Plant Cell , IF:11.277 , 2021 Nov doi: 10.1093/plcell/koab267
Prediction of conserved and variable heat and cold stress response in maize using cis-regulatory information.
Department of Plant and Microbial Biology, University of Minnesota, Saint Paul, MN 55108.; School of Agriculture and Food Sciences, The University of Queensland, Brisbane, QLD 4072, Australia.; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824.
Changes in gene expression are important for responses to abiotic stress. Transcriptome profiling of heat- or cold-stressed maize genotypes identifies many changes in transcript abundance. We used comparisons of expression responses in multiple genotypes to identify alleles with variable response to heat or cold stress and to distinguish examples of cis- or trans-regulatory variation for stress-responsive expression changes. We used motifs enriched near the transcription start sites for thermal stress-responsive genes to develop predictive models of gene expression responses. Prediction accuracies can be improved focusing only on motifs within unmethylated regions near the transcription start site and vary for genes with different dynamic responses to stress. Models trained on expression responses in a single genotype and promoter sequences provided lower performance when applied to other genotypes but this could be improved by using models trained on data from all three genotypes tested. The analysis of genes with cis-regulatory variation provides evidence for structural variants that result in presence/absence of transcription factor binding sites in creating variable responses. This study provides insights into cis-regulatory motifs for heat- and cold-responsive gene expression and defines a framework for developing models to predict expression responses across multiple genotypes.
PMID: 34735005
Plant Cell , IF:11.277 , 2021 Nov , V33 (11) : P3555-3573 doi: 10.1093/plcell/koab215
The CRY2-COP1-HY5-BBX7/8 module regulates blue light-dependent cold acclimation in Arabidopsis.
State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, 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.
Light and temperature are two key environmental factors that coordinately regulate plant growth and development. Although the mechanisms that integrate signaling mediated by cold and red light have been unraveled, the roles of the blue light photoreceptors cryptochromes in plant responses to cold remain unclear. In this study, we demonstrate that the CRYPTOCHROME2 (CRY2)-COP1-HY5-BBX7/8 module regulates blue light-dependent cold acclimation in Arabidopsis thaliana. We show that phosphorylated forms of CRY2 induced by blue light are stabilized by cold stress and that cold-stabilized CRY2 competes with the transcription factor HY5 to attenuate the HY5-COP1 interaction, thereby allowing HY5 to accumulate at cold temperatures. Furthermore, our data demonstrate that B-BOX DOMAIN PROTEIN7 (BBX7) and BBX8 function as direct HY5 targets that positively regulate freezing tolerance by modulating the expression of a set of cold-responsive genes, which mainly occurs independently of the C-repeat-binding factor pathway. Our study uncovers a mechanistic framework by which CRY2-mediated blue-light signaling enhances freezing tolerance, shedding light on the molecular mechanisms underlying the crosstalk between cold and light signaling pathways in plants.
PMID: 34427646
J Hazard Mater , IF:10.588 , 2021 Nov : P127826 doi: 10.1016/j.jhazmat.2021.127826
Low temperature tolerance is impaired by polystyrene nanoplastics accumulated in cells of barley (Hordeum vulgare L.) plants.
Crop Research Institute, Shandong Academy of Agricultural Sciences, Jinan 250100, China.; Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.; Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun 130024, China.; Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: lixiangnan@iga.ac.cn.
With increasing plastic consumption, the large amount of polystyrene nanoplastics (PS-NPs) in agricultural soil may not only directly affect the plant growth, but also indirectly affect the abiotic stress tolerance in crops. In this study, the barley (Hordeum vulgare L.) was irrigated with 2 g L(-1) PS-NPs (65.776 +/- 0.528 nm) solution for 7 days, then subjected to low temperature (2 ) for 24 h. The imaging of protoplasts indicated that polymethylmethacrylate nanoplastics could across the cell wall and accumulate in plant cells. The PS-NPs significantly decreased Rubisco activities and ATP production, hence limiting the photosynthetic carbon assimilation in barley under low temperature. The PS-NPs accumulated in cells also caused the significantly decreased activities of key enzymes involved in sucrolytic, glycolysis and starch metabolism pathways, including UDP-glucose pyrophorylase, ADP-Glucose pyrophosphorylase, phosphoglucomutase, glucose-6-phosphate dehydrogenase, phosphoglucoisomerase, fructokinase and phosphofructokinase. In addition, under low temperature, the PS-NPs presence significantly reduced the activities of superoxide dismutase, ascorbate peroxidase and catalase in chloroplasts, and significantly reduced the activities of ascorbate peroxidase and catalase in mitochondria. Thus, it is suggested that the PS-NPs accumulated in plant cells impaired the low temperature tolerance in barley mainly by the negative effects on photosynthetic carbon assimilation, carbohydrate metabolism and ROS homeostasis in sub-cellular level.
PMID: 34823951
Plant Biotechnol J , IF:9.803 , 2021 Nov doi: 10.1111/pbi.13745
CdWRKY2-mediated sucrose biosynthesis and CBF-signalling pathways coordinately contribute to cold tolerance in bermudagrass.
CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, China.; Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, China.; University of Chinese Academy of Sciences, Beijing, China.; College of Animal Science and Technology, Yangzhou University, Yangzhou, China.
Bermudagrass (Cynodon dactylon) is one of the most widely cultivated warm-season turfgrass species around the world. Cold stress has been a key environmental factor that adversely affects the growth, development, and geographical distribution of bermudagrass; however, the underlying mechanism of bermudagrass responsive to cold stress remains largely unexplored. Here, we identified a cold-induced WRKY transcription factor CdWRKY2 from bermudagrass and demonstrated its function in cold stress response. Overexpression of CdWRKY2 enhanced cold tolerance in transgenic Arabidopsis and bermudagrass hairy roots, while knocking down CdWRKY2 expression via virus-induced gene silencing increased cold susceptibility. RNA sequencing showed that overexpression of CdWRKY2 in Arabidopsis activated the expression of genes involved in sucrose synthesis and metabolism, including sucrose synthase 1 (AtSUS1) and sucrose phosphate synthase 2F (AtSPS2F). CdSPS1, the homology gene of AtSPS2F in bermudagrass, was subsequently proven to be the direct target of CdWRKY2 by yeast one-hybrid, electrophoretic mobility shift assay, and transient expression analysis. As expected, overexpression of CdSPS1 conferred cold tolerance in transgenic Arabidopsis plants, whereas silencing CdSPS1 expression enhanced cold sensitivity in bermudagrass. Besides, CdCBF1 whose expression was dramatically up-regulated in CdWRKY2-overexpressing bermudagrass hairy roots but down-regulated in CdWRKY2-silencing bermudagrass both under normal and cold stress conditions was confirmed as another target of CdWRKY2. Collectively, this study reveals that CdWRKY2 is a positive regulator in cold stress by targeting CdSPS1 and CdCBF1 promoters and activating their expression to coordinately mediate sucrose biosynthesis and CBF-signalling pathway, which provides valuable information for breeding cold-resistant bermudagrass through gene manipulation.
PMID: 34743386
Plant Physiol , IF:8.34 , 2021 Nov doi: 10.1093/plphys/kiab532
F-box protein EBF1 and transcription factor ABI5-like regulate banana fruit chilling-induced ripening disorder.
Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Engineering Research Center for Postharvest Technology of Horticultural Crops in South China, Ministry of Education, College of Horticulture, South China Agricultural University, Guangzhou 510642, CHINA.; College of Life Sciences, South China Agricultural University, Guangzhou 510642, China.
Cold stress adversely affects plant production, both qualitatively and quantitatively. Banana (Musa acuminata) is sensitive to cold stress and suffers chilling injury when stored under 11 degrees C, causing abnormal fruit softening. However, the mechanism underlying the abnormal fruit softening due to chilling injury remains obscure. This study uncovered the coordinated transcriptional mechanism of ethylene F-box protein (EBF1) and abscisic acid-insensitive 5 (ABI5)-like protein in regulating chilling-induced softening disorders of Feijiao banana. Cold stress severely inhibited the transcript and protein levels of EBF1, ABI5-like, and fruit softening-related genes. The ABI5-like protein bound to the promoters of key starch and cell wall degradation-related genes such as beta-amylase 8 (BAM8), pectate lyase 8 (PL8), and beta-D-xylosidase23-like (XYL23-like) and activated their activities. EBF1 physically interacted with ABI5-like and enhanced the transcriptional activity of the key starch and cell wall degradation-related genes but did not ubiquitinate or degrade ABI5-like protein. This promoted fruit ripening and ameliorated fruit chilling injury in a manner similar to the effect of exogenous abscisic acid treatment. The ectopic and transient overexpression of EBF1 and ABI5-like genes in tomato (Solanum lycopersicum) and Fenjiao banana accelerated fruit ripening and softening by promoting ethylene production, starch and cell wall degradation, and decreasing fruit firmness. EBF1 interacted with EIL4 but did not ubiquitinate or degrade EIL4, which is inconsistent with the typical role of EBF1/2 in Arabidopsis (Arabidopsis thaliana). These results collectively highlight that the interaction of EBF1 and ABI5-like controls starch and cell wall metabolism in banana, which is strongly inhibited by chilling stress, leading to fruit softening and ripening disorder.
PMID: 34791491
Plant Cell Environ , IF:7.228 , 2021 Nov , V44 (11) : P3616-3627 doi: 10.1111/pce.14138
HSP70-16 and VDAC3 jointly inhibit seed germination under cold stress in Arabidopsis.
Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China.; CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.; University of Chinese Academy of Sciences, Beijing, China.; School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China.; Department of Molecular Physiology, Max-Planck-Institute of Molecular Plant Physiology, Potsdam-Golm, Germany.
Abscisic acid (ABA) transport plays a crucial role in seed germination under unfavourable conditions such as cold stress. Both heat shock protein 70 (HSP70) and voltage-dependent anion channel (VDAC) protein are involved in cold stress responses in Arabidopsis. However, their roles in seed germination with regard to ABA signaling remain unknown. Here we demonstrated that Arabidopsis HSP70-16 and VDAC3 jointly suppress seed germination under cold stress conditions. At 4 degrees C, both HSP70-16 and VDAC3 facilitated the efflux of ABA from the endosperm to the embryo and thus inhibited seed germination. HSP70-16 interacted with VDAC3 on the plasma membrane and in the nucleus, and the interplay between HSP70-16 and VDAC3 activated the opening of the VDAC3 ion channel. Our work established a novel function of HSP70-16 in seed germination under cold stress and a possible association of VDAC3 activity with ABA transportation from endosperm to embryo under cold stress conditions. This study reveals that HSP70-16 interacts with VDAC3 and facilitates the opening of the VDAC3 ion channel, which influences ABA efflux from endosperm to embryo, thus negatively regulates seed germination under cold stress.
PMID: 34173257
Plant Cell Environ , IF:7.228 , 2021 Nov doi: 10.1111/pce.14231
Genotype-dependent contribution of CBF transcription factors to long-term acclimation to high light and cool temperature.
Howard Hughes Medical Institute, Dept. of Plant and Microbial Biology, University of California, Berkeley, CA, 94720-3102, USA.; Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, 80309-0334, USA.; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
When grown under cool temperature, winter annuals upregulate photosynthetic capacity as well as freezing tolerance. Here, the role of three cold-induced C-repeat-Binding Factor (CBF1-3) transcription factors in photosynthetic upregulation and freezing tolerance was examined in two Arabidopsis thaliana ecotypes originating from Italy (IT) or Sweden (SW), and their corresponding CBF1-3-deficient mutant lines it:cbf123 and sw:cbf123. Photosynthetic, morphological, and freezing-tolerance phenotypes as well as gene expression profiles were characterized in plants grown from seedling stage under different combinations of light level and temperature. Under high light and cool growth temperature (HLC), a greater role of CBF1-3 in IT versus SW was evident from both phenotypic and transcriptomic data, especially with respect to photosynthetic upregulation and freezing tolerance of whole plants. Overall, features of SW were consistent with a different approach to HLC acclimation than seen in IT, and an ability of SW to reach the new homeostasis through involvement of transcriptional controls other than CBF1-3. These results provide tools and direction for further mechanistic analysis of the transcriptional control of approaches to cold acclimation suitable for either persistence through brief cold spells or for maximization of productivity in environments with continuous low temperatures. This article is protected by copyright. All rights reserved.
PMID: 34799867
J Integr Plant Biol , IF:7.061 , 2021 Nov , V63 (11) : P1874-1887 doi: 10.1111/jipb.13161
The direct targets of CBFs: In cold stress response and beyond.
State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.
Cold acclimation in Arabidopsis thaliana triggers a significant transcriptional reprogramming altering the expression patterns of thousands of cold-responsive (COR) genes. Essential to this process is the C-repeat binding factor (CBF)-dependent pathway, involving the activity of AP2/ERF (APETALA2/ethylene-responsive factor)-type CBF transcription factors required for plant cold acclimation. In this study, we performed chromatin immunoprecipitation assays followed by deep sequencing (ChIP-seq) to determine the genome-wide binding sites of the CBF transcription factors. Cold-induced CBF proteins specifically bind to the conserved C-repeat (CRT)/dehydration-responsive elements (CRT/DRE; G/ACCGAC) of their target genes. A Gene Ontology enrichment analysis showed that 1,012 genes are targeted by all three CBFs. Combined with a transcriptional analysis of the cbf1,2,3 triple mutant, we define 146 CBF regulons as direct CBF targets. In addition, the CBF-target genes are significantly enriched in functions associated with hormone, light, and circadian rhythm signaling, suggesting that the CBFs act as key integrators of endogenous and external environmental cues. Our findings not only define the genome-wide binding patterns of the CBFs during the early cold response, but also provide insights into the role of the CBFs in regulating multiple biological processes of plants.
PMID: 34379362
Plant J , IF:6.417 , 2021 Nov , V108 (3) : P705-724 doi: 10.1111/tpj.15465
ERF108 from Poncirus trifoliata (L.) Raf. functions in cold tolerance by modulating raffinose synthesis through transcriptional regulation of PtrRafS.
Key Laboratory of Horticultural Plant Biology (MOE), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, China.
Ethylene-responsive factors (ERFs) are plant-specific transcription factors involved in cold stress response, and raffinose is known to accumulate in plants exposed to cold. However, it remains elusive whether ERFs function in cold tolerance by modulating raffinose synthesis. Here, we identified a cold-responsive PtrERF108 from trifoliate orange (Poncirus trifoliata (L.) Raf.), a cold-tolerant plant closely related to citrus. PtrERF108 is localized in the nucleus and has transcriptional activation activity. Overexpression of PtrERF108 conferred enhanced cold tolerance of transgenic lemon, whereas virus-induced gene silencing (VIGS)-mediated knockdown of PtrERF108 in trifoliate orange greatly elevated cold sensitivity. Transcriptome profiling showed that PtrERF108 overexpression caused extensive reprogramming of genes associated with signaling transduction, physiological processes and metabolic pathways. Among them, a raffinose synthase (RafS)-encoding gene, PtrRafS, was confirmed as a direct target of PtrERF108. RafS activity and raffinose content were significantly increased in PtrERF108-overexpressing transgenic plants, but prominently decreased in the VIGS plants under cold conditions. Meanwhile, exogenous replenishment of raffinose could recover the cold tolerance of PtrERF108-silenced plants, whereas VIGS-mediated knockdown of PtrRafS resulted in cold-sensitive phenotype. Taken together, the current results demonstrate that PtrERF108 plays a positive role in cold tolerance by modulation of raffinose synthesis via regulating PtrRafS. Our findings reveal a new transcriptional module composed of ERF108-RafS underlying cold-induced raffinose accumulation in plants.
PMID: 34398993
Int J Mol Sci , IF:5.923 , 2021 Nov , V22 (21) doi: 10.3390/ijms222111895
Bean and Pea Plastoglobules Change in Response to Chilling Stress.
Department of Plant Anatomy and Cytology, Faculty of Biology, Institute of Experimental Plant Biology and Biotechnology, University of Warsaw, I. Miecznikowa 1, PL-02096 Warsaw, Poland.; Department of Biophysics, Faculty of Biotechnology, University of Wroclaw, F. Joliot-Curie Street 14a, PL-50383 Wroclaw, Poland.; Department of Metabolic Regulation, Faculty of Biology, Institute of Biochemistry, University of Warsaw, I. Miecznikowa 1, PL-02096 Warsaw, Poland.
Plastoglobules (PGs) might be characterised as microdomains of the thylakoid membrane that serve as a platform to recruit proteins and metabolites in their spatial proximity in order to facilitate metabolic channelling or signal transduction. This study provides new insight into changes in PGs isolated from two plant species with different responses to chilling stress, namely chilling-tolerant pea (Pisum sativum) and chilling-sensitive bean (Phaseolus coccineus). Using multiple analytical methods, such as high-performance liquid chromatography and visualisation techniques including transmission electron microscopy and atomic force microscopy, we determined changes in PGs' biochemical and biophysical characteristics as a function of chilling stress. Some of the observed alterations occurred in both studied plant species, such as increased particle size and plastoquinone-9 content, while others were more typical of a particular type of response to chilling stress. Additionally, PGs of first green leaves were examined to highlight differences at this stage of development. Observed changes appear to be a dynamic response to the demands of photosynthetic membranes under stress conditions.
PMID: 34769326
Front Plant Sci , IF:5.753 , 2021 , V12 : P707127 doi: 10.3389/fpls.2021.707127
Identification of Glutathione Peroxidase Gene Family in Ricinus communis and Functional Characterization of RcGPX4 in Cold Tolerance.
College of Life Science and Food Engineering, Inner Mongolia Minzu University, Tongliao, China.; Horqin Plant Stress Biology Research Institute of Inner Mongolia Minzu University, Tongliao, China.; U.S. Department of Agriculture-Agricultural Research Service, Plant Genetics Research Unit, Donald Danforth Plant Science Center, Saint Louis, MO, United States.
Glutathione peroxidases (GPXs) protect cells against damage caused by reactive oxygen species (ROS) and play key roles in regulating many biological processes. Here, five GPXs were identified in the Ricinus communis genome. Phylogenetic analysis displayed that the GPXs were categorized into five groups. Conserved domain and gene structure analyses showed that the GPXs from different plant species harbored four highly similar motifs and conserved exon-intron arrangement patterns, indicating that their structure and function may have been conserved during evolution. Several abiotic stresses and hormone-responsive cis-acting elements existed in the promoters of the RcGPXs. The expression profiles indicated that the RcGPXs varied substantially, and some RcGPXs were coordinately regulated under abiotic stresses. Overexpression of RcGPX4 in Arabidopsis enhanced cold tolerance at seed germination but reduced freezing tolerance at seedlings. The expression of abscisic acid (ABA) signaling genes (AtABI4 and AtABI5), ABA catabolism genes (AtCYP707A1 and AtCYP707A2), gibberellin acid (GA) catabolism gene (AtGA2ox7), and cytokinin (CTK)-inducible gene (AtARR6) was regulated in the seeds of transgenic lines under cold stress. Overexpression of RcGPX4 can disturb the hydrogen peroxide (H2O2) homeostasis through the modulation of some antioxidant enzymes and compounds involved in the GSH-ascorbate cycle in transgenic plants. Additionally, RcGPX4 depended on the MAPK3-ICE1-C-repeat-binding factor (CBF)-COR signal transduction pathway and ABA-dependent pathway to negatively regulate the freezing tolerance of transgenic plants. This study provides valuable information for understanding the potential function of RcGPXs in regulating the abiotic stress responses of castor beans.
PMID: 34804079
J Agric Food Chem , IF:5.279 , 2021 Nov , V69 (45) : P13398-13415 doi: 10.1021/acs.jafc.1c04316
tae-miR399-UBC24 Module Enhances Freezing Tolerance in Winter Wheat via a CBF Signaling Pathway.
College of Life Science, Northeast Agricultural University, Harbin 150030, P.R. China.
Although the regulation of Pi homeostasis by miR399 has been studied in various plant species, its underlying molecular mechanism in response to freezing stress is still poorly understood. In this work, we found that the expression of tae-miR399 and its target gene TaUBC24 in the tillering nodes of the strong cold-resistant winter wheat cultivar Dongnongdongmai1 (Dn1) was not only significantly altered after severe winters but also responsive to short-term freezing stress. TaUBC24 physically interacted with TaICE1. Enhanced freezing tolerance was observed for tae-miR399-overexpressing Arabidopsis lines. Under freezing stress, overexpression of tae-miR399 ultimately decreased the expression of AtUBC24, inhibiting the degradation of AtICE1, which increased the expression of genes involved in the CBF signaling pathway and starch metabolism and promoted the activities of antioxidant enzymes. These results will improve our understanding of the molecular mechanism through which the miR399-UBC24 module plays a cardinal role in regulating plant freezing stress tolerance through mediation of downstream pathways.
PMID: 34729981
Physiol Plant , IF:4.5 , 2021 Nov , V173 (3) : P1263-1279 doi: 10.1111/ppl.13522
CGFS-type glutaredoxin mutations reduce tolerance to multiple abiotic stresses in tomato.
Department of Horticulture and Natural Resources, Kansas State University, Manhattan, Kansas, USA.; Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China.
Sessile organisms such as plants have adopted diverse reactive oxygen species (ROS) scavenging mechanisms to mitigate damage under abiotic stress conditions. Though CGFS-type glutaredoxin (GRX) genes are important regulators of ROS homeostasis, each of their functions in crop plants have not yet been well understood. We performed a targeted mutagenesis analysis of four CGFS-type GRXs (SlGRXS14, SlGRXS15, SlGRXS16, and SlGRXS17) in tomato plants (Solanum lycopersicum) using a multiplex clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 system and found that Slgrxs mutants were more sensitive to various abiotic stresses compared with the wild-type tomatoes. Slgrxs15 mutants were embryonic lethal. Single, double, and triple combinations of Slgrxs14, 16, and 17 mutants were examined under heat, chilling, drought, heavy metal toxicity, nutrient deficiency, and short photoperiod stresses. Slgrxs14 and 17 mutants showed hypersensitivity to almost all stresses while Slgrxs16 mutants were affected by chilling stress and showed milder sensitivity to other stresses. Additionally, Slgrxs14 and 17 mutants showed delayed flowering time. Our results indicate that the CGFS-type SlGRXs have specific roles against abiotic stresses, providing valuable resources to develop tomato and, possibly, other crop species that are tolerant to multiple abiotic stresses by genetic engineering.
PMID: 34392538
Physiol Plant , IF:4.5 , 2021 Nov , V173 (3) : P1105-1119 doi: 10.1111/ppl.13506
Assessing growth, frost tolerance, and acclimation of pine seedlings with contrasted dormancy strategies as influenced by organic nitrogen supply.
Departamento de Sistemas y Recursos Naturales, ETS Ingenieros de Montes, Forestal y del Medio Natural, Universidad Politecnica de Madrid, Madrid, Spain.; Forest Plantations and Agroforestry Program, Campo Experimental Valle del Guadiana, Instituto Nacional de Investigaciones Forestales, Agricolas y Pecuarias (INIFAP), Durango, Mexico.; Forest Ecology and Restoration Group, Departamento de Ciencias de la Vida, Universidad de Alcala, Madrid, Spain.
Freezing stress is a critical environmental factor affecting survival, distribution, and evolution of plants. Although there is evidence that nitrogen (N) affects frost tolerance of juvenile conifers, the magnitude and direction of such effect can diverge among species. The influence of the N source on frost tolerance has been barely studied. Particularly, how organic N sources could affect the cold acclimation dynamics of seedlings is poorly understood. We studied morpho-physiological responses to organic N supply (amino acids) in comparison to inorganic N in seedlings of two Mediterranean pine species: Pinus halepensis and P. sylvestris. Fertilization was applied at low and high N doses (30 and 130 mg N seedling(-1) ) in the first growing season. Then, tolerance of seedlings to freezing stress was evaluated through the cold season. This study confirmed that organic N supply promotes growth of both species as effectively as inorganic N sources. At low N availability, seedlings had acute phosphorus deficiencies when grown with inorganic N, but not with organic N. Likewise, high organic-N availability improved chlorophylls concentration. Both species increased their frost tolerance through time, especially during late autumn. Although organic N supply did not show clear benefits on frost tolerance, it seemed to enhance cold acclimation via increases of compatible solutes, such as soluble sugars and proline, particularly in P. halepensis. Thus, the effects of organic N supply could depend on the extent that such osmolytes contribute to the dormancy strategy of the species. Other species-specific mechanisms to cope with freezing stress are further discussed.
PMID: 34287917
Sci Rep , IF:4.379 , 2021 Nov , V11 (1) : P22136 doi: 10.1038/s41598-021-01703-7
The physiological response of different tobacco varieties to chilling stress during the vigorous growing period.
College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715, China.; College of Tobacco Science, Yunnan Agricultural University, Kunming, 650201, China.; Yunnan Academy of Tobacco Agricultural Sciences, Kunming, 650021, Yunnan, China. zoucongmingzcm@163.com.; College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715, China. xiexy8009@163.com.
Tobacco is be sensitively affected by chilling injury in the vigorous growth period, which can easily lead to tobacco leaf browning during flue-curing and quality loss, however, the physiological response of tobacco in the prosperous period under low temperature stress is unclear. The physiological response parameters of two tobacco varieties to low temperature stress were determined. The main results were as follows: 1 in circle For tobacco in the vigorous growing period subjected to low-temperature stress at 4-16 degrees C, the tissue structure of chloroplast changed and photosynthetic pigments significantly decreased compared with each control with the increase of intensity of low-temperature stress. 2 in circle For tobacco in the vigorous growing period at 10-16 degrees C, antioxidant capacity of the protective enzyme system, osmotic adjustment capacity of the osmotic adjusting system and polyphenol metabolism in plants gradually increased due to induction of low temperature with the increase of intensity of low-temperature stress. 3 in circle Under low-temperature stress at 4 degrees C, the protective enzyme system, osmotic adjusting system and polyphenol metabolism of the plants played an insignificant role in stress tolerance, which cannot be constantly enhanced based on low-temperature resistance at 10 degrees C. This study confirmed that under the temperature stress of 10-16 degrees C, the self-regulation ability of tobacco will be enhanced with the deepening of low temperature stress, but there is a critical temperature between 4 and 10 degrees C. The self-regulation ability of plants under low temperature stress will be inhibited.
PMID: 34764409
Plant Physiol Biochem , IF:4.27 , 2021 Nov , V169 : P224-235 doi: 10.1016/j.plaphy.2021.11.027
Identification and function analysis of bHLH genes in response to cold stress in sweetpotato.
Xuzhou Sweetpotato Research Center, Xuzhou Institute of Agricultural Sciences, Key Laboratory of Sweetpotato Biology and Genetic Breeding, Ministry of Agriculture, Xuzhou, China.; Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Daejeon, South Korea.; Liaoning Academy of Agricultural Sciences, Shenyang, China.; Cereal Crops Research Institute, Henan Academy of Agricultural Sciences, Postgraduate T&R Base of Zhengzhou University, Zhengzhou, China; School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China.; School of Life Sciences, Jiangsu Normal University, Xuzhou, China.; Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Daejeon, South Korea. Electronic address: sskwak@kribb.re.kr.; Xuzhou Sweetpotato Research Center, Xuzhou Institute of Agricultural Sciences, Key Laboratory of Sweetpotato Biology and Genetic Breeding, Ministry of Agriculture, Xuzhou, China. Electronic address: zhonghoutang@sina.com.
Basic/helix-loop-helix (bHLH) transcription factors are involved in various metabolic and physiological processes in plants. Sweetpotato (Ipomoea batatas (L.) Lam.) is an important crop in China but is highly susceptible to cold stress. However, little information on the bHLH gene family is available, and the function of this family in response to cold stress has not been revealed in sweetpotato. Here, 110 IbbHLHs were identified and classified into 17 categories based on phylogenetic relationships, conserved motifs and gene structure analyses. Except for 5 IbbHLHs, 90 IbbHLHs were putative E-box-binding proteins including 70 IbbHLHs belonging to G-box, whereas 15 IbbHLHs were putative non-E box-binding proteins based on DNA-binding analysis. In total, 37 pairs of segmental duplicated genes and 5 pairs of tandem duplication genes were identified within the IbbHLH gene family. The transcript level of 20 IbbHLHs was regulated by cold stress based on RNA-seq data, and 8 genes were selected for further quantitative real-time PCR (qRT-PCR) analysis. IbHLH8 and IbHLH92 are involved in network interaction with several genes related to abiotic and biotic stresses under cold treatment. IbbHLH79, an ICE1-like gene, was isolated and overexpressed in sweetpotato. The IbbHLH79 protein can activate the CBF (C-repeat Binding Factor) pathway, and IbbHLH79-overexpressing transgenic plants display enhanced cold tolerance. Taken together, these results provide valuable information on the IbbHLH gene family; in addition, several IbbHLHs may regulate cold stress, and the results suggest IbbHLH79 will be useful for molecular breeding of enhanced cold tolerance in sweetpotato.
PMID: 34808465
Plant Physiol Biochem , IF:4.27 , 2021 Nov , V169 : P190-202 doi: 10.1016/j.plaphy.2021.11.017
Different G6PDH isoforms show specific roles in acclimation to cold stress at various growth stages of barley (Hordeum vulgare) and Arabidopsis thaliana.
Department of Biology, University of Naples Federico II, Complesso Monte Sant'Angelo, Via Cinthia, 80126, Napoli, Italy.; Department of Biology, University of Naples Federico II, Complesso Monte Sant'Angelo, Via Cinthia, 80126, Napoli, Italy. Electronic address: sergio.esposito@unina.it.
Low temperatures (0-10 degrees C) represent a major physiological stress for plants, negatively affecting both their growth rates and overall growth. Cold stress may induce a wide range of negative physiological effects, from oxidative stress to photosynthetic damage. We investigated the effects of low temperatures in two different model plants, Arabidopsis thaliana and Hordeum vulgare. We tested whether the oxidative pentose phosphate pathway (OPPP) is involved in the increase of reductants' levels needed to counteract oxidative stress induced by cold. The expression, occurrence, and activity of different glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) isoforms during cold stress and plant recovery from low temperatures, were measured at different growth stages from early germinated to mature pot-grown plants. Our results showed plants exhibited changes in different stress markers; ascorbate peroxidase - APX, catalase - CAT, proline, malondialdehyde, H2O2, NADPH/NADP(+). We found that a major role in cold acclimation for cytosolic- and peroxisome-located G6PDHs, and different roles for plastidial/chloroplastic isoforms. This suggests that G6PDH isoforms may regulate redox homeostasis in low temperatures, in order to support the increased and continued demand of reductants during both cold stress and recovery stages. Furthermore, we found a significant involvement of (6PGDH), strengthening the idea that the contribution of the whole oxidative pentose phosphate pathway (OPPP) is required to sustain reductant supply under cold stress.
PMID: 34801973
BMC Plant Biol , IF:4.215 , 2021 Nov , V21 (1) : P542 doi: 10.1186/s12870-021-03317-7
Identification of cold tolerance QTLs at the bud burst stage in 211 rice landraces by GWAS.
Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education, Nanchang, 330045, Jiangxi Province, China.; Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Nanchang, 330045, Jiangxi Province, China.; Agricultural Genomics Institute in Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518000, Guangdong Province, China.; Peking University Institute of Advanced Agricultural Sciences, Weifang, 261325, Shandong Province, China.; Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education, Nanchang, 330045, Jiangxi Province, China. hhhua64@163.com.; Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Nanchang, 330045, Jiangxi Province, China. hhhua64@163.com.; Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education, Nanchang, 330045, Jiangxi Province, China. jmbian81@126.com.; Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Nanchang, 330045, Jiangxi Province, China. jmbian81@126.com.
BACKGROUND: Rice is a crop that is very sensitive to low temperature, and its morphological development and production are greatly affected by low temperature. Therefore, understanding the genetic basis of cold tolerance in rice is of great significance for mining favorable genes and cultivating excellent rice varieties. However, there have been limited studies focusing on cold tolerance at the bud burst stage; therefore, considerable attention should be given to the genetic basis of cold tolerance at this stage. RESULTS: In this study, a natural population consisting of 211 rice landraces collected from 15 provinces in China and other countries was used for the first time to evaluate cold tolerance at the bud burst stage. Population structure analysis showed that this population was divided into two groups and was rich in genetic diversity. Our evaluation results confirmed that japonica rice was more tolerant to cold at the bud burst stage than indica rice. A genome-wide association study (GWAS) was performed with the phenotypic data of 211 rice landraces and a 36,727 SNP dataset under a mixed linear model. Twelve QTLs (P < 0.0001) were identified for the seedling survival rate (SR) after treatment at 4 degrees C, in which there were five QTLs (qSR2-2, qSR3-1, qSR3-2, qSR3-3 and qSR9) that were colocalized with those from previous studies and seven QTLs (qSR2-1, qSR3-4, qSR3-5, qSR3-6, qSR3-7, qSR4 and qSR7) that were reported for the first time. Among these QTLs, qSR9, harboring the most significant SNP, explained the most phenotypic variation. Through bioinformatics analysis, five genes (LOC_Os09g12440, LOC_Os09g12470, LOC_Os09g12520, LOC_Os09g12580 and LOC_Os09g12720) were identified as candidates for qSR9. CONCLUSION: This natural population consisting of 211 rice landraces combined with high-density SNPs will serve as a better choice for identifying rice QTLs/genes in the future, and the detected QTLs associated with cold tolerance at the bud burst stage in rice will be conducive to further mining favorable genes and breeding rice varieties under cold stress.
PMID: 34800993
BMC Plant Biol , IF:4.215 , 2021 Nov , V21 (1) : P532 doi: 10.1186/s12870-021-03300-2
Physiological and biochemical responses of strawberry crown and leaf tissues to freezing stress.
Department of Horticultural Science, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.; Horticultural Research Department, Kurdistan Agricultural and Natural Resources Research and Education Center, AREEO, Sanandaj, Iran. f.karami@areeo.ac.ir.; Department of Horticultural Sciences, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, Iran.; Horticultural Research Department, Kurdistan Agricultural and Natural Resources Research and Education Center, AREEO, Sanandaj, Iran.; Department of Horticultural Science, NC State University, Raleigh, NC, USA.; Department of Horticultural Sciences, Faculty of Agriculture, University of Maragheh, Maragheh, Iran.; Department of Plant Sciences, College of Agricultural and Marine Sciences, Sultan Qaboos University, 123, Al-Khoud, Oman.
BACKGROUND: In northern Iran and other cold regions, winter freezing injury and resultant yield instability are major limitations to strawberry production. However, there is scarcity of information on the physiological and biochemical responses of strawberry cultivars to freezing stress. This study aimed to investigate the physiological and biochemical responses of strawberry cultivars (Tennessee Beauty, Blakemore, Kurdistan, Queen Elisa, Chandler, Krasnyy Bereg, and Yalova) to different freezing temperature treatments (- 5, - 10, - 15, - 20, and - 25 degrees C) under controlled conditions. RESULTS: All measured physiological and biochemical features were significantly affected by the interaction effect between low temperatures and cultivars. Tennessee Beauty showed the highest RWC at - 25 degrees C. The highest Fv/Fm was observed in Queen Elisa. Krasnyy Bereg had the least freezing injury (FI) in crown and leaf, while Yalova and Chandler showed the highest crown and leaf FI, respectively. At - 20 to - 25 degrees C, the highest carbohydrates contents of crown and leaf were noted in Blakemore and Krasnyy Bereg cultivars, respectively. The Yalova showed the highest protein content in both crown and leaf tissues at - 25 degrees C. The Tennessee Beauty and Blackmore cultivars showed the highest proline in crowns and leaves at - 15 degrees C, respectively. The highest ThioBarbituric Acid Reactive Substances (TBARS) contents in the crown and leaf were observed in Kurdistan and Queen Elisa, respectively. Queen Elisa and Krasnyy Bereg cultivars showed SOD and POD peaks in the crown at - 15 degrees C, respectively. CONCLUSION: Freezing stress was characterized by decreased Fv/Fm and RWC, and increased FI, TBARS, total carbohydrates, total proteins, proline content, and antioxidant enzyme activity. The extent of changes in above mentioned traits was cultivar dependent. FI and TBARS were the best traits among destructive parameters for evaluating freezing tolerance. Moreover, maximum quantum yield of PSII (Fv/Fm index), as non-destructive parameters, showed a significant efficiency in rapid assessment for screening of freezing tolerant strawberry cultivars. The cultivars Krasnyy Bereg, Queen Elisa, and Kurdistan were the most tolerant cultivars to freezing stress. These cultivars can be used as parents in breeding programs to develop new freezing tolerant cultivars.
PMID: 34773991
Genes (Basel) , IF:4.096 , 2021 Nov , V12 (11) doi: 10.3390/genes12111818
Gene Expression Profiles Suggest a Better Cold Acclimation of Polyploids in the Alpine Species Ranunculus kuepferi (Ranunculaceae).
Department of Systematics, Biodiversity and Evolution of Plants (with Herbarium), Georg-August-Universitat Gottingen, 37073 Gottingen, Germany.; Department of Botany and Molecular Evolution, Senckenberg Research Institute, 60325 Frankfurt am Main, Germany.
Alpine habitats are shaped by harsh abiotic conditions and cold climates. Temperature stress can affect phenotypic plasticity, reproduction, and epigenetic profiles, which may affect acclimation and adaptation. Distribution patterns suggest that polyploidy seems to be advantageous under cold conditions. Nevertheless, whether temperature stress can induce gene expression changes in different cytotypes, and how the response is initialized through gene set pathways and epigenetic control remain vague for non-model plants. The perennial alpine plant Ranunculus kuepferi was used to investigate the effect of cold stress on gene expression profiles. Diploid and autotetraploid individuals were exposed to cold and warm conditions in climate growth chambers and analyzed via transcriptome sequencing and qRT-PCR. Overall, cold stress changed gene expression profiles of both cytotypes and induced cold acclimation. Diploids changed more gene set pathways than tetraploids, and suppressed pathways involved in ion/cation homeostasis. Tetraploids mostly activated gene set pathways related to cell wall and plasma membrane. An epigenetic background for gene regulation in response to temperature conditions is indicated. Results suggest that perennial alpine plants can respond to temperature extremes via altered gene expression. Tetraploids are better acclimated to cold conditions, enabling them to colonize colder climatic areas in the Alps.
PMID: 34828424
BMC Genomics , IF:3.969 , 2021 Nov , V22 (1) : P800 doi: 10.1186/s12864-021-08104-0
Genome-wide analysis of Dof transcription factors and their response to cold stress in rice (Oryza sativa L.).
Institute of Plant Protection, Heilongjiang Academy of Agricultural Sciences, No. 368 Xuefu Road, Nangang District, 150086, Harbin, China.; Institute of Plant Protection, Heilongjiang Academy of Agricultural Sciences, No. 368 Xuefu Road, Nangang District, 150086, Harbin, China. mqlhlcn@126.com.; Institute of Farming and Cultivation, Heilongjiang Academy of Agricultural Sciences, 150086, Harbin, China.
BACKGROUND: Rice (Oryza sativa L.) is a food crop for humans worldwide. However, temperature has an effect during the vegetative and reproductive stages. In high-latitude regions where rice is cultivated, cold stress is a major cause of yield loss and plant death. Research has identified a group of plant-specific transcription factors, DNA binding with one zinc fingers (DOFs), with a diverse range of functions, including stress signaling and stress response during plant growth. The aim of this study was to identify Dof genes in two rice subspecies, indica and japonica, and screen for Dof genes that may be involved in cold tolerance during plant growth. RESULTS: A total of 30 rice Dofs (OsDofs) were identified using bioinformatics and genome-wide analyses and phylogenetically analyzed. The 30 OsDOFs were classified into six subfamilies, and 24 motifs were identified based on protein sequence alignment. The chromosome locations of OsDofs were determined and nine gene duplication events were identified. A joint phylogenetic analysis was performed on DOF protein sequences obtained from four monocotyledon species to examine the evolutionary relationship of DOF proteins. Expression profiling of OsDofs from two japonica cultivars (Longdao5, which is cold-tolerant, and Longjing11, which is cold-sensitive) revealed that OsDof1 and OsDof19 are cold-inducible genes. We examined the seed setting rates in OsDof1- and OsDof19-overexpression and RNAi lines and found that OsDof1 showed a response to cold stress. CONCLUSIONS: Our investigation identified OsDof1 as a potential target for genetic breeding of rice with enhanced cold tolerance.
PMID: 34742240
Plants (Basel) , IF:3.935 , 2021 Nov , V10 (11) doi: 10.3390/plants10112369
Carrot AOX2a Transcript Profile Responds to Growth and Chilling Exposure.
MED-Mediterranean Institute for Agriculture, Environment and Development, Instituto de Investigacao e Formacao Avancada, Universidade de Evora, Polo da Mitra, Ap. 94, 7006-554 Evora, Portugal.; LEAF-Linking Landscape, Environment, Agriculture and Food Research Center, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal.
Alternative oxidase (AOX) is a key enzyme of the alternative respiration, known to be involved in plant development and in response to various stresses. To verify the role of DcAOX1 and DcAOX2a genes in carrot tap root growth and in response to cold stress, their expression was analyzed in two experiments: during root growth for 13 weeks and in response to a cold challenge trial of 7 days, in both cases using different carrot cultivars. Carrot root growth is initially characterized by an increase in length, followed by a strong increase in weight. DcAOX2a presented the highest expression levels during the initial stages of root growth for all cultivars, but DcAOX1 showed no particular trend in expression. Cold stress had a negative impact on root growth, and generally up-regulated DcAOX2a with no consistent effect on DcAOX1. The identification of cis-acting regulatory elements (CAREs) located at the promoters of both genes showed putative sequences involved in cold stress responsiveness, as well as growth. However, DcAOX2a promoter presented more CAREs related to hormonal pathways, including abscisic acid and gibberellins synthesis, than DcAOX1. These results point to a dual role of DcAOX2a on carrot tap root secondary growth and cold stress response.
PMID: 34834732
J Plant Physiol , IF:3.549 , 2021 Nov , V266 : P153534 doi: 10.1016/j.jplph.2021.153534
Small signaling molecules in plant response to cold stress.
College of Life Sciences, Northwest Normal University, Lanzhou, 730070, China.; MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China.; Qinghai Provincial Key Laboratory of Medicinal Plant and Animal Resources of Qinghai-Tibet Plateau, School of Life Sciences, Qinghai Normal University, Xining, 810008, China.; State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining, 810016, China.; MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China. Electronic address: qiuqsh@lzu.edu.cn.
Cold stress is one of the harsh environmental stresses that adversely affect plant growth and crop yields in the Qinghai-Tibet Plateau. However, plants have evolved mechanisms to overcome the impact of cold stress. Progress has been made in understanding how plants perceive and transduce low-temperature signals to tolerate cold stress. Small signaling molecules are crucial for cellular signal transduction by initiating the downstream signaling cascade that helps plants to respond to cold stress. These small signaling molecules include calcium, reactive oxygen species, nitric oxide, hydrogen sulfide, cyclic guanosine monophosphate, phosphatidic acid, and sphingolipids. The small signaling molecules are involved in many aspects of cellular and physiological functions, such as inducing gene expression and activating hormone signaling, resulting in upregulation of the antioxidant enzyme activities, osmoprotectant accumulation, malondialdehyde reduction, and photosynthesis improvement. We summarize our current understanding of the roles of the small signaling molecules in cold stress in plants, and highlight their crosstalk in cold signaling transduction. These discoveries help us understand how the plateau plants adapt to the severe alpine environment as well as to develop new crops tolerating cold stress in the Qinghai-Tibet Plateau.
PMID: 34601338
Protoplasma , IF:3.356 , 2021 Nov , V258 (6) : P1335-1346 doi: 10.1007/s00709-021-01682-6
Winter survival of the unicellular green alga Micrasterias denticulata: insights from field monitoring and simulation experiments.
Department of Biosciences, University of Salzburg, Hellbrunnerstrasse 34, 5020, Salzburg, Austria.; Institute of Pharmacology, University of Linz, Huemerstrasse 3-5, 4020, Linz, Austria.; Department of Biosciences, University of Salzburg, Hellbrunnerstrasse 34, 5020, Salzburg, Austria. mail@o.buchner.co.uk.; Department of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestrasse 15, 6020, Innsbruck, Austria.
Peat bog pools around Tamsweg (Lungau, Austria) are typical habitats of the unicellular green alga Micrasterias denticulata. By measurement of water temperature and irradiation throughout a 1-year period (2018/2019), it was intended to assess the natural environmental strain in winter. Freezing resistance of Micrasterias cells and their ability to frost harden and become tolerant to ice encasement were determined after natural hardening and exposure to a cold acclimation treatment that simulated the natural temperature decrease in autumn. Transmission electron microscopy (TEM) was performed in laboratory-cultivated cells, after artificial cold acclimation treatment and in cells collected from field. Throughout winter, the peat bog pools inhabited by Micrasterias remained unfrozen. Despite air temperature minima down to -17.3 degrees C, the water temperature was mostly close to +0.8 degrees C. The alga was unable to frost harden, and upon ice encasement, the cells showed successive frost damage. Despite an unchanged freezing stress tolerance, significant ultrastructural changes were observed in field-sampled cells and in response to the artificial cold acclimation treatment: organelles such as the endoplasmic reticulum and thylakoids of the chloroplast showed distinct membrane bloating. Still, in the field samples, the Golgi apparatus appeared in an impeccable condition, and multivesicular bodies were less frequently observed suggesting a lower overall stress strain. The observed ultrastructural changes in winter and after cold acclimation are interpreted as cytological adjustments to winter or a resting state but are not related to frost hardening as Micrasterias cells were unable to improve their freezing stress tolerance.
PMID: 34304308
J Biotechnol , IF:3.307 , 2021 Dec , V342 : P102-113 doi: 10.1016/j.jbiotec.2021.10.012
Inhibition of the JAZ1 gene causes activation of camalexin biosynthesis in Arabidopsis callus cultures.
Federal Scientific Center of the East Asia Terrestrial Biodiversity of the Far East Branch of Russian Academy of Sciences, Vladivostok 690022, Russia. Electronic address: makhazen@biosoil.ru.; Federal Scientific Center of the East Asia Terrestrial Biodiversity of the Far East Branch of Russian Academy of Sciences, Vladivostok 690022, Russia.
Indole alkaloid camalexin has potential medicinal properties such as suppressing the viability of leukemic but not normal cells. Camalexin is not produced in plants and an external factor is required to activate its biosynthesis. In this work, we stimulated camalexin biosynthesis in Arabidopsis calli by blocking one of repressors of the jasmonate pathway, the jasmonate ZIM-domain protein 1 (JAZ1) by using amiRNA targeting JAZ1 gene transcripts. Inhibition of the JAZ1 gene led to an increase in camalexin content from trace amounts in control culture to 9 microg/g DW in the jaz1 line without affecting growth. In addition, JAZ1 silencing enhanced tolerance to cold stress with simultaneous increasing camalexin content up to 30 microg/g DW. Real-time quantitative PCR determination of marker gene expression showed that effects caused by the JAZ1 silencing might be realized through crosslinking JA, ROS, and abscisic acid signaling pathways. Thus, targeting the distal components of signaling pathways can be suggested as a tool for bioengineering of secondary metabolism, along with standard techniques for targeting biosynthetic genes or genes encoding transcription factors.
PMID: 34736953
Yi Chuan , IF:3.271 , 2021 Nov , V43 (11) : P1078-1087 doi: 10.16288/j.yczz.21-217
Transcription factor OsMADS25 improves rice tolerance to cold stress.
Hunan Provincial Key Laboratory of Rice Stress Biology, College of Agriculture, Hunan Agricultural University, Changsha 410128, China.; State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha 410125, China.; Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China.
Cold stress is the limiting factor of rice growth and production, and it is important to clone cold stress tolerant genes and cultivate cold tolerance rice varieties. The MADS transcription factors play an important role in abiotic stress signaling in rice. This study showed that OsMADS25 was up-regulated by low temperature and abscisic acid (ABA), suggesting that OsMADS25 may be involved in ABA-dependent signaling. The OsMADS25 overexpression vector, pCambia1300-221-OsMADS25-Flag, was constructed and introduced into the rice variety Zhonghua 11 (ZH11) through Agrobacterium tumefacian-mediated genetic transformation. Two homozygous lines with high expression levels were selected for phenotypic identification. OsMADS25 overexpression lines show significantly improved cold stress tolerance and the sensitivity to ABA at the seedling stage of rice. Reactive oxygen species (ROS) was detected by diaminobenzidine (DAB) staining and nitroblue tetrazolium (NBT) staining. After treatment with cold stress, little ROS accumulation was observed in OsMADS25 overexpression lines compared to wild-type ZH11. In conclusion, OsMADS25 plays a role in scavenging reactive oxygen species (ROS) and could improve rice tolerance to cold stress involved in ABA-dependent pathway.
PMID: 34815210
PLoS One , IF:3.24 , 2021 , V16 (11) : Pe0259455 doi: 10.1371/journal.pone.0259455
Joint transcriptomic and metabolomic analysis reveals the mechanism of low-temperature tolerance in Hosta ventricosa.
College of Agriculture, Jilin Agricultural Science and Technology University, Jilin, PR China.
Hosta ventricosa is a robust ornamental perennial plant that can tolerate low temperatures, and which is widely used in urban landscaping design in Northeast China. However, the mechanism of cold-stress tolerance in this species is unclear. A combination of transcriptomic and metabolomic analysis was used to explore the mechanism of low-temperature tolerance in H. ventricosa. A total of 12 059 differentially expressed genes and 131 differentially expressed metabolites were obtained, which were mainly concentrated in the signal transduction and phenylpropanoid metabolic pathways. In the process of low-temperature signal transduction, possibly by transmitting Ca2+ inside and outside the cell through the ion channels on the three cell membranes of COLD, CNGCs and CRLK, H. ventricosa senses temperature changes and stimulates SCRM to combine with DREB through the MAPK signal pathway and Ca2+ signal sensors such as CBL, thus strengthening its low-temperature resistance. The pathways of phenylpropanoid and flavonoid metabolism represent the main mechanism of low-temperature tolerance in this species. The plant protects itself from low-temperature damage by increasing its content of genistein, scopolentin and scopolin. It is speculated that H. ventricosa can also adjust the content ratio of sinapyl alcohol and coniferyl alcohol and thereby alter the morphological structure of its cell walls and so increase its resistance to low temperatures.When subjected to low-temperature stress, H. ventricosa perceives temperature changes via COLD, CNGCs and CRLK, and protection from low-temperature damage is achieved by an increase in the levels of genistein, scopolentin and scopolin through the pathways of phenylpropanoid biosynthesis and flavonoid biosynthesis.
PMID: 34731224
Ecotoxicology , IF:2.823 , 2021 Nov , V30 (9) : P1826-1840 doi: 10.1007/s10646-021-02483-6
Comparative physiological and proteomic analyses of mangrove plant Kandelia obovata under cold stress.
State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China.; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, China.; Innovation Academy of South China Sea Ecology and Environmental Engineering Chinese Academy of Sciences, Guangzhou, 510301, China.; State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China. yswang@scsio.ac.cn.; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, China. yswang@scsio.ac.cn.; Innovation Academy of South China Sea Ecology and Environmental Engineering Chinese Academy of Sciences, Guangzhou, 510301, China. yswang@scsio.ac.cn.; Daya Bay Marine Biology Research Station, Chinese Academy of Sciences, Shenzhen, 518121, China. yswang@scsio.ac.cn.; Daya Bay Marine Biology Research Station, Chinese Academy of Sciences, Shenzhen, 518121, China.
Cold events had broadly affected the survival and geographic distribution of mangrove plants. Kandelia obovata, has an excellent cold tolerance as a true halophyte and widespread mangrove species. In this study, physiological characters and comparative proteomics of leaves of K. obovata were performed under cold treatment. The physiological analysis showed that K. obovata could alleviate its cold-stress injuries through increasing the levels of antioxidants, the activities of related enzymes, as well as osmotic regulation substances (proline). It was detected 184 differentially expressed protein spots, and of 129 (70.11%) spots were identified. These proteins have been involved in several pathways such as the stress and defense, photosynthesis and photorespiration, signal transduction, transcription factors, protein biosynthesis and degradation, molecular chaperones, ATP synthesis, the tricarboxylic acid (TCA) cycle and primary metabolisms. The protein post-translational modification may be a common phenomenon and plays a key role in cold-response process in K. obovata. According to our precious work, a schematic diagram was drawn for the resistance or adaptation strategy of mangrove plants under cold stress. This study provided valuable information to understand the mechanism of cold tolerance of K. obovata.
PMID: 34618290
Mol Biol Rep , IF:2.316 , 2021 Nov doi: 10.1007/s11033-021-06874-0
Phosphoproteomics of cold stress-responsive mechanisms in Rhododendron chrysanthum.
Jilin Provincial Key Laboratory of Plant Resource Science and Green Production, Jilin Normal University, Siping, 136000, China.; Jilin Provincial Key Laboratory of Plant Resource Science and Green Production, Jilin Normal University, Siping, 136000, China. xuhongwei@jlnu.edu.cn.; Jilin Provincial Key Laboratory of Plant Resource Science and Green Production, Jilin Normal University, Siping, 136000, China. zhouxiaofu@jlnu.edu.cn.
BACKGROUND: As an alpine plant, Rhododendron chrysanthum (R. chrysanthum) has evolved cold resistance mechanisms and become a valuable plant resource with the responsive mechanism of cold stress. METHODS AND RESULTS: We adopt the phosphoproteomic and proteomic analysis combining with physiological measurement to illustrate the responsive mechanism of R. chrysanthum seedling under cold (4 degrees C) stress. After chilling for 12 h, 350 significantly changed proteins and 274 significantly changed phosphoproteins were detected. Clusters of Orthologous Groups (COG) analysis showed that significantly changed phosphoproteins and proteins indicated cold changed energy production and conversion and signal transduction. CONCLUSIONS: The results indicated photosynthesis was inhibited under cold stress, but cold induced calcium-mediated signaling, reactive oxygen species (ROS) homeostasis and other transcription regulation factors could protect plants from the destruction caused by cold stress. These data provide the insight to the cold stress response and defense mechanisms of R. chrysanthum leaves at the phosphoproteome level.
PMID: 34743272
Plant Signal Behav , IF:2.247 , 2021 Nov , V16 (11) : P1973711 doi: 10.1080/15592324.2021.1973711
Salicylic acid induces tolerance of VitisripariaxV.labrusca to chilling stress by altered photosynthetic, antioxidant mechanisms and expression of cold stress responsive genes.
College of Life Science and Technology,Gansu Agricultural University,Lanzhou,China.; Key Laboratory of Arid Land Crop Science of Gansu Province, College of Life Science and Technology,Gansu Agricultural University,Lanzhou,China.
The yield and quality of wine grapes are severely persecuted by low-temperaturestresses. Salicylic acid (SA) assists plants in coping with abiotic stresses such as drought, heavy metal toxicity, and osmotic stress. The objective of this study was to evaluate the effect of foliar spraying of different concentrations of SA on the mitigation of cold damage in grapes, which is useful for the cultivation of wine grapes.VitisripariaxV.labruscaseedlings were treated with foliar-sprayedSA at concentrations of 0-2 mM and then subjected to chilling stress at 4 degrees C for 2 or 4 days, while the expression of relevant physiological indicators and cold response genes (CBF1, CBF2, CBF3) were measured. The findings indicated that low temperature stresses markedly reduced chlorophyll content, and increased proline as well as soluble sugar content, enhanced superoxide dismutase (SOD) and peroxidase (POD) activities, decreased catalase (CAT) activity and inducedCBFgene expression in leaves. Physiologically, foliar spraying of different concentrations of SA greatly increased antioxidant enzyme activity (P < .05), soluble sugars, proline, and chlorophyll content of grapes leave under low temperature stress. With regard to gene expression, SA has significantly regulated the cold response genesCBF1, CBF2, andCBF3. Therefore, SA could reduce cold damage in grapevines under low-temperaturestress, and the effect of SA was most pronounced in the 1 and 2 mM concentrates.
PMID: 34523393