DR5:GUS and DR5:GFP. Cellular and structural analyses of root growth zones indicated that the bacterium inhibits both cell division and elongation within primary root tips, disrupting apical dominance, and as a consequence differentiation programs at the pericycle and epidermis, respectively, triggers the formation of longer and denser lateral roots and root hairs. Using Arabidopsis mutants defective on auxin signaling elements, our study uncovers a critical role of the auxin response factors ARF7 and ARF19, and canonical auxin receptors in mediating both the primary root and lateral root response to M. luteus LS570. Our report provides very basic information into how actinobacteria interact with plants and direct evidence that the bacterial genus Micrococcus influences the cellular and physiological plant programs ultimately responsible of biomass partitioning.
PMID: 34792622
Pathog Dis , IF:3.166 , 2022 Aug , V80 (1) doi: 10.1093/femspd/ftac029
3-indoleacetonitrile attenuates biofilm formation and enhances sensitivity to imipenem in Acinetobacter baumannii.
Department of Biotechnology, South Campus, Basic Medical Science (Block I), Panjab University, Sector 25, 160014, Chandigarh, India.; Department of Microbiology, South Campus, Basic Medical Science (Block I), Panjab University, Sector 25, 160014, Chandigarh, India.
Acinetobacter baumannii poses a global danger due to its ability to resist most of the currently available antimicrobial agents. Furthermore, the rise of carbapenem-resistant A. baumannii isolates has limited the treatment options available. In the present study, plant auxin 3-indoleacetonitrile (3IAN) was found to inhibit biofilm formation and motility of A. baumannii at sublethal concentration. Mechanistically, 3IAN inhibited the synthesis of the quorum sensing signal 3-OH-C12-HSL by downregulating the expression of the abaI autoinducer synthase gene. 3IAN was found to reduce the minimum inhibitory concentration of A. baumannii ATCC 17978 against imipenem, ofloxacin, ciprofloxacin, tobramycin, and levofloxacin, and significantly decreased persistence against imipenem. Inhibition of efflux pumps by downregulating genes expression may be responsible for enhanced sensitivity and low persistence. 3IAN reduced the resistance to imipenem in carbapenem-resistant A. baumannii isolates by downregulating the expression of OXA beta-lactamases (blaoxa-51 and blaoxa-23), outer membrane protein carO, and transporter protein adeB. These findings demonstrate the therapeutic potential of 3IAN, which could be explored as an adjuvant with antibiotics for controlling A. baumannii infections.
PMID: 35867872
Funct Plant Biol , IF:3.101 , 2022 Sep doi: 10.1071/FP22002
Crucial role of Arabidopsis glutaredoxin S17 in heat stress response revealed by transcriptome analysis.
Heat stress can have detrimental effects on plant growth and development. However, the mechanisms by which the plant is able to perceive changes in ambient temperature, transmit this information, and initiate a temperature-induced response are not fully understood. Previously, we showed that heterologous expression of an Arabidopsis thaliana L. monothiol glutaredoxin AtGRXS17 enhances thermotolerance in various crops, while disruption of AtGRXS17 expression caused hypersensitivity to permissive temperature. In this study, we extend our investigation into the effect of AtGRXS17 and heat stress on plant growth and development. Although atgrxs17 plants were found to exhibit a slight decrease in hypocotyl elongation, shoot meristem development, and root growth compared to wild-type when grown at 22 degrees C, these growth phenotypic differences became more pronounced when growth temperatures were raised to 28 degrees C. Transcriptome analysis revealed significant changes in genome-wide gene expression in atgrxs17 plants compared to wild-type under conditions of heat stress. The expression of genes related to heat stress factors, auxin response, cellular communication, and abiotic stress were altered in atgrxs17 plants in response to heat stress. Overall, our findings indicate that AtGRXS17 plays a critical role in controlling the transcriptional regulation of plant heat stress response pathways.
PMID: 36099929
Micromachines (Basel) , IF:2.891 , 2022 Aug , V13 (9) doi: 10.3390/mi13091423
Microencapsulation of Bacillus velezensis Using Alginate-Gum Polymers Enriched with TiO2 and SiO2 Nanoparticles.
Department of Plant Protection, Faculty of Agriculture, Vali-e-Asr University of Rafsanjan, Rafsanjan 7718897111, Iran.; Department of Chemistry, Faculty of Science, Vali-e-Asr University, Rafsanjan 7718893514, Iran.; Department of Plant Protection, Faculty of Agriculture, Shahid Bahinar University of Kerman, Kerman 7618411764, Iran.; Department of Physics, University of Zabol, Zabol 9861335856, Iran.; Institute of Materials Physics and Engineering, Department of Applied Science and Technology, Politecnico di Torino, 10129 Turin, Italy.
Bacillus bacteria are a group of plant growth stimulants that increase plant growth and resistance to plant pathogens by producing various metabolites. With their large surface area and small size, nanoparticles can be used in controlled-release formulations and increase the efficiency of the desired product. Encapsulation of biological agents in combination with nanoparticles can be an essential step in increasing the performance of these agents in adverse environmental conditions. In this study, which is the result of a collaboration between scientists from Italy and Iran, Bacillus velezensis was encapsulated in alginate combined with whey protein and zedo, mastic, and tragacanth gums in the presence of silica and titania nanoparticles to obtain two-layer and multilayer assemblies acting as novel, smart micro-encapsulation systems. The results of laboratory studies showed that the B. velezensis could produce protease, lipase, siderophore, auxin, and a dissolution of mineral phosphate. Scanning electron microscopy images (SEM) showed that the studied microcapsules were almost spherical. Moisture affinity, swelling, and efficiency of each microcapsule were examined. The results showed that the highest encapsulation efficiency (94.3%) was related to the multilayer formulation of alginate-whey protein-zedo. XRD and FTIR spectroscopy showed that the alginate, whey protein, and zedo were mixed properly and no incompatible composition occurred in the reaction. This study aimed to provide a suitable formulation of biofertilizers based on biodegradable compounds as an alternative to chemical fertilizers, which is low cost and very effective without harming humans and the environment.
PMID: 36144046
J Theor Biol , IF:2.691 , 2022 Nov , V553 : P111261 doi: 10.1016/j.jtbi.2022.111261
Modeling phyllotaxis: From the inhibition potential to the real plant.
Laboratoire de Thermodynamique des Milieux Ioniques et Biologiques, Universite Paris Cite, 45 cours Lassus, 66000 Perpignan, France. Electronic address: jpwalch511@gmail.com.
We developed a new parametrization of the classic Douady and Couder model of phyllotaxis based on the inhibition potential: it allowed us to accurately reproduce the vegetative meristem of Linum usitatissimum displaying Fibonacci phyllotaxis, and the reproductive meristem of Ranunculus repens. We calculated the inhibition potential within the meristem and the auxin concentration at the front. We show that phyllotaxis modes and the convergence of the divergence angles towards "noble" angles are the consequence of minimizing the inhibitory potential under the constraint of decreasing plastochron ratios. Our approach, which gives a physicochemical basis to the van Iterson diagram, produces the same results as approaches based on mechanical constraints, suggesting these are two facets of the same botanical reality.
PMID: 36037857
Dose Response , IF:2.658 , 2022 Jul-Sep , V20 (3) : P15593258221121202 doi: 10.1177/15593258221121202
Wool Wax Extraction From Washing Effluent and Effect on Olea europea Germination and Growth.
Laboratory of Functional Physiology and Valorization of Bio Resources, High Institute of Biotechnology of Beja, University of Jendouba, Beja, Tunisia.; G-TEX B CORPORATION SARL, Bradaa, Tunisia.
Effluents from textile industry using wool pose serious environmental nuisances in Tunisia that are mainly due to their pollutant load and the release of unpleasant odors. In order to minimize these hazards and to take advantage of these wastes for the sake of our environment, the present work consists on valuating wool wax from washing effluent on olive (Olea europea), germination and growth. Extraction was made in water at 70 degrees C or hexane using sonication followed by concentration of the extracts in soxhlet apparatus. Results showed that this waste is characterized by its richness in total lipid content with extraction yields of 60.7 and 95.6%, respectively. GC-MS analysis of wax showed its richness on fatty acids. Six saturated fatty acids ranking from 15 to 27 carbon atoms were characterized. Furthermore, diluted wax at a dose of 1.25 mg/g significantly improves germination of olive seeds by germination index calculation, to reach a maximum of 150 +/- 17%. In fertigation experiment, the use of the same dose of diluted wax promotes plant length to reach 45.7 +/- 2.52 cm. GC-MS analysis after derivatization showed significant enhancement of auxin production in plants treated with 1.25 mg of wax/g of soil compared to control with a concentration of 1.1 +/- .1 and .7 +/- .2 ng/mg, respectively. This leads us to valuate wool wax as environmental friendly natural product in agricultural and fertigation practice of olive plant.
PMID: 36003318
3 Biotech , IF:2.406 , 2022 Oct , V12 (10) : P262 doi: 10.1007/s13205-022-03322-z
Phosphate solubilization and indole acetic acid production by rhizosphere yeast Torulaspora globosa: improvement of culture conditions for better performance in vitro.
Pos-Graduacao Em Producao Vegetal E Bioprocessos Associados, Universidade Federal de Sao Carlos, Rod Anhanguera km 174, Araras, Sao Paulo, Brazil.grid.411247.50000 0001 2163 588X; Departamento de Tecnologia Agroindustrial E Socio-Economia Rural, Universidade Federal de Sao Carlos, Rod. Anhanguera km 174, Araras, Sao Paulo, Brazil.grid.411247.50000 0001 2163 588X; Departamento de Recursos Naturais E Protecao Ambiental, Universidade Federal de Sao Carlos, Rod Anhanguera km 174, Araras, Sao Paulo, Brazil.grid.411247.50000 0001 2163 588X
The rhizosphere yeast Torulaspora globosa is known to produce indole acetic acid (IAA) and to solubilize minerals. Due to the prospective use of this yeast as a biostimulant for agricultural applications, this work aimed to optimize the cultural conditions for both IAA production and phosphate solubilization. For phosphate solubilization, the temperature (20, 25 and 30 degrees C), initial medium pH (3.0, 5.0, and 7.0), and shaker speed (without mixing, 100 rpm, 150 rpm, and 200 rpm) were considered using the one-factor-at-a-time (OFAT) design. Temperature of 25 degrees C, initial medium pH 7.0, and static cultures were the conditions of greatest phosphate solubilization, with 40% of the total phosphorus content solubilized from calcium phosphate (419.86 mg L(-1)) after 48 h. By using the response surface methodology, the maximum IAA production (217.73 microg mL(-1)) was obtained with the highest initial pH 7.0, the lowest nitrogen, and glucose concentrations (5 g L(-1) and 10 g L(-1), respectively) and the lowest agitator speed (100 rpm). Further tests indicated that nitrogen affected significantly IAA production and the absence of nitrogen in the medium promoted higher IAA production (457 microg mL(-1)). The results obtained here may contribute to the scaling up for industrial and agricultural applications of a yeast-based product with T. globosa.
PMID: 36091086
J Nat Med , IF:2.343 , 2022 Sep , V76 (4) : P803-810 doi: 10.1007/s11418-022-01631-4
The ability of callus tissues induced from three Allium plants to accumulate health-beneficial natural products, S-alk(en)ylcysteine sulfoxides.
Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8675, Japan. naokoy@faculty.chiba-u.jp.; Plant Molecular Science Center, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8675, Japan. naokoy@faculty.chiba-u.jp.; School of Pharmacy, Iwate Medical University, 1-1-1 Idaidori, Yahaba, Iwate, 028-3694, Japan.; Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8675, Japan.; Plant Molecular Science Center, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8675, Japan.; RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045, Japan.
S-Alk(en)ylcysteine sulfoxides (CSOs), such as methiin, alliin, and isoalliin, are health-beneficial natural products biosynthesized in the genus Allium. Here, we report the induction of multiple callus tissue lines from three Allium vegetables, onion (A. cepa), Welsh onion (A. fistulosum), and Chinese chive (A. tuberosum), and their ability to accumulate CSOs. Callus tissues were initiated and maintained in the presence of picloram and 2-isopentenyladenine as auxin and cytokinin, respectively. For all plant species tested, the callus tissues almost exclusively accumulated methiin as CSO, while the intact plants contained a substantial amount of isoalliin together with methiin. These results suggest that the cellular developmental conditions and the regulatory mechanisms required for the biosynthesis of methiin are different from those of alliin and isoalliin. The methiin content in the callus tissues of onion and Welsh onion was much higher compared to that in the intact plants, and its cellular concentration could be estimated as 1.9-21.7 mM. The activity of alliinase that degrades CSOs in the callus tissues was much lower than that of the intact plants for onion and Welsh onion, but at similar levels as in the intact plants for Chinese chive. Our findings that the callus tissues of onion and Welsh onion showed high methiin content and low alliinase activity highlighted their potential as a plant-based system for methiin production.
PMID: 35691991
Mol Biol Rep , IF:2.316 , 2022 Sep , V49 (9) : P8815-8825 doi: 10.1007/s11033-022-07731-4
PheGRF4e initiated auxin signaling during moso bamboo shoot development.
Key Laboratory of National Forestry and Grassland Administration/Beijing for Bamboo and Rattan Science and Technology, International Center for Bamboo and Rattan, Beijing, 100102, China.; Key Laboratory of National Forestry and Grassland Administration/Beijing for Bamboo and Rattan Science and Technology, International Center for Bamboo and Rattan, Beijing, 100102, China. gaojian@icbr.ac.cn.
BACKGROUND: As a ubiquitous acid-regulating protein family in eukaryotes, general regulatory factors (GRFs) are active in various life activities of plants. However, detailed investigations of the GRFs gene family in moso bamboo are scarce. METHODS AND RESULTS: Genome-wide characteristics of the GRF gene family in moso bamboo were analyzed using the moso bamboo genome. GRF phylogeny, gene structure, conserved domains, cis-element promoters, and gene expression were systematically analyzed. A total of 20 GRF gene family members were identified in the moso bamboo genome. These genes were divided into epsilon and non-epsilon groups. qRT-PCR (real-time quantitative reverse transcription polymerase chain reaction) showed that PheGRF genes responded to auxin and gibberellin treatment. To further study PheGRF gene functions, a yeast two-hybrid experiment was performed and verified by a bimolecular fluorescence complementation experiment. The results showed that PheGRF4e could interact with PheIAA30 (auxin/indole-3-acetic acid, an Aux/IAA family gene), and both were found to act mainly on the root tip meristem and vascular bundle cells of developing shoots by in situ hybridization assay. CONCLUSIONS: This study revealed that PheGRF genes were involved in hormone response during moso bamboo shoot development, and the possible regulatory functions of PheGRF genes were enriched by the fact that PheGRF4e initiated auxin signaling by binding to PheIAA30.
PMID: 35867290
J Math Biol , IF:2.259 , 2022 Sep , V85 (4) : P41 doi: 10.1007/s00285-022-01793-5
Scaling relations for auxin waves.
Mathematical Institute, Universiteit Leiden, P.O. Box 9512, 2300 RA, Leiden, The Netherlands.; Department of Mathematics, Kennesaw State University, 850 Polytechnic Lane, MD #9085, Marietta, GA, 30060, USA.; Mathematical Institute, Universiteit Leiden, P.O. Box 9512, 2300 RA, Leiden, The Netherlands. hhupkes@math.leidenuniv.nl.; Mathematical Institute and Institute of Biology Leiden, Universiteit Leiden, P.O. Box 9512, 2300 RA, Leiden, The Netherlands.
We analyze an 'up-the-gradient' model for the formation of transport channels of the phytohormone auxin, through auxin-mediated polarization of the PIN1 auxin transporter. We show that this model admits a family of travelling wave solutions that is parameterized by the height of the auxin-pulse. We uncover scaling relations for the speed and width of these waves and verify these rigorous results with numerical computations. In addition, we provide explicit expressions for the leading-order wave profiles, which allows the influence of the biological parameters in the problem to be readily identified. Our proofs are based on a generalization of the scaling principle developed by Friesecke and Pego to construct pulse solutions to the classic Fermi-Pasta-Ulam-Tsingou model, which describes a one-dimensional chain of coupled nonlinear springs.
PMID: 36163567
Curr Microbiol , IF:2.188 , 2022 Sep , V79 (11) : P331 doi: 10.1007/s00284-022-03031-z
Analysis of Blueberry Plant Rhizosphere Bacterial Diversity and Selection of Plant Growth Promoting Rhizobacteria.
School of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong, Shaanxi, China. amy133253@126.com.; School of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong, Shaanxi, China.; Shaanxi Key Laboratory of Bioresources, Shaanxi University of Technology, Hanzhong, Shaanxi, China.; School of Nutrition and Food Sciences, Louisiana State University, Baton Rouge, LA, USA.
Microbial metabolites in rhizosphere soil are important to plant growth. In this study, microbial diversity in blueberry plant rhizosphere soil was characterized using high-throughput amplicon sequencing technology. There were 11 bacterial phyla and three fungal phyla dominating in the soil. In addition, inorganic-phosphate-solubilizing bacteria (iPSB) in the rhizosphere soil were isolated and evaluated by molybdenum-antimony anti-coloration method. Their silicate solubilizing, auxin production, and nitrogen fixation capabilities were also determined. Eighteen iPSB in the rhizosphere soil strains were isolated and identified as Buttiauxella, Paraburkholderia and Pseudomonas. The higher phosphorus-solubilizing capacity and auxin production in blueberry rhizosphere belonged to genus Buttiauxella sp. The strains belong to genus Paraburkholderia had the same function of dissolving both phosphorus and producing auxin, as well as silicate and nitrogen fixation. The blueberry seeds incubated with the strains had higher germination rates. The results of this study could be helpful in developing the plant growth-promoting rhizobacteria (PGPR) method for enhancing soil nutrients to blueberry plant.
PMID: 36156157
Front Biosci (Landmark Ed) , 2022 Aug , V27 (8) : P251 doi: 10.31083/j.fbl2708251
Genome-Wide Identification, Expression and Interaction Analysis of ARF and AUX/IAA Gene Family in Soybean.
Guangdong Provincial Key Laboratory for Plant Epigenetics; Shenzhen Key Laboratory of Marine Bioresource & Eco-environmental Science; Longhua Institute of Innovative Biotechnology; College of Life Sciences and Oceanography, Shenzhen University, 518060 Shenzhen, Guangdong, China.; Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, 518060 Shenzhen, Guangdong, China.; Key Laboratory of Saline-Alkali Vegetative Ecology Restoration, Ministry of Education, College of Life Science, Northeast Forestry University, 150040 Harbin, Heilongjiang, China.; ALBA Synchrotron Light Source, Cerdanyola del Valles, 08290 Barcelona, Spain.; Department of Agronomy, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA.
BACKGROUND: The plant hormones auxin affects most aspects of plant growth and development. The auxin transport and signaling are regulated by different factors that modulate plant morphogenesis and respond to external environments. The modulation of gene expression by Auxin Response Factors (ARFs) and inhibiting Auxin/Indole-3-Acetic Acid (Aux/IAA) proteins are involved in auxin signaling pathways. These components are encoded by gene families with numerous members in most flowering plants. METHODS: However, there is no genome-wide analysis of the expression profile and the structural and functional properties of the ARF and Aux/IAA gene families in soybean. Using various online tools to acquire of genomic and expression data, and analyzing them to differentiate the selected gene family's expression, interaction, and responses in plant growth and development. RESULTS: Here, we discovered 63 GmIAAs and 51 GmARFs in a genome-wide search for soybean and analyzed the genomic, sequential and structural properties of GmARFs and GmIAAs. All of the GmARFs found have the signature B3 DNA-binding (B3) and ARF (Aux rep) domains, with only 23 possessing the C-terminal PB1 (Phox and Bem1) domain (Aux/IAA), according to domain analysis. The number of exons in GmARFs and GmIAAs genes varies from two to sixteen, indicating that the gene structure of GmARFs and GmIAAs is highly variable. Based on phylogenetic analysis, the 51 GmARFs and 63 GmIAAs were classified into I-V and I-VII groups. The expression pattern of GmARFs and GmIAAs revealed that the GmARF expression is more specific to a particular part of the plant; for example, ARF 2, 7, and 11 are highly expressed in the root. In contrast, GmIAAs expression has occurred in various parts of the plants. The interaction of ARF with functional genes showed extensive interactions with genes involved in auxin transport which helps to control plant growth and development. Furthermore, we also elaborate on the DNA-protein interaction of ARFs by identifying the residues involved in DNA recognition. CONCLUSIONS: This study will improve our understanding of the auxin signaling system and its regulatory role in plant growth and development.
PMID: 36042185
Front Biosci (Landmark Ed) , 2022 Aug , V27 (8) : P248 doi: 10.31083/j.fbl2708248
OsDOF11 Promotes Crown Root Formation via Cytokinin in Oryza Sativa.
Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops/Joint International Research Laboratory of Agriculture & Agri-Product Safety, Yangzhou University, 225009 Yangzhou, Jiangsu, China.; Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, 225009 Yangzhou, Jiangsu, China.
BACKGROUND: Crown root is the main part of root system, which performs an important role in rice growth and development, especially in nutrition and water assimilation. Previously, we reported negative feedback regulation loop between Oryza sativa DNA BINDING WITH ONE FINGER 11 (OsDOF11) and cytokinin by Oryza sativa CYTOKININ OXIDASE/DEHYDROGENASE 4 (OsCKX4) in rice development. METHODS: Reverse transcription quantitative RT-PCR analyses was used to analyze the related gene transcript level. Nitrogen and hormone were measured by CHN-Nitrogen analyser and Liquid chromatography mass spectrometer, respectively. Exogenous application of cytokinin and [13C] sucrose labeled stable isotope uptake experiments help us to explain the relationship between OsDOF11 and cytokinin. RESULTS: We demonstrate the role of OsDOF11 in root development. We note that the loss function of OsDOF11 displays the reduced crown roots number, low activity of nitrogen assimilation and low content of cytokinin and auxin. The expression level of WUSCHEL-related homeobox (OsWOX11), A-type response regulator 2 (OsRR2), OsRR3, and OsCKX4 were decreased in osdof11-1, as well as in OsDOF11 RNA interference 9 mutants (RNAi-9 lines). Through Exogenous application of multiple concentrations of cytokinin as treatment to osdof11-1 mutant, RNAi-9 lines, and wild type (WT). We found that the crown roots number of osdof11-1 plants were rescued as the cytokinin concentration increased gradually from 1 muM to 10 muM, but the effect was weaker in RNAi-9 line. And cytokinin inhibited sucrose uptake activity from Murashige-Skoog medium with 3.0% sucrose (MS30) by OsDOF11 in rice root. CONCLUSIONS: OsDOF11 promotes crown root formation via cytokinin in oryza sativa. These results provide a physiological basis for further analysis of the OsDOF11 function of in rice root development.
PMID: 36042159
Microbiol Resour Announc , 2022 Sep , V11 (9) : Pe0042522 doi: 10.1128/mra.00425-22
Draft Genome Sequence of Bacillus paralicheniformis Strain GSFE7, a Halotolerant Plant Growth-Promoting Bacterial Endophyte Isolated from Cultivated Saline Areas of the Dead Sea Region.
Department of Land, Water, and Environment, School of Agriculture, The University of Jordan, Amman, Jordan.; Department of Biological Sciences, School of Science, The University of Jordan, Amman, Jordan.; Hamdi Mango Center for Scientific Research, The University of Jordan, Amman, Jordan.
Here, we report the draft genome sequence of Bacillus paralicheniformis strain GSFE7, which was isolated from saline fields near the Dead Sea region. The genome was 4,452,800 bp in size and contained 4,382 coding sequences. Several genes were predicted to be involved in auxin production, nitrogen fixation, phosphate mobilization, and putative production of siderophores and antibiotics such as bacitracin, butirosin, and fengycin.
PMID: 35950866
Plant Commun , 2022 Sep , V3 (5) : P100351 doi: 10.1016/j.xplc.2022.100351
Natural variation in the transcription factor REPLUMLESS contributes to both disease resistance and plant growth in Arabidopsis.
School of Life Sciences and School of Advanced Agricultural Sciences, State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China.; School of Life Sciences and School of Advanced Agricultural Sciences, State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China; Beijing Key Laboratory of Environment Friendly Management on Fruit Diseases and Pests in North China, Institute of Plant Protection, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China.; School of Life Sciences and School of Advanced Agricultural Sciences, State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China. Electronic address: deng@pku.edu.cn.; School of Life Sciences and School of Advanced Agricultural Sciences, State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China. Electronic address: heguangming@pku.edu.cn.
When attacked by pathogens, plants need to reallocate energy from growth to defense to fend off the invaders, frequently incurring growth penalties. This phenomenon is known as the growth-defense tradeoff and is orchestrated by a hardwired transcriptional network. Altering key factors involved in this network has the potential to increase disease resistance without growth or yield loss, but the mechanisms underlying such changes require further investigation. By conducting a genome-wide association study (GWAS) of leaves infected by the hemi-biotrophic bacterial pathogen Pseudomonas syringae pv. tomato (Pst) DC3000, we discovered that the Arabidopsis transcription factor REPLUMLESS (RPL) is necessary for bacterial resistance. More importantly, RPL functions in promoting both disease resistance and growth. Transcriptome analysis revealed a cluster of genes in the GRETCHEN HAGEN 3 (GH3) family that were significantly upregulated in rpl mutants, leading to the accumulation of indole-3-acetic acid-aspartic acid (IAA-Asp). Consistent with this observation, transcripts of virulence effector genes were activated by IAA-Asp accumulated in the rpl mutants. We found that RPL protein could directly bind to GH3 promoters and repress their expression. RPL also repressed flavonol synthesis by directly repressing CHI expression and thus activated the auxin transport pathway, which promotes plant growth. Therefore, RPL plays an important role in plant immunity and functions in the auxin pathway to optimize Arabidopsis growth and defense.
PMID: 35752937
Plant Commun , 2022 Sep , V3 (5) : P100327 doi: 10.1016/j.xplc.2022.100327
Right time, right place: The dynamic role of hormones in rhizobial infection and nodulation of legumes.
Discipline of Biological Sciences, School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, TAS 7001, Australia.; Discipline of Biological Sciences, School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, TAS 7001, Australia. Electronic address: eloise.foo@utas.edu.au.
Many legume plants form beneficial associations with rhizobial bacteria that are hosted in new plant root organs, nodules, in which atmospheric nitrogen is fixed. This association requires the precise coordination of two separate programs, infection in the epidermis and nodule organogenesis in the cortex. There is extensive literature indicating key roles for plant hormones during nodulation, but a detailed analysis of the spatial and temporal roles of plant hormones during the different stages of nodulation is required. This review analyses the current literature on hormone regulation of infection and organogenesis to reveal the differential roles and interactions of auxin, cytokinin, brassinosteroids, ethylene, and gibberellins during epidermal infection and cortical nodule initiation, development, and function. With the exception of auxin, all of these hormones suppress infection events. By contrast, there is evidence that all of these hormones promote nodule organogenesis, except ethylene, which suppresses nodule initiation. This differential role for many of the hormones between the epidermal and cortical programs is striking. Future work is required to fully examine hormone interactions and create a robust model that integrates this knowledge into our understanding of nodulation pathways.
PMID: 35605199