Dev Cell , IF:10.092 , 2020 Nov , V55 (3) : P367-380.e6 doi: 10.1016/j.devcel.2020.08.005
The GSK3-like Kinase BIN2 Is a Molecular Switch between the Salt Stress Response and Growth Recovery in Arabidopsis thaliana.
State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China.; Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610064, China.; State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China. Electronic address: guoyan@cau.edu.cn.
Plant stress responses involve dynamic growth regulation. Growth is restricted in harsh environmental conditions and is rapidly restored when conditions improve. Here, we identified BIN2, a glycogen synthase kinase 3 (GSK3)-like kinase, as a molecular switch in the transition to robust growth after salt stress in Arabidopsis thaliana. In the rapid recovery phase after salt stress, the calcium sensors SOS3 and SCaBP8 perceive a calcium signal and promote BIN2 localization to the plasma membrane to repress the salt stress response, and BIN2 inhibits SOS2 activity and enhances growth by releasing BZR1/BES1 transcriptional activity. The expression of stress- and brassinosteroid-responsive genes is coordinately regulated during this process. bin2-3bil1 and bin2-3bil2 mutants defective in BIN2 and its homologs BIL1 and BIL2, respectively, are hyposensitive to salt stress. Our study suggests that salt signaling modulates the subcellular localization and interactions of BIN2. By phosphorylating different substrates, BIN2 regulates the salt stress response and growth recovery.
PMID: 32891194
Plant Cell , IF:9.618 , 2020 Nov , V32 (11) : P3598-3612 doi: 10.1105/tpc.20.00384
Endocytosis of BRASSINOSTEROID INSENSITIVE1 Is Partly Driven by a Canonical Tyr-Based Motif.
Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium.; Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium.; Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria.; Department of Plant Biology, University of Illinois Urbana-Champaign, Urbana, Illinois 61801.; Plant Science Research Laboratory (LRSV), UMR5546 CNRS/Universite Toulouse 3, 24 chemin de Borde Rouge, 31320 Auzeville-Tolosane, France.; Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium eurus@psb.vib-ugent.be.
Clathrin-mediated endocytosis (CME) and its core endocytic machinery are evolutionarily conserved across all eukaryotes. In mammals, the heterotetrameric adaptor protein complex-2 (AP-2) sorts plasma membrane (PM) cargoes into vesicles via the recognition of motifs based on Tyr or di-Leu in their cytoplasmic tails. However, in plants, very little is known about how PM proteins are sorted for CME and whether similar motifs are required. In Arabidopsis (Arabidopsis thaliana), the brassinosteroid (BR) receptor BR INSENSITIVE1 (BRI1) undergoes endocytosis, which depends on clathrin and AP-2. Here, we demonstrate that BRI1 binds directly to the medium AP-2 subunit (AP2M). The cytoplasmic domain of BRI1 contains five putative canonical surface-exposed Tyr-based endocytic motifs. The Tyr-to-Phe substitution in Y898KAI reduced BRI1 internalization without affecting its kinase activity. Consistently, plants carrying the BRI1(Y898F) mutation were hypersensitive to BRs. Our study demonstrates that AP-2-dependent internalization of PM proteins via the recognition of functional Tyr motifs also operates in plants.
PMID: 32958564
Plant J , IF:6.141 , 2020 Nov doi: 10.1111/tpj.15086
The AGCVIII kinase Dw2 modulates cell proliferation, endomembrane trafficking, and MLG/xylan cell wall localization in elongating stem internodes of Sorghum bicolor.
Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas, 77843, USA.; Department of Plant Biology, Michigan State University, East Lansing, Michigan, 48824, USA.; Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, Michigan, 48824, USA.; MSU-DOE Plant Research Lab, Michigan State University, East Lansing, Michigan, 48824, USA.; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, 48824, USA.
Stems of bioenergy sorghum, a drought tolerant C4 grass, contain up to 50 nodes and internodes of varying length that span 4-5 meters and account for ~84% of harvested biomass. Stem internode growth impacts plant height and biomass accumulation and is regulated by brassinosteroid signaling, auxin transport, and gibberellin biosynthesis. In addition, an AGCVIII kinase (Dw2) regulates sorghum stem internode growth, but the underlying mechanism and signaling network are unknown. Here we provide evidence that mutation of Dw2 reduces cell proliferation in internode intercalary meristems, inhibits endocytosis, and alters the distribution of heteroxylan and mixed linkage glucan in cell walls. Phosphoproteomic analysis showed that Dw2 signaling influences the phosphorylation of proteins involved in lipid signaling (PLDdelta), endomembrane trafficking, hormone, light and receptor signaling, and photosynthesis. Together, our results show that Dw2 modulates endomembrane function and cell division during sorghum internode growth providing insight into the regulation of monocot stem development.
PMID: 33211340
J Exp Bot , IF:5.908 , 2020 Nov doi: 10.1093/jxb/eraa544
Maize transcription factor ZmBES1/BZR1-5 positively regulates kernel size.
Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region, Ministry of Agriculture; Maize Research Institute, Sichuan Agricultural University, Chengdu, China.; Department of Plant Biology, University of California, Davis, CA, USA.
The BES1/BZR1 transcription factors regulate the expression of brassinosteroid responsive genes and play pivotal roles in plant development. However, the function of BES1/BZR1 regulating kernel development remains unclear. In this study, maize ZmBES1/BZR1-5 is found to positively regulate kernel size. Candidate-gene association analysis showed that four and three SNPs related to ZmBES1/BZR1-5 were significantly associated with kernel width and 100-kernel weight in 513 diverse maize inbred lines, respectively. Overexpression of ZmBES1/BZR1-5 gene in Arabidopsis and rice both significantly increased seed size and weight, as well as smaller kernel produced in maize Mu transposon insertion and EMS mutants. The ZmBES1/BZR1-5 protein contains bHLH and BAM domains, shows no transcriptional activity as monomer but forms homodimer through BAM domain, and locates in nucleus. Chromatin immunoprecipitation sequencing (ChIP-seq), yeast one-hybrid (Y1H) and dual-luciferase assay demonstrate that ZmBES1/BZR1-5 protein binds to the promoter of AP2/EREBP genes (Zm00001d010676 and Zm00001d032077) and inhibits their transcription. cDNA library screening shows that ZmBES1/BZR1-5 interacts with casein kinase II subunit beta4 (ZmCKIIbeta4) and ferredoxin 2 (ZmFdx2) in vitro and vivo, respectively. Taken together, the study suggests that ZmBES1/BZR1-5 positively regulates kernel size and provides new insights into understanding the mechanism of kernel development in maize.
PMID: 33206180
J Exp Bot , IF:5.908 , 2020 Nov doi: 10.1093/jxb/eraa524
An S-ribonuclease binding protein EBS1 and brassinolide signaling are specifically required for Arabidopsis tolerance to bicarbonate.
State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin'an, Hangzhou, China.; Key Laboratory of Saline-Alkali Vegetation Ecology Restoration, Ministry of Education, College of Life Science, Northeast Forestry University, Harbin , China.; School of Biological Sciences, Nanyang Technological University, Nanyang Drive, Singapore,Singapore.; State Key Laboratory of Cotton Biology, Department of Biology, Institute of Plant Stress Biology, Henan University, Kaifeng, China.
Bicarbonate (NaHCO3) stress was usually considered to be a mixed stress with salts and high pH. The NaHCO3-specific signaling in plants were rarely reported. In this study, transcriptome analyses was conducted in order to identify the NaHCO3-specific singling in Arabidopsis. Weighted correlation network analysis were performed to isolate the NaHCO3-specific modules in comparison to acetate treatment. The genes in the NaHCO3-root-specific module, which exhibited opposite expressions between NaHCO3 and sodium acetate treatments, were further examined with their corresponding knock-out mutants. The gene Exclusively Bicarbonate Sensitive 1 (EBS1) encoding an S-ribonuclease binding protein was identified to be specifically involved in plant tolerance to NaHCO3, but not to the other two alkaline salts, acetate and phosphate. We also identified the genes that commonly regulated by bicarbonate, acetate and phosphate. Multiple brassinosteroid associated gene ontology terms were enriched in these genes. Via genetic assays, it was found that brassinosteroid signaling positively regulated plant tolerance to NaHCO3 stress while negatively regulated tolerance to acetate and phosphate. Overall, our data genetically identified the bicarbonate-specific genes, and conclude that alkaline stress is mainly dependent on the specificities of the weak acid ions rather than high pH.
PMID: 33165537
Development , IF:5.611 , 2020 Nov doi: 10.1242/dev.196618
Asynchrony of ovule primordia initiation in Arabidopsis.
Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Joint Center for Sing Cell Biology, Shanghai Jiao Tong University, Shanghai 200240, China.; Faculty of Mechanical Engineering and Mechanics, Ningbo University, Ningbo, Zhejiang, 315211, China.; State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, and National Center for Plant Gene Research, Beijing 100101, China.; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, 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, Shanghai 200032, China.; Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Joint Center for Sing Cell Biology, Shanghai Jiao Tong University, Shanghai 200240, China whlin@sjtu.edu.cn.
Plant ovule initiation determines the maximum of ovule number and has a great impact on the seed number per fruit. The detailed processes of ovule initiation have not been accurately described although two connected processes, gynoecium and ovule development, have been investigated. Here we report that ovules initiate asynchronously. The first group of ovule primordia grows out, the placenta elongate, the boundaries of existing ovules enlarge and new group of primordia initiates from the boundaries. The expression pattern of different marker genes during ovule development illustrates that this asynchronicity continues throughout whole ovule development. PIN-FORMED1 polar distribution and auxin response maxima correlate to ovule primordia initiation asynchronous. We established computational modeling to show how auxin dynamics influence ovule primordia initiation. Brassinosteroid signaling positively regulates ovule number by promoting placentae size and ovule primordia initiation through strengthening auxin response. Transcriptomic analysis demonstrates numerous known regulators of ovule development and hormones signaling, and many new genes are identified to involve in ovule development. Taken together, our results illustrate the ovule primordia initiate asynchronously and the hormone signal involve in the asynchrony.
PMID: 33234714
J Integr Plant Biol , IF:4.885 , 2020 Nov doi: 10.1111/jipb.13033
The novel peptide NbPPI1 identified from Nicotiana benthamiana triggers immune responses and enhances resistance against Phytophthora pathogens.
State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A&F University, Yangling, 712100, China.; State Key Laboratory of Crop Stress Biology for Arid Areas and College of Agronomy, Northwest A&F University, Yangling, 712100, China.; State Key Laboratory of Crop Stress Biology for Arid Areas and College of life sciences, Northwest A&F University, Yangling, 712100, China.
In plants, recognition of small secreted peptides, such as damage/danger-associated molecular patterns (DAMPs), regulates diverse processes, including stress and immune responses. Here, we identified an SGPS (Ser-Gly-Pro-Ser) motif-containing peptide, Nicotiana tabacum NtPROPPI, and its two homologs in Nicotiana benthamiana, NbPROPPI1 and NbPROPPI2. Phytophthora parasitica infection and salicylic acid (SA) treatment induced NbPROPPI1/2 expression. Moreover, SignalP predicted that the 89-amino acid NtPROPPI includes a 24-amino acid N-terminal signal peptide and NbPROPPI1/2-GFP fusion proteins were mainly localized to the periplasm. Transient expression of NbPROPPI1/2 inhibited P. parasitica colonization, and NbPROPPI1/2 knockdown rendered plants more susceptible to P. parasitica. An eight-amino-acid segment in the NbPROPPI1 C-terminus was essential for its immune function and a synthetic 20-residue peptide, NbPPI1, derived from the C-terminus of NbPROPPI1 provoked significant immune responses in N. benthamiana. These responses led to enhanced accumulation of reactive oxygen species, activation of mitogen-activated protein kinases, and up-regulation of the defense genes Flg22-induced receptor-like kinase (FRK) and WRKY DNA-binding protein 33 (WRKY33). The NbPPI1-induced defense responses require Brassinosteroid insensitive 1-associated receptor kinase 1 (BAK1). These results suggest that NbPPI1 functions as a DAMP in N. benthamiana; this novel DAMP provides a potentially useful target for improving resistance to P. parasitica. This article is protected by copyright. All rights reserved.
PMID: 33205861
J Integr Plant Biol , IF:4.885 , 2020 Nov , V62 (11) : P1674-1687 doi: 10.1111/jipb.12975
The epidermis-specific cyclin CYCP3;1 is involved in the excess brassinosteroid signaling-inhibited root meristem cell division.
State Key Laboratory of Genetic Engineering, Department of Genetics, School of Life Sciences, Fudan University, Shanghai, 200433, China.; State Key Laboratory of Crop Stress Adaptation and Improvement, Henan University, Kaifeng, 475001, China.
Cell division is precisely regulated and highly tissue-specific; studies have suggested that diverse signals in the epidermis, especially the epidermal brassinosteroids (BRs), can regulate root growth. However, the underlying molecular mechanisms that integrate hormonal cues such as BR signaling with other endogenous, tissue-specific developmental programs to regulate epidermal cell proliferation remain unclear. In this study, we used molecular and biochemical approaches, microscopic imaging and genetic analysis to investigate the function and mechanisms of a P-type cyclin in root growth regulation. We found that CYCP3;1, specifically expressed in the root meristem epidermis and lateral root cap, can regulate meristem cell division. Mitotic analyses and biochemical studies demonstrated that CYCP3;1 promotes cell division at the G2-M duration by associating and activating cyclin-dependent kinase B2-1 (CDKB2;1). Furthermore, we found that CYCP3;1 expression was inhibited by BR signaling through BRI1-EMS-SUPPRESSOR1 (BES1), a positive downstream transcription factor in the BR signaling pathway. These findings not only provide a mechanism of how root epidermal-specific regulators modulate root growth, but also reveal why the excess of BRs or enhanced BR signaling inhibits cell division in the meristem to negatively regulate root growth.
PMID: 32470187
J Cell Sci , IF:4.573 , 2020 Nov , V133 (22) doi: 10.1242/jcs.246728
It takes two to tango - molecular links between plant immunity and brassinosteroid signalling.
Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA fandortiz@tamu.edu eurus@psb.vib-ugent.be.; Amazonian Research Center Cimaz-Macagual, University of the Amazon, Florencia 180002622, Colombia.; Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA.; Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium fandortiz@tamu.edu eurus@psb.vib-ugent.be.; Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium.
In response to the invasion of microorganisms, plants actively balance their resources for growth and defence, thus ensuring their survival. The regulatory mechanisms underlying plant immunity and growth operate through complex networks, in which the brassinosteroid phytohormone is one of the central players. In the past decades, a growing number of studies have revealed a multi-layered crosstalk between brassinosteroid-mediated growth and plant immunity. In this Review, by means of the tango metaphor, we immerse ourselves into the intimate relationship between brassinosteroid and plant immune signalling pathways that is tailored by the lifestyle of the pathogen and modulated by other phytohormones. The plasma membrane is the unique stage where brassinosteroid and immune signals are dynamically integrated and where compartmentalization into nanodomains that host distinct protein consortia is crucial for the dance. Shared downstream signalling components and transcription factors relay the tango play to the nucleus to activate the plant defence response and other phytohormonal signalling pathways for the finale. Understanding how brassinosteroid and immune signalling pathways are integrated in plants will help develop strategies to minimize the growth-defence trade-off, a key challenge for crop improvement.
PMID: 33239345
Theor Appl Genet , IF:4.439 , 2020 Nov doi: 10.1007/s00122-020-03719-5
Multiple origins of Indian dwarf wheat by mutations targeting the TREE domain of a GSK3-like kinase for drought tolerance, phosphate uptake, and grain quality.
252 McFadden Biostress Laboratory, Department of Biology and Microbiology, South Dakota State University, Brookings, SD, 57007, USA.; Plant Pathology Department, Kansas State University, Manhattan, KS, 66502, USA.; Institute of Experimental Botany of the Czech Academy of Sciences, 77900, Olomouc, Czech Republic.; 252 McFadden Biostress Laboratory, Department of Biology and Microbiology, South Dakota State University, Brookings, SD, 57007, USA. Wanlong.li@sdstate.edu.
KEY MESSAGE: Multiple origins of Indian dwarf wheat were due to two mutations targeting the same TREE domain of a GSK3-like kinase, and these mutations confer to enhanced drought tolerance and increased phosphate and nitrogen accumulation for adaptation to the dry climate of Indian and Pakistan. Indian dwarf wheat, featured by the short stature, erect leaves, dense spikes, and small, spherical grains, was a staple crop in India and Pakistan from the Bronze Age until the early 1900s. These morphological features are controlled by a single locus Sphaerococcum 1 (S1), but the genetic identity of the locus and molecular mechanisms underlying the selection of this wheat type are unknown. In this study, we showed that the origin of Indian dwarf wheat was due to two independent missense mutations targeting the conserved TREE domain of a GSK3-like kinase, which is homologous to the Arabidopsis BIN2 protein, a negative regulator in brassinosteroid signaling. The S1 protein is involved in brassinosteroid signaling by physical interaction with the wheat BES1/BZR1 proteins. The dwarf alleles are insensitive to brassinosteroid, upregulates brassinosteroid biosynthetic genes, significantly enhanced drought tolerance, facilitated phosphate accumulation, and increased high molecular weight glutenins. It is the enhanced drought tolerance and accumulation of nitrogen and phosphate that contributed to the adaptation of such a small-grain form of wheat to the dry climate of India and Pakistan. Thus, our research not only identified the genetic events underlying the origin of the Indian dwarf wheat, but also revealed the function of brassinosteroid in the regulation of drought tolerance, phosphate homeostasis, and grain quality.
PMID: 33164159
Front Plant Sci , IF:4.402 , 2020 , V11 : P583666 doi: 10.3389/fpls.2020.583666
Modes of Brassinosteroid Activity in Cold Stress Tolerance.
Biotechnology of Horticultural Crops, School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany.
Cold stress is a significant environmental factor that negatively affects plant growth and development in particular when it occurs during the growth phase. Plants have evolved means to protect themselves from damage caused by chilling or freezing temperatures and some plant species, in particular those from temperate geographical zones, can increase their basal level of freezing tolerance in a process termed cold acclimation. Cold acclimation improves plant survival, but also represses growth, since it inhibits activity of the growth-promoting hormones gibberellins (GAs). In addition to GAs, the steroid hormones brassinosteroids (BRs) also take part in growth promotion and cold stress signaling; however, in contrast to Gas, BRs can improve cold stress tolerance with fewer trade-offs in terms of growth and yields. Here we summarize our current understanding of the roles of BRs in cold stress responses with a focus on freezing tolerance and cold acclimation pathways.
PMID: 33240301
Sci Rep , IF:3.998 , 2020 Nov , V10 (1) : P18913 doi: 10.1038/s41598-020-75421-x
Analysis of a radiation-induced dwarf mutant of a warm-season turf grass reveals potential mechanisms involved in the dwarfing mutant.
Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China.; Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China. mlchai@zju.edu.cn.; Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China. qiaomeiw@zju.edu.cn.; Plant Biotechnology Resource and Outreach Center, Department of Horticulture, Michigan State University, East Lansing, MI, 48824, USA. songg@msu.edu.
Zoysia matrella [L.] Merr. is a widely cultivated warm-season turf grass in subtropical and tropical areas. Dwarf varieties of Z. matrella are attractive to growers because they often reduce lawn mowing frequencies. In this study, we describe a dwarf mutant of Z. matrella induced from the (60)Co-gamma-irradiated calluses. We conducted morphological test and physiological, biochemical and transcriptional analyses to reveal the dwarfing mechanism in the mutant. Phenotypically, the dwarf mutant showed shorter stems, wider leaves, lower canopy height, and a darker green color than the wild type (WT) control under the greenhouse conditions. Physiologically, we found that the phenotypic changes of the dwarf mutant were associated with the physiological responses in catalase, guaiacol peroxidase, superoxide dismutase, soluble protein, lignin, chlorophyll, and electric conductivity. Of the four endogenous hormones measured in leaves, both indole-3-acetic acid and abscisic acid contents were decreased in the mutant, whereas the contents of gibberellin and brassinosteroid showed no difference between the mutant and the WT control. A transcriptomic comparison between the dwarf mutant and the WT leaves revealed 360 differentially-expressed genes (DEGs), including 62 up-regulated and 298 down-regulated unigenes. The major DEGs related to auxin transportation (e.g., PIN-FORMED1) and cell wall development (i.e., CELLULOSE SYNTHASE1) and expansin homologous genes were all down-regulated, indicating their potential contribution to the phenotypic changes observed in the dwarf mutant. Overall, the results provide information to facilitate a better understanding of the dwarfing mechanism in grasses at physiological and transcript levels. In addition, the results suggest that manipulation of auxin biosynthetic pathway genes can be an effective approach for dwarfing breeding of turf grasses.
PMID: 33144613
Tree Physiol , IF:3.655 , 2020 Nov doi: 10.1093/treephys/tpaa164
HrCYP90B1 modulating brassinosteroid biosynthesis in sea buckthorn (Hippophae rhamnoides L) against fruit fly (Rhagoletis batava obseuriosa Kol.) infection.
College of Life Science, Institute of Life Science and Green Development, Hebei University, Baoding, China.; Hebei Research Center for Geoanalysis, Baoding, China.; Desert Forest Experimental Center, Chinese Academy of Forestry, Dengkou, China.
Sea buckthorn is an important ecological and economic tree species, and its berries have been severely damaged by sea buckthorn fruit fly, Rhagoletis batava obseuriosa Kol. (Diptera: Tephritidae) (RBO). Brassinosteroid (BR) is widely involved in stress tolerance of plant. However, limited knowledge exists regarding the molecular mechanisms underlying insect resistance. Here, we found that BR content was much higher in sea buckthorn fruits with RBO infection than non-infection, and the damage rates of fruit with BR treatment were significantly lower than that of non-treatment. It indicated that BR could enhance RBO resistance in sea buckthorn. Several BR biosynthesis related genes HrCYPs (CYP85A1/85A2/90A1/90B1/90C1/90D1/92A6/724B/734A1) were obtained and identified based on transcriptome analysis, of which the most up-regulated gene in fruits was HrCYP90B1 under RBO and mechanical damage. Overexpression of HrCYP90B1 in Arabidopsis thaliana showed BR and salicylic acid (SA) content was significantly increased, the substrate campesterol (CR) of HrCYP90B1 content decreased. Further studies revealed that silencing HrCYP90B1 by virus-induced gene silencing (VIGS) resulted in decrease of BR, SA and defense-related enzymes contents, increase of CR content. Silencing HrCYP90B1 also caused suppression of SA and activation of jasmonic acid (JA) pathways, enabling enhanced of RBO susceptibility and more damage of fruits. Taken together, we obtained evidence that HrCYP90B1 was a positive regulator in RBO-resistance improvement in sea buckthorn, which will provide comprehensive insights into the tree defense system of sea buckthorn to pest infection.
PMID: 33238299
Plants (Basel) , IF:2.762 , 2020 Nov , V9 (11) doi: 10.3390/plants9111607
Gene Mapping, Genome-Wide Transcriptome Analysis, and WGCNA Reveals the Molecular Mechanism for Triggering Programmed Cell Death in Rice Mutant pir1.
State Key Laboratory of Subtropical Silviculture, Zhejiang A & F University, Hangzhou 311300, China.; State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-Products, Key Laboratory of Biotechnology for Plant Protection, Ministry of Agriculture, and Rural Affairs, Zhejiang Provincial Key Laboratory of Biotechnology for Plant Protection, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Science, Hangzhou 310021, China.; Plant Pathogens Laboratory, College of Plant Protection, Shenyang Agricultural University, Shenyang 210095, China.; College of Plant Protection, Yunnan Agricultural University, Kunming 650000, China.; College of Plant Protection, Fujian A & F University, Fuzhou 350002, China.; State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-Products, Key Laboratory of Biotechnology for Plant Protection, Ministry of Agriculture, and Rural Affairs, Zhejiang Provincial Key Laboratory of Biotechnology for Plant Protection, Institute of Plant Virology, Ningbo University, Ningbo 315211, China.
Programmed cell death (PCD) is involved in plant growth and development and in resistance to biotic and abiotic stress. To understand the molecular mechanism that triggers PCD, phenotypic and physiological analysis was conducted using the first three leaves of mutant rice PCD-induced-resistance 1(pir1) and its wild-type ZJ22. The 2nd and 3rd leaves of pir1 had a lesion mimic phenotype, which was shown to be an expression of PCD induced by H2O2-accumulation. The PIR1 gene was mapped in a 498 kb-interval between the molecular markers RM3321 and RM3616 on chromosome 5, and further analysis suggested that the PCD phenotype of pir1 is controlled by a novel gene for rice PCD. By comparing the mutant with wild type rice, 1679, 6019, and 4500 differentially expressed genes (DEGs) were identified in the three leaf positions, respectively. KEGG analysis revealed that DEGs were most highly enriched in phenylpropanoid biosynthesis, alpha-linolenic acid metabolism, and brassinosteroid biosynthesis. In addition, conjoint analysis of transcriptome data by weighted gene co-expression network analysis (WGCNA) showed that the turquoise module of the 18 identified modules may be related to PCD. There are close interactions or indirect cross-regulations between the differential genes that are significantly enriched in the phenylpropanoid biosynthesis pathway and the hormone biosynthesis pathway in this module, which indicates that these genes may respond to and trigger PCD.
PMID: 33228024
Plants (Basel) , IF:2.762 , 2020 Nov , V9 (11) doi: 10.3390/plants9111566
The Turnera Style S-Locus Gene TsBAHD Possesses Brassinosteroid-Inactivating Activity When Expressed in Arabidopsis thaliana.
School of Biological Sciences, Washington State University, PO Box 644236, Pullman, WA 99164-4236, USA.; Department of Biology, York University, 4700 Keele Street, Toronto, ON M3J1P3, Canada.; Department of Crops and Soils, Washington State University, PO Box 644236, Pullman, WA 99164, USA.
Heterostyly distinct hermaphroditic floral morphs enforce outbreeding. Morphs differ structurally, promote cross-pollination, and physiologically block self-fertilization. In Turnera the self-incompatibility (S)-locus controlling heterostyly possesses three genes specific to short-styled morph genomes. Only one gene, TsBAHD, is expressed in pistils and this has been hypothesized to possess brassinosteroid (BR)-inactivating activity. We tested this hypothesis using heterologous expression in Arabidopsis thaliana as a bioassay, thereby assessing growth phenotype, and the impacts on the expression of endogenous genes involved in BR homeostasis and seedling photomorphogenesis. Transgenic A. thaliana expressing TsBAHD displayed phenotypes typical of BR-deficient mutants, with phenotype severity dependent on TsBAHD expression level. BAS1, which encodes an enzyme involved in BR inactivation, was downregulated in TsBAHD-expressing lines. CPD and DWF, which encode enzymes involved in BR biosynthesis, were upregulated. Hypocotyl growth of TsBAHD dwarfs responded to application of brassinolide in light and dark in a manner typical of plants over-expressing genes encoding BR-inactivating activity. These results provide empirical support for the hypothesis that TsBAHD possesses BR-inactivating activity. Further this suggests that style length in Turnera is controlled by the same mechanism (BR inactivation) as that reported for Primula, but using a different class of enzyme. This reveals interesting convergent evolution in a biochemical mechanism to regulate floral form in heterostyly.
PMID: 33202834
3 Biotech , IF:1.798 , 2020 Nov , V10 (11) : P466 doi: 10.1007/s13205-020-02454-4
Plant growth regulators: a sustainable approach to combat pesticide toxicity.
School of Bioengineering and Biosciences, Lovely Professional University, Phagwara, Punjab 144411 India.grid.449005.c; Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, Punjab 143005 India.grid.411894.10000 0001 0726 8286; Department of Botany, S.P College, Cluster University, Srinagar, Kashmir 190005 India.grid.507608.c
Pesticides are chemical substances intended for preventing or controlling pests. These are toxic substances which contaminate soil, water bodies and vegetative crops. Excessive use of pesticides may cause destruction of biodiversity. In plants, pesticides lead to oxidative stress, inhibition of physiological and biochemical pathways, induce toxicity, impede photosynthesis and negatively affect yield of crops. Increased production of reactive oxygen species like superoxide radicals, O(-) 2 hydrogen peroxide, H2O2; singlet oxygen, O2; hydroxyl radical, OH(-); and hydroperoxyl radical HO2-, causes damage to protein, lipid, carbohydrate and DNA within plants. Plant growth regulators (PGR) are recognized for promoting growth and development under optimal as well as stress conditions. PGR combat adverse effect by acting as chemical messenger and under complex regulation, enable plants to survive under stress conditions. PGR mediate various physiological and biochemical responses, thereby reducing pesticide-induced toxicity. Exogenous applications of PGRs, such as brassinosteroid, cytokinins, salicylic acid, jasmonic acid, etc., mitigate pesticide toxicity by stimulating antioxidant defense system and render tolerance towards stress conditions. They provide resistance against pesticides by controlling production of reactive oxygen species, nutrient homeostasis, increase secondary metabolite production, and trigger antioxidant mechanisms. These phytohormones protect plants against oxidative damage by activating mitogen-stimulated protein kinase cascade. Current study is based on reported research work that has shown the effect of PGR in promoting plant growth subjected to pesticide stress. The present review covers the aspects of pesticidal response of plants and evaluates the contribution of PGRs in mitigating pesticide-induced stress and increasing the tolerance of plants. Further, the study suggests the use of PGRs as a tool in mitigating effects of pesticidal stress together with improved growth and development.
PMID: 33088662