Trends Plant Sci , IF:18.313 , 2022 May , V27 (5) : P415-417 doi: 10.1016/j.tplants.2022.01.003
Post-translational activation of CBF for inducing freezing tolerance.
The Franciszek Gorski of Plant Physiology, Polish Academy of Sciences, Krakow 30-239, Poland. Electronic address: p.kopec@ifr-pan.edu.pl.; Department of Plant Breeding, Physiology and Seed Science, University of Agriculture, Krakow 31-120, Poland.; Department of Horticulture, Iowa State University, Ames, IA 50010, USA.
Plants can acquire increased freezing tolerance through cold-acclimation involving the ICE1-CBF-COR pathway. Recently, Lee et al. investigated a potential link between the functional activation of CBF and cellular redox state. We propose that redox-mediated CBF activation could be a hub of low temperature as well as light signaling in the cold-acclimation process.
PMID: 35090818
Plant Cell , IF:11.277 , 2022 May doi: 10.1093/plcell/koac137
Natural variation in the bZIP68 promoter modulates cold tolerance and was targeted during maize domestication.
State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing 100193, China.; State Key Laboratory of Plant Physiology and Biochemistry, National Maize Improvement Center, Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing 100193, China.
Maize (Zea mays) originated in tropical areas and is thus susceptible to low temperatures, which pose a major threat to maize production. Our understanding of the molecular basis of cold tolerance in maize is limited. Here, we identified bZIP68, a basic leucine zipper (bZIP) transcription factor, as a negative regulator of cold tolerance in maize. Transcriptome analysis revealed that bZIP68 represses the cold-induced expression of DREB1 transcription factor genes. The stability and transcriptional activity of bZIP68 are controlled by its phosphorylation at the conserved Ser250 residue under cold stress. Furthermore, we demonstrated that the bZIP68 locus was a target of selection during early domestication. A 358-bp insertion/deletion (Indel-972) polymorphism in the bZIP68 promoter has a significant effect on the differential expression of bZIP68 between maize and its wild ancestor teosinte. This study thus uncovered an evolutionary cis-regulatory variant that could be used to improve cold tolerance in maize.
PMID: 35543494
Plant Physiol , IF:8.34 , 2022 May doi: 10.1093/plphys/kiac208
Osa-miR1320 targets the ERF transcription factor OsERF096 to regulate cold tolerance via JA-mediated signaling.
Crop Stress Molecular Biology Laboratory, Heilongjiang Bayi Agricultural University, Daqing, 163319, China.; Key Laboratory of Germplasm Enhancement, Physiology and Ecology of Food Crops in Cold Region, Ministry of Education, Northeast Agricultural University, Harbin, 150030, China.
MicroRNAs play key roles in abiotic stress response. Rice (Oryza sativa L.) miR1320 is a species-specific miRNA that contributes to miR168-regulated immunity. However, it is still unknown whether miR1320 is involved in rice response to abiotic stress. In this study, we illustrated that the miR1320 precursor generated two mature miR1320s, miR1320-3p and miR1320-5p, and they both displayed decreased expression under cold stress. Genetic evidence showed that miR1320 overexpression resulted in increased cold tolerance, while miR1320 knockdown reduced cold tolerance. Furthermore, an AP2/ERF (APETALA2/ethylene-responsive factor) transcription factor OsERF096 was identified as a target of miR1320 via 5'-RACE and dual luciferase assays. OsERF096 expression was altered by miR1320 overexpression and knockdown and exhibited an opposite pattern to that of miR1320 in different tissues and under cold stress. Consistently, OsERF096 negatively regulated cold stress tolerance. Furthermore, we suggested that OsERF096 could bind to the GCC and DRE cis-elements and act as a transcriptional activator in the nucleus. Based on RNA-seq and targeted metabolomics assays, we found that OsERF096 modified hormone content and signaling pathways. Finally, phenotypic and RT-qPCR assays showed that MeJA application recovered the cold-sensitive phenotype and JA-activated expression of three DREB (Dehydration Responsive Element Binding) genes in the OsERF096-OE line. Taken together, our results strongly suggest that the miR1320-OsERF096 module regulates cold tolerance by repressing the JA-mediated cold signaling pathway.
PMID: 35522026
Plant Physiol , IF:8.34 , 2022 May doi: 10.1093/plphys/kiac211
The Transcription Factor MdMYB2 Influences Cold Tolerance and Anthocyanin Accumulation by Activating SUMO E3 Ligase MdSIZ1 in Apple.
State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China.; State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Landscaping, Ministry of Agriculture, College of Horticulture, Nanjing Agricultural University, Nanjing, China.; College of Food Science and Biological Engineering, Tianjin Agricultural University, Tianjin, 300384, China.
Conjugation of the small ubiquitin-like modifier (SUMO) peptide to target proteins is an important post-translational modification. SAP AND MIZ1 DOMAIN- CONTAINING LIGASE1 (MdSIZ1) is an apple (Malus domestica Borkh.) SUMO E3 ligase that mediates sumoylation of its targets during plant growth and development under adverse environmental conditions. However, it is unclear how MdSIZ1 senses the various environmental signals and whether sumoylation is regulated at the transcriptional level. In this study, we analyzed the MdSIZ1 promoter and found that it contained an MBS (MYB Binding Site) motif that was essential for the response of MdSIZ1 to low temperature and drought. Subsequently, we used yeast one-hybridization screening to demonstrate that a MYB transcription factor, MdMYB2, directly bound to the MBS motif in the MdSIZ1 promoter. Phenotypic characterization of MdMYB2 and MdSIZ1 suggested that the expression of both MdMYB2 and MdSIZ1 substantially improved cold tolerance in plants. MdMYB2 was induced by low temperature and further activated the expression of MdSIZ1, thereby promoting the sumoylation of MdMYB1, a key regulator of anthocyanin biosynthesis in apple. MdMYB2 promoted anthocyanin accumulation in apple fruits, apple calli, and Arabidopsis (Arabidopsis thaliana) in an MdSIZ1-dependent manner. In addition, the interaction of MdMYB2 and the MdSIZ1 promoter substantially improved plant tolerance to cold stress. Taken together, our findings reveal an important role for transcriptional regulation of sumoylation and provide insights into plant anthocyanin biosynthesis regulation mechanisms and stress response.
PMID: 35522008
J Exp Bot , IF:6.992 , 2022 May doi: 10.1093/jxb/erac195
Genetic basis and adaptive implications of temperature-dependent and temperature-independent effects of drought on chickpea reproductive phenology.
School of Agriculture, Food and Wine, The University of Adelaide.; South Australian Research and Development Institute, Australia.; Department of Agriculture and Fisheries, Kingaroy, Australia.
Water deficit often hastens flowering of pulses partially because droughted plants are hotter. Separating temperature-independent and temperature-dependent effects of drought is important to understand, model and manipulate phenology. We define a new trait, drought effect on phenology (DEP = difference in flowering time between irrigated and rainfed crops), and use FST genome scanning to probe for genomic regions under selection for this trait. Owing to the negligible variation in daylength, variation in phenology with sowing date was attributed to temperature and water; hence, genomic regions overlapping for early- and late-sown crops would associate with temperature-independent effects and non-overlapping genomic regions would associate with temperature-dependent effects. Thermal time to flowering was shortened with increasing water stress quantified with carbon isotope composition. Genomic regions on chromosomes 4, 5, 6, 7 and 8 were under selection for DEP. An overlapping region for early and late sowing on chromosome 8 revealed a temperature-independent effect with four candidate genes: BAM1, BAM2, HSL2 and ANT. The non-overlapping regions included six candidate genes: EMF1, EMF2, BRC1/TCP18, BZR1, NPGR1 and ERF1. Modelling showed DEP reduces the likelihood of drought and heat stress at the expense of cold stress. Accounting for DEP would improve genetic and phenotypic models of phenology.
PMID: 35526198
J Exp Bot , IF:6.992 , 2022 May , V73 (10) : P3138-3156 doi: 10.1093/jxb/erac045
Can we improve the chilling tolerance of maize photosynthesis through breeding?
Department of Plant Sciences, University of Cambridge Cambridge, UK.
Chilling tolerance is necessary for crops to thrive in temperate regions where cold snaps and lower baseline temperatures place limits on life processes; this is particularly true for crops of tropical origin such as maize. Photosynthesis is often adversely affected by chilling stress, yet the maintenance of photosynthesis is essential for healthy growth and development, and most crucially for yield. In this review, we describe the physiological basis for enhancing chilling tolerance of photosynthesis in maize by examining nine key responses to chilling stress. We synthesize current knowledge of genetic variation for photosynthetic chilling tolerance in maize with respect to each of these traits and summarize the extent to which genetic mapping and candidate genes have been used to understand the genomic regions underpinning chilling tolerance. Finally, we provide perspectives on the future of breeding for photosynthetic chilling tolerance in maize. We advocate for holistic and high-throughput approaches to screen for chilling tolerance of photosynthesis in research and breeding programmes in order to develop resilient crops for the future.
PMID: 35143635
J Exp Bot , IF:6.992 , 2022 Apr , V73 (7) : P2222-2237 doi: 10.1093/jxb/erab555
Genome-wide association study identifies variants of GhSAD1 conferring cold tolerance in cotton.
State Key Laboratory of Cotton Biology, Institute of Cotton Research of CAAS, Anyang, China.; Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China.
Cold stress is a major environmental factor affecting plant growth and development. Although some plants have developed resistance to cold stress, the molecular mechanisms underlying this process are poorly understood. Using genome-wide association mapping with 200 cotton accessions collected from different regions, we identified variations in the short chain alcohol dehydrogenase gene, GhSAD1, that responds to cold stress. Virus-induced gene silencing and overexpression in Arabidopsis revealed that GhSAD1 fulfils important roles in cold stress responses. Ectopic expression of a haploid genotype of GhSAD1 (GhSAD1HapB) in Arabidopsis increased cold tolerance. Silencing of GhSAD1HapB resulted in a decrease in abscisic acid (ABA) content. Conversely, overexpression of GhSAD1HapB increased ABA content. GhSAD1HapB regulates cold stress responses in cotton through modulation of C-repeat binding factor activity, which regulates ABA signalling. GhSAD1HapB induces the expression of COLD-REGULATED (COR) genes and increases the amount of metabolites associated with cold stress tolerance. Overexpression of GhSAD1HapB partially complements the phenotype of the Arabidopsis ABA2 mutant, aba2-1. Collectively, these findings increase our understanding of the mechanisms underlying GhSAD1-mediated cold stress responses in cotton.
PMID: 34919655
J Exp Bot , IF:6.992 , 2022 Apr , V73 (8) : P2666-2681 doi: 10.1093/jxb/erac029
Overexpression mutants reveal a role for a chloroplast MPD protein in regulation of reactive oxygen species during chilling in Arabidopsis.
Institute of Biological Chemistry, Washington State University, Pullman, WA 99164-6340, USA.
Reactive oxygen species (ROS) contribute to cellular damage in several different contexts, but their role during chilling damage is poorly defined. Chilling sensitivity both limits the distribution of plant species and causes devastating crop losses worldwide. Our screen of chilling-tolerant Arabidopsis (Arabidopsis thaliana) for mutants that suffer chilling damage identified a gene (At4g03410) encoding a chloroplast Mpv17_PMP22 protein, MPD1, with no previous connection to chilling. The chilling-sensitive mpd1-1 mutant is an overexpression allele that we successfully phenocopied by creating transgenic lines with a similar level of MPD1 overexpression. In mammals and yeast, MPD1 homologs are associated with ROS management. In chilling conditions, Arabidopsis overexpressing MPD1 accumulated H2O2 to higher levels than wild-type controls and exhibited stronger induction of ROS response genes. Paraquat application exacerbated chilling damage, confirming that the phenotype occurs due to ROS dysregulation. We conclude that at low temperature increased MPD1 expression results in increased ROS production, causing chilling damage. Our discovery of the effect of MPD1 overexpression on ROS production under chilling stress implies that investigation of the nine other members of the Mpv17_PMP22 family in Arabidopsis may lead to new discoveries regarding ROS signaling and management in plants.
PMID: 35084440
Cells , IF:6.6 , 2022 Apr , V11 (7) doi: 10.3390/cells11071240
Total and Mitochondrial Transcriptomic and Proteomic Insights into Regulation of Bioenergetic Processes for Shoot Fast-Growth Initiation in Moso Bamboo.
National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China.; College of Agriculture and Forestry Engineering and Planning, Tongren University, Tongren 554300, China.; International Center for Bamboo and Rattan, Key Laboratory of Bamboo and Rattan Science and Technology, State Forestry and Grassland Administration, Beijing 100102, China.
As a fast-growing, woody grass plant, Moso bamboo (Phyllostachys edulis) can supply edible shoots, building materials, fibrous raw material, raw materials for crafts and furniture and so on within a relatively short time. Rapid growth of Moso bamboo occurs after the young bamboo shoots are covered with a shell and emerge from the ground. However, the molecular reactions of bioenergetic processes essential for fast growth remain undefined. Herein, total and mitochondrial transcriptomes and proteomes were compared between spring and winter shoots. Numerous key genes and proteins responsible for energy metabolism were significantly upregulated in spring shoots, including those involved in starch and sucrose catabolism, glycolysis, the pentose phosphate pathway, the tricarboxylic acid cycle and oxidative phosphorylation. Accordingly, significant decreases in starch and soluble sugar, higher ATP content and higher rates of respiration and glycolysis were identified in spring shoots. Further, the upregulated genes and proteins related to mitochondrial fission significantly increased the number of mitochondria, indirectly promoting intracellular energy metabolism. Moreover, enhanced alternate-oxidase and uncoupled-protein pathways in winter shoots showed that an efficient energy-dissipating system was important for winter shoots to adapt to the low-temperature environment. Heterologous expression of PeAOX1b in Arabidopsis significantly affected seedling growth and enhanced cold-stress tolerance. Overall, this study highlights the power of comparing total and mitochondrial omics and integrating physiochemical data to understand how bamboo initiates fast growth through modulating bioenergetic processes.
PMID: 35406802
Cells , IF:6.6 , 2022 Apr , V11 (8) doi: 10.3390/cells11081321
Comparative Proteomics Combined with Morphophysiological Analysis Revealed Chilling Response Patterns in Two Contrasting Maize Genotypes.
College of Agriculture, Northeast Agricultural University, Harbin 150030, China.; Jilin Province Engineering Laboratory of Plant Genetic Improvement, College of Plant Science, Jilin University, Changchun 130062, China.; Basic Forestry and Proteomics Research Center, Fujian Agriculture and Forestry University, Fuzhou 350002, China.; Institute of Maize Research, Heilongjiang Academy of Agricultural Sciences, Harbin 150030, China.
Maize yield is significantly influenced by low temperature, particularly chilling stress at the maize seedling stage. Various physiological approaches have been established to resist chilling stress; however, the detailed proteins change patterns underlying the maize chilling stress response at the seedling stage remain unknown, preventing the development of breeding-based methods to resist chilling stress in maize. Thus, we performed comprehensive physiological, comparative proteomics and specific phytohormone abscisic acid (ABA) assay on different maize inbred lines (tolerant-line KR701 and sensitive-line hei8834) at different seedling stages (the first leaf stage and third leaf stage) under chilling stress. The results revealed several signalling proteins and pathways in response to chilling stress at the maize seedling stage. Meanwhile, we found ABA pathway was important for chilling resistance of tolerant-line KR701 at the first leaf stage. Related chilling-responsive proteins were further catalogued and analysed, providing a resource for further investigation and maize breeding.
PMID: 35456000
Plant J , IF:6.417 , 2022 May doi: 10.1111/tpj.15807
The miR164a-NAM3 module confers cold tolerance by inducing ethylene production in tomato.
Department of Horticulture, Zijingang Campus, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, P.R. China.; Key Laboratory of Horticultural Plants Growth and Development, Agricultural Ministry of China, Yuhangtang Road 866, Hangzhou, 310058, P.R. China.
Due to the high sensitivity to cold, the yield and quality of tomato (Solanum lycopersicum L.) are severely restricted by cold stress. The NAC transcription factor (TF) family has been characterized as an important player in plant growth, development, and stress response, but the role of NAC TFs in cold stress and their interaction with other post-transcriptional regulators such as microRNAs in cold tolerance remain elusive. Here, we demonstrated that SlNAM3, the predicted target of Sl-miR164a/b-5p, improved cold tolerance as evidenced by a higher maximum quantum efficiency of photosystem II (Fv/Fm), lower relative electrolyte leakage (REL) and less wilting in SlNAM3-overexpression plants than wild-type. Further genetic and molecular confirmation revealed that Sl-miR164a/b-5p functioned upstream of SlNAM3 by inhibiting the expression of the latter, thus playing a negative role in cold tolerance. Interestingly, this role is partially mediated by an ethylene-dependent pathway, as either Sl-miR164a/b-5p silencing or SlNAM3 overexpression improved cold tolerance in the transgenic lines by promoting ethylene production. Moreover, silencing the ethylene synthesis genes, SlACS1A, SlACS1B, SlACO1, and SlACO4, resulted in a significant decrease in cold tolerance. Further experiments demonstrated that NAM3 activates SlACS1A, SlACS1B, SlACO1, and SlACO4 transcription by directly binding to their promoters. Taken together, our study identified the miR164a-NAM3 module conferring cold tolerance in tomato plants via the direct regulation of SlACS1A, SlACS1B, SlACO1, and SlACO4 expression to induce ethylene synthesis.
PMID: 35569132
Plant J , IF:6.417 , 2022 Apr doi: 10.1111/tpj.15780
Heat shock-induced cold acclimation in cucumber through CsHSFA1d-activated JA biosynthesis and signaling.
College of Horticulture, China Agricultural University, Beijing, 100193, China.; Institute of Economic Crops, Hubei Academy of Agricultural Sciences, Wuhan, Hubei Province, 430064, China.; Shandong Huasheng Agriculture Co. Ltd, Qingzhou, Shandong, 262500, China.; School of Agriculture, Virginia State University, Petersburg, VA, USA.
Cucumber (Cucumis sativus) originated in tropical areas and is very sensitive to low temperatures. Cold acclimation is a universal strategy that improves plant resistance to cold stress. In this study, we report that heat shock induces cold acclimation in cucumber seedlings, via a process involving the heat-shock transcription factor HSFA1d. CsHSFA1d expression was improved by both heat shock and cold treatment. Moreover, CsHSFA1d transcripts accumulated more under cold treatment after a heat-shock pre-treatment than with either heat shock or cold treatment alone. After exposure to cold, cucumber lines overexpressing CsHSFA1d displayed stronger tolerance for cold stress than the wild type, whereas CsHSFA1d knockdown lines obtained by RNA interference were more sensitive to cold stress. Furthermore, both the overexpression of CsHSFA1d and heat-shock pre-treatment increased the endogenous jasmonic acid (JA) content in cucumber seedlings after cold treatment. Exogenous application of JA rescued the cold-sensitive phenotype of CsHSFA1d knockdown lines, underscoring that JA biosynthesis is key for CsHSFA1d-mediated cold tolerance. Higher JA content is likely to lead to the degradation of CsJAZ5, a repressor protein of the JA pathway. We also established that CsJAZ5 interacts with CsICE1. JA-induced degradation of CsJAZ5 would be expected to release CsICE1, which would then activate the ICE-CBF-COR pathway. After cold treatment, the relative expression levels of ICE-CBF-COR signaling pathway genes, such as CsICE1, CsCBF1, CsCBF2 and CsCOR1, in CsHSFA1d overexpression lines were significantly higher than in the wild type and knockdown lines. Taken together, our results help to reveal the mechanism underlying heat shock-induced cold acclimation in cucumber.
PMID: 35436390
Antioxidants (Basel) , IF:6.312 , 2022 May , V11 (5) doi: 10.3390/antiox11050969
Photosynthesis Mediated by RBOH-Dependent Signaling Is Essential for Cold Stress Memory.
Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China.; Engineering Research Center of the Ministry of Education for Horticultural Crops Breeding and Propagation, College of Horticulture, China Agricultural University, Beijing 100193, China.; Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China.; College of Life Science, Gannan Normal University, Ganzhou 341000, China.
Cold tolerance is improved by cold stress acclimation (CS-ACC), and the cold tolerance level is 'remembered' by plants. However, the underlying signaling mechanisms remain largely unknown. Here, the CS memory mechanism was studied by bioinformation, plant physiological and photosynthetic parameters, and gene expression. We found that CS-ACC induced the acquisition of CS memory and enhanced the maintenance of acquired cold tolerance (MACT) in cucumber seedlings. The H2O2 content and NADPH oxidase activity encoded by CsRBOH was maintained at higher levels during recovery after CS-ACC and inhibition of RBOH-dependent signaling after CS-ACC resulted in a decrease in the H2O2 content, NADPH oxidase activity, and MACT. CsRBOH2, 3, 4, and 5 showed high expression during recovery after CS-ACC. Many BZR-binding sites were identified in memory-responsive CsRBOHs promoters, and CsBZR1 and 3 showed high expression during recovery after CS-ACC. Inhibition of RBOH-dependent signaling or brassinosteroids affected the maintenance of the expression of these memory-responsive CsRBOHs and CsBZRs. The photosynthetic efficiency (PE) decreased but then increased with the prolonged recovery after CS-ACC, and was higher than the control at 48 h of recovery; however, inhibition of RBOH-dependent signaling resulted in a lower PE. Further etiolated seedlings experiments showed that a photosynthetic capacity was necessary for CS memory. Therefore, photosynthesis mediated by RBOH-dependent signaling is essential for CS memory.
PMID: 35624833
Antioxidants (Basel) , IF:6.312 , 2022 May , V11 (5) doi: 10.3390/antiox11050977
Integrative Comparative Assessment of Cold Acclimation in Evergreen and Deciduous Iris Species.
Genomics and Genetic Engineering Laboratory of Ornamental Plants, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China.
Cold acclimation (CA) is a strategy which plants have evolved to increase freezing tolerance. Global climate change could obstruct CA and raise the probability of winter injury, especially for evergreens. Hence, understanding the regulatory mechanism of CA is crucial to improve freezing tolerance in evergreen plants. A comparative study on a pair of closely related evergreen and deciduous iris species in response to cold through CA was conducive to uncovering and complementing the knowledge of CA. We investigated morphological, physiological and biochemical changes, as well as the expression of associated genes in the functional leaves of both iris species from natural CA to deacclimation. Briefly, fast and strong CA in the evergreen iris might cause early expressions of BAM1, NCED3, GPX6, etc., which leads to strong enzyme activity of starch degradation, abscisic acid biosynthesis and reactive oxygen species scavenging. Additionally, genes belonging to the antioxidant system were mainly induced during deacclimation. These results suggest that interspecies differences in the leaf freezing tolerance of irises are associated with the rate and degree of CA, which activates multiple signaling networks with complex interactions and induces the transcription of cold-responsive genes. Moreover, the ICE-CBF-COR signaling cascade may integrate and initiate diverse cold-responsive pathways during CA of the evergreen iris. The findings of this study provide valuable insight to further research on CA mechanisms and implicate genes which could support breeding strategies in herbaceous perennials under climate changes.
PMID: 35624841
Int J Mol Sci , IF:5.923 , 2022 May , V23 (10) doi: 10.3390/ijms23105724
Full-Length Transcriptome Sequencing Reveals the Impact of Cold Stress on Alternative Splicing in Quinoa.
Shandong Provincial Key Laboratory of Plant Stress, Life Science College, Shandong Normal University, Jinan 250014, China.; CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China.
Quinoa is a cold-resistant and nutrient-rich crop. To decipher the cold stress response of quinoa, the full-length transcriptomes of the cold-resistant quinoa variety CRQ64 and the cold-sensitive quinoa variety CSQ5 were compared. We identified 55,389 novel isoforms and 6432 novel genes in these transcriptomes. Under cold stress, CRQ64 had more differentially expressed genes (DEGs) and differentially alternative splicing events compared to non-stress conditions than CSQ5. DEGs that were specifically present only in CRQ64 were significantly enriched in processes which contribute to osmoregulation and ROS homeostasis in plants, such as sucrose metabolism and phenylpropanoid biosynthesis. More genes with differential alternative splicing under cold stress were enriched in peroxidase functions in CRQ64. In total, 5988 transcription factors and 2956 long non-coding RNAs (LncRNAs) were detected in this dataset. Many of these had altered expression patterns under cold stress compared to non-stress conditions. Our transcriptome results demonstrate that CRQ64 undergoes a wider stress response than CSQ5 under cold stress. Our results improved the annotation of the quinoa genome and provide new insight into the mechanisms of cold resistance in quinoa.
PMID: 35628539
Int J Mol Sci , IF:5.923 , 2022 May , V23 (10) doi: 10.3390/ijms23105615
Unveiling Molecular Mechanisms of Nitric Oxide-Induced Low-Temperature Tolerance in Cucumber by Transcriptome Profiling.
Key Laboratory of Special Fruits and Vegetables Cultivation Physiology and Germplasm Resources Utilization of Xinjiang Production and Construction Group, College of Agriculture, Shihezi University, Shihezi 832000, China.; College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China.; College of Horticulture and Plant Protection, Henan University of Science and Technology, Luoyang 471023, China.
Cucumber (Cucumis sativus L.) is one of the most popular cultivated vegetable crops but it is intrinsically sensitive to cold stress due to its thermophilic nature. To explore the molecular mechanism of plant response to low temperature (LT) and the mitigation effect of exogenous nitric oxide (NO) on LT stress in cucumber, transcriptome changes in cucumber leaves were compared. The results showed that LT stress regulated the transcript level of genes related to the cell cycle, photosynthesis, flavonoid accumulation, lignin synthesis, active gibberellin (GA), phenylalanine metabolism, phytohormone ethylene and salicylic acid (SA) signaling in cucumber seedlings. Exogenous NO improved the LT tolerance of cucumber as reflected by increased maximum photochemical efficiency (Fv/Fm) and decreased chilling damage index (CI), electrolyte leakage and malondialdehyde (MDA) content, and altered transcript levels of genes related to phenylalanine metabolism, lignin synthesis, plant hormone (SA and ethylene) signal transduction, and cell cycle. In addition, we found four differentially expressed transcription factors (MYB63, WRKY21, HD-ZIP, and b-ZIP) and their target genes such as the light-harvesting complex I chlorophyll a/b binding protein 1 gene (LHCA1), light-harvesting complex II chlorophyll a/b binding protein 1, 3, and 5 genes (LHCB1, LHCB3, and LHCB5), chalcone synthase gene (CSH), ethylene-insensitive protein 3 gene (EIN3), peroxidase, phenylalanine ammonia-lyase gene (PAL), DNA replication licensing factor gene (MCM5 and MCM6), gibberellin 3 beta-dioxygenase gene (GA3ox), and regulatory protein gene (NPRI), which are potentially associated with plant responses to NO and LT stress. Notably, HD-ZIP and b-ZIP specifically responded to exogenous NO under LT stress. Taken together, these results demonstrate that cucumber seedlings respond to LT stress and exogenous NO by modulating the transcription of some key transcription factors and their downstream genes, thereby regulating photosynthesis, lignin synthesis, plant hormone signal transduction, phenylalanine metabolism, cell cycle, and GA synthesis. Our study unveiled potential molecular mechanisms of plant response to LT stress and indicated the possibility of NO application in cucumber production under LT stress, particularly in winter and early spring.
PMID: 35628425
Int J Mol Sci , IF:5.923 , 2022 Apr , V23 (9) doi: 10.3390/ijms23094846
Molecular Cloning and Characterization of MbMYB108, a Malus baccata MYB Transcription Factor Gene, with Functions in Tolerance to Cold and Drought Stress in Transgenic Arabidopsis thaliana.
Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northeast Region), Ministry of Agriculture and Rural Affairs/National-Local Joint Engineering Research Center for Development and Utilization of Small Fruits in Cold Regions/College of Horticulture & Landscape Architecture, Northeast Agricultural University, Harbin 150030, China.; Horticulture Branch of Heilongjiang Academy of Agricultural Sciences, Harbin 150040, China.
The MYB transcription factor (TF) family is one of the largest transcription families in plants, which is widely involved in the responses of plants to biotic and abiotic stresses, as well as plant growth, development, and metabolic regulation. In the present study, a new MYB TF gene, MbMYB108, from Malus baccata (L.) Borkh, was identified and characterized. The open reading frame (ORF) of MbMYB108 was found to be 903 bp, encoding 300 amino acids. Sequence alignment results and predictions of the protein structure indicated that the MbMYB108 protein contained the conserved MYB domain. Subcellular localization showed that MbMYB108 was localized to the nucleus. The expression of MbMYB108 was enriched in young and mature leaves, and was highly affected by cold and drought treatments in M. baccata seedlings. When MbMYB108 was introduced into Arabidopsis thaliana, it greatly increased the cold and drought tolerances in the transgenic plant. Increased expression of MbMYB108 in transgenic A. thaliana also resulted in higher activities of peroxidase (POD) and catalase (CAT), higher contents of proline and chlorophyll, while malondialdehyde (MDA) content and relative conductivity were lower, especially in response to cold and drought stresses. Therefore, these results suggest that MbMYB108 probably plays an important role in the response to cold and drought stresses in A. thaliana by enhancing the scavenging capability for reactive oxygen species (ROS).
PMID: 35563237
Int J Mol Sci , IF:5.923 , 2022 Apr , V23 (9) doi: 10.3390/ijms23094522
Genome-Wide Identification, Classification and Expression Analysis of m(6)A Gene Family in Solanum lycopersicum.
Laboratory of Molecular Biology of Tomato, Bioengineering College, Chongqing University, Chongqing 400030, China.
Advanced knowledge of messenger RNA (mRNA) N(6)-methyladenosine (m(6)A) and DNA N(6)-methyldeoxyadenosine (6 mA) redefine our understanding of these epigenetic modifications. Both m(6)A and 6mA carry important information for gene regulation, and the corresponding catalytic enzymes sometimes belong to the same gene family and need to be distinguished. However, a comprehensive analysis of the m(6)A gene family in tomato remains obscure. Here, 24 putative m(6)A genes and their family genes in tomato were identified and renamed according to BLASTP and phylogenetic analysis. Chromosomal location, synteny, phylogenetic, and structural analyses were performed, unravelling distinct evolutionary relationships between the MT-A70, ALKBH, and YTH protein families, respectively. Most of the 24 genes had extensive tissue expression, and 9 genes could be clustered in a similar expression trend. Besides, SlYTH1 and SlYTH3A showed a different expression pattern in leaf and fruit development. Additionally, qPCR data revealed the expression variation under multiple abiotic stresses, and LC-MS/MS determination exhibited that the cold stress decreased the level of N(6) 2'-O dimethyladenosine (m(6)Am). Notably, the orthologs of newly identified single-strand DNA (ssDNA) 6mA writer-eraser-reader also existed in the tomato genome. Our study provides comprehensive information on m(6)A components and their family proteins in tomato and will facilitate further functional analysis of the tomato N(6)-methyladenosine modification genes.
PMID: 35562913
Front Plant Sci , IF:5.753 , 2022 , V13 : P852511 doi: 10.3389/fpls.2022.852511
Analysis of the Expression and Function of Key Genes in Pepper Under Low-Temperature Stress.
College of Horticulture, Hunan Agricultural University, Changsha, China.; Longping Branch, Graduate School of Hunan University, Changsha, China.; ERC for Germplasm Innovation and New Variety, Breeding of Horticultural Crops, Changsha, China.; Key Laboratory for Vegetable Biology of Hunan Province, Changsha, China.
The mechanism of resistance of plants to cold temperatures is very complicated, and the molecular mechanism and related gene network in pepper are largely unknown. Here, during cold treatment, we used cluster analysis (k-means) to classify all expressed genes into 15 clusters, 3,680 and 2,405 differentially expressed genes (DEGs) were observed in the leaf and root, respectively. The DEGs associated with certain important basic metabolic processes, oxidoreductase activity, and overall membrane compositions were most significantly enriched. In addition, based on the homologous sequence alignment of Arabidopsis genes, we identified 14 positive and negative regulators of the ICE-CBF-COR module in pepper, including CBF and ICE, and compared their levels in different data sets. The correlation matrix constructed based on the expression patterns of whole pepper genes in leaves and roots after exposure to cold stress showed the correlation between 14 ICE-CBF-COR signaling module genes, and provided insight into the relationship between these genes in pepper. These findings not only provide valuable resources for research on cold tolerance, but also lay the foundation for the genetic modification of cold stress regulators, which would help us achieve improved crop tolerance. To our knowledge, this is the first study to demonstrate the relationship between positive and negative regulators related to the ICE-CBF-COR module, which is of great significance to the study of low-temperature adaptive mechanisms in plants.
PMID: 35599873
Front Plant Sci , IF:5.753 , 2022 , V13 : P867503 doi: 10.3389/fpls.2022.867503
Genome-Wide Identification of Wild Soybean Mitochondrial Calcium Uniporter Family Genes and Their Responses to Cold and Carbonate Alkaline Stresses.
Crop Stress Molecular Biology Laboratory, College of Agriculture, Heilongjiang Bayi Agricultural University, Daqing, China.; Key Laboratory of Soybean Biology of Chinese Education Ministry, Northeast Agricultural University, Harbin, China.
The mitochondrial calcium uniporter (MCU), as an important component of the Ca(2+) channel uniporter complex, plays a regulatory role in intracellular Ca(2+) signal transduction. However, only a few studies to date have investigated plant MCU genes. In this study, we identified the MCU family genes in wild soybean and investigated their expression under cold and carbonate alkaline stresses. Eleven Glycine soja MCU genes (GsMCUs) were identified and clustered into two subgroups (subgroups I and II), and subgroup II could be further divided into two branches (MCU5 and MCU6). A total of 21 pairs of GsMCUs were characterized as duplicated genes, and displayed a similar exon-intron architecture. All GsMCU proteins contained one conserved MCU domain, within which two transmembrane domains were found. An analysis of the conserved motifs further supported that the GsMCUs showed high conservation in protein sequence and structure. Moreover, we found that all GsMCUs were expressed ubiquitously in different tissues and organs, and GsMCUs from the same subgroup displayed varied tissue expression profiles. In addition, based on RNA-seq and qRT-PCR assays, six and nine GsMCUs were differentially expressed under cold and carbonate alkaline stress, respectively. Promoter analysis also uncovered the existence of two canonical cold-related cis-acting elements, LTR and DRE/CRT, as well as stress-related phytohormone-responsive elements. Our results provide valuable information about the MCU family in soybean responses to cold and carbonate alkaline stress, which will be helpful in further characterizing their biological roles in response to abiotic stress.
PMID: 35592573
Front Plant Sci , IF:5.753 , 2022 , V13 : P886525 doi: 10.3389/fpls.2022.886525
Physiological, Structural, and Functional Insights Into the Cryoprotection of Membranes by the Dehydrins.
Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada.; Graduate Program in Bioinformatics, University of Guelph, Guelph, ON, Canada.
Plants can be exposed to cold temperatures and have therefore evolved several mechanisms to prevent damage caused by freezing. One of the most important targets are membranes, which are particularly susceptible to cold damage. To protect against such abiotic stresses, plants express a family of proteins known as late embryogenesis abundant (LEA) proteins. Many LEA proteins are intrinsically disordered, that is, they do not contain stable secondary or tertiary structures alone in solution. These proteins have been shown in a number of studies to protect plants from damage caused by cold, drought, salinity, and osmotic stress. In this family, the most studied proteins are the type II LEA proteins, better known as dehydrins (dehydration-induced proteins). Many physiological studies have shown that dehydrins are often located near the membrane during abiotic stress and that the expression of dehydrins helps to prevent the formation of oxidation-modified lipids and reduce the amount of electrolyte leakage, two hallmarks of damaged membranes. One of the earliest biophysical clues that dehydrins are involved in membrane cryoprotection came from in vitro studies that demonstrated a binding interaction between the protein and membranes. Subsequent work has shown that one conserved motif, known as K-segments, is involved in binding, while recent studies have used NMR to explore the residue specific structure of dehydrins when bound to membranes. The biophysical techniques also provide insight into the mechanism by which dehydrins protect the membrane from cold stress, which appears to mainly involve the lowering of the transition temperature.
PMID: 35574140
Front Plant Sci , IF:5.753 , 2022 , V13 : P847202 doi: 10.3389/fpls.2022.847202
Plant Hormone Response to Low-Temperature Stress in Cold-Tolerant and Cold-Sensitive Varieties of Zanthoxylum bungeanum Maxim.
College of Forestry, Northwest A&F University, Xianyang, China.; School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China.
Plant growth and survival in nature, its growth process, will be affected by various factors from the environment, among which temperature has a greater impact. In recent years, extreme weather has frequently appeared, and the growth of crops has been increasingly affected by the environment. As an important flavoring and Chinese herbal medicine crop, Zanthoxylum bungeanum is also facing the harm of low-temperature stress. Plant hormones play a vital role in the response of plants to low temperatures. In this study, ultra-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to determine the hormone components of cold-tolerant and cold-sensitive varieties of Z. bungeanum. Combined with chemometric analysis and weighted gene co-expression network analysis (WGCNA), the hormone component differences and hormone response strategies of Z. bungeanum under low-temperature stress were comprehensively studied. The results showed that 45 hormones were detected in Z. bungeanum. Among them, there were 7 kinds of components with high content and were detected in both two varieties. At the late stage of low-temperature stress, the contents of abscisic acid (ABA) and ABA-glucosyl ester (ABA-GE) in Fuguhuajiao (FG) were significantly increased, and the latter served as the storage of the former to supplement the active ABA. Orthogonal partial least squares discriminant analysis (OPLS-DA) found that indole-3-carboxylic acid (ICA), indole-3-carboxaldehyde (ICAld), meta-Topolin riboside (mTR), cis-Zeatin-O-glucoside riboside (cZROG), and N6-isopentenyladenosine (IPR) in FG were the upregulated important difference components, and IPR and 2-methylthio-cis-zeatin riboside (2MeScZR) in Fengxiandahongpao (FX) were the upregulated important difference components. There were common crossing points and independent response pathways in response to low temperature in two varieties. WGCNA analysis found that the main hormone components were associated with multiple metabolic pathways including carbon, fatty acid, amino acid, and sugar metabolism, indicating that hormone regulation plays an important role in the response of Z. bungeanum to low temperature. This study clarified the hormone response mechanism of Z. bungeanum under low-temperature stress and provided a reference and basis for further improving the cold resistance of Z. bungeanum and cultivating new varieties.
PMID: 35574137
Front Plant Sci , IF:5.753 , 2022 , V13 : P855559 doi: 10.3389/fpls.2022.855559
Calcium Mediated Cold Acclimation in Plants: Underlying Signaling and Molecular Mechanisms.
Molecular Crop Research Unit, Department of Biochemistry, Chulalongkorn University, Bangkok, Thailand.; Department of Biochemistry, College of Medicine, Qassim University, Buraydah, Saudi Arabia.; Amity Institute of Biotechnology, Amity University Lucknow, Lucknow, India.
Exposure of plants to low temperatures adversely affects plant growth, development, and productivity. Plant response to cold stress is an intricate process that involves the orchestration of various physiological, signaling, biochemical, and molecular pathways. Calcium (Ca(2+)) signaling plays a crucial role in the acquisition of several stress responses, including cold. Upon perception of cold stress, Ca(2+) channels and/or Ca(2+) pumps are activated, which induces the Ca(2+) signatures in plant cells. The Ca(2+) signatures spatially and temporally act inside a plant cell and are eventually decoded by specific Ca(2+) sensors. This series of events results in the molecular regulation of several transcription factors (TFs), leading to downstream gene expression and withdrawal of an appropriate response by the plant. In this context, calmodulin binding transcription activators (CAMTAs) constitute a group of TFs that regulate plant cold stress responses in a Ca(2+) dependent manner. The present review provides a catalog of the recent progress made in comprehending the Ca(2+) mediated cold acclimation in plants.
PMID: 35574126
Front Plant Sci , IF:5.753 , 2022 , V13 : P860945 doi: 10.3389/fpls.2022.860945
AtRsmD Is Required for Chloroplast Development and Chloroplast Function in Arabidopsis thaliana.
Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai, China.
AtRsmD was recently demonstrated to be a chloroplast 16S rRNA methyltransferase (MTase) for the m(2)G915 modification in Arabidopsis. Here, its function of AtRsmD for chloroplast development and photosynthesis was further analyzed. The AtRsmD gene is highly expressed in green photosynthetic tissues. AtRsmD is associated with the thylakoid in chloroplasts. The atrsmd-2 mutant exhibited impaired photosynthetic efficiency in emerging leaves under normal growth conditions. A few thylakoid lamellas could be observed in the chloroplast from the atrsmd-2 mutant, and these thylakoids were loosely organized. Knockout of the AtRsmD gene had minor effects on chloroplast ribosome biogenesis and RNA loading on chloroplast ribosomes, but it reduced the amounts of chloroplast-encoded photosynthesis-related proteins in the emerging leaves, for example, D1, D2, CP43, and CP47, which reduced the accumulation of the photosynthetic complex. Nevertheless, knockout of the AtRsmD gene did not cause a general reduction in chloroplast-encoded proteins in Arabidopsis grown under normal growth conditions. Additionally, the atrsmd-2 mutant exhibited more sensitivity to lincomycin, which specifically inhibits the elongation of nascent polypeptide chains. Cold stress exacerbated the effect on chloroplast ribosome biogenesis in the atrsmd-2 mutant. All these data suggest that the AtRsmD protein plays distinct regulatory roles in chloroplast translation, which is required for chloroplast development and chloroplast function.
PMID: 35548310
Front Plant Sci , IF:5.753 , 2022 , V13 : P866034 doi: 10.3389/fpls.2022.866034
Recent Advances in the Analysis of Cold Tolerance in Maize.
Maize Research Institute, Sichuan Agricultural University, Chengdu, China.; Department of Chemistry, Punjab College of Science, Faisalabad, Pakistan.; State Key Laboratory of Crop Gene Resource Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, China.
Maize (Zea mays L.) is an annual grass that originated in tropical and subtropical regions of the New World. Maize is highly sensitive to cold stress during seed gemination and the seedling phase, which can lead to reductions in plant vigor and grain production. There are large differences in the morphological and physiological changes caused by cold stress among maize varieties. In general, cold tolerant varieties have a stronger ability to maintain such changes in traits related to seed germination, root phenotypes, and shoot photosynthesis. These morphological and physiological characteristics have been widely used to evaluate the cold tolerance of maize varieties in genetic analyses. In recent years, considerable progress has been made in elucidating the mechanisms of maize in response to cold tolerance. Several QTL, GWAS, and transcriptomic analyses have been conducted on various maize genotypes and populations that show large variations in cold tolerance, resulting in the discovery of hundreds of candidate cold regulation genes. Nevertheless, only a few candidate genes have been functionally characterized. In the present review, we summarize recent progress in molecular, physiological, genetic, and genomic analyses of cold tolerance in maize. We address the advantages of joint analyses that combine multiple genetic and genomic approaches to improve the accuracy of identifying cold regulated genes that can be further used in molecular breeding. We also discuss the involvement of long-distance signaling in plant cold tolerance. These novel insights will provide a better mechanistic understanding of cold tolerance in maize.
PMID: 35498657
Front Plant Sci , IF:5.753 , 2022 , V13 : P831314 doi: 10.3389/fpls.2022.831314
Cold Stress Resistance of Tomato (Solanum lycopersicum) Seedlings Is Enhanced by Light Supplementation From Underneath the Canopy.
Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China.; College of Horticulture, Xinjiang Agricultural University, Urumqi, China.; Natural Resources Bureau of Hutubi County in Xinjiang Province, Changji, China.; Taizhou Academy of Agricultural Sciences, Taizhou, China.; Agriculture and Animal Husbandry Comprehensive Inspection and Testing Center of Chifeng, Chifeng, China.; Tibet Academy of Agriculture and Animal Husbandry Sciences Vegetable Research Institute, Lhasa, China.
Adverse environmental conditions, such as low temperature (LT), greatly limit the growth and production of tomato. Recently, light-emitting diodes (LEDs) with specific spectra have been increasingly used in horticultural production facilities. The chosen spectrum can affect plant growth, development, and resistance, but the physiological regulatory mechanisms are largely unknown. In this study, we investigated the effects of LED light supplementation (W:B = 2:1, light intensity of 100 mumolm(-2)s(-1), for 4 h/day from 9:00 to 13:00) from above and below the canopy on tomato resistance under sub-LT stress (15/8 degrees C). The results showed that supplemental lighting from underneath the canopy (USL) promoted the growth of tomato seedlings, as the plant height, stem diameter, root activity, and plant biomass were significantly higher than those under LT. The activity of the photochemical reaction center was enhanced because of the increase in the maximal photochemical efficiency (F v /F m ) and photochemical quenching (qP), which distributed more photosynthetic energy to the photochemical reactions and promoted photosynthetic performance [the maximum net photosynthetic rate (Pmax) was improved]. USL also advanced the degree of stomatal opening, thus facilitating carbon assimilation under LT. Additionally, the relative conductivity (RC) and malondialdehyde (MDA) content were decreased, while the soluble protein content and superoxide dismutase (SOD) activity were increased with the application of USL under LT, thereby causing a reduction in membrane lipid peroxidation and alleviation of stress damage. These results suggest that light supplementation from underneath the canopy improves the cold resistance of tomato seedlings mainly by alleviating the degree of photoinhibition on photosystems, improving the activity of the photochemical reaction center, and enhancing the activities of antioxidant enzymes, thereby promoting the growth and stress resistance of tomato plants.
PMID: 35498645
Front Plant Sci , IF:5.753 , 2022 , V13 : P856527 doi: 10.3389/fpls.2022.856527
Antioxidant Regulation and DNA Methylation Dynamics During Mikania micrantha Seed Germination Under Cold Stress.
School of Life Sciences, Sun Yat-sen University, Guangzhou, China.; Research Institute of Sun Yat-sen University in Shenzhen, Shenzhen, China.; College of Life Sciences, South China Agricultural University, Guangzhou, China.
As a primary goal, adaptation to cold climate could expand an invasion range of exotic plants. Here, we aimed to explore the regulation strategy of M. micrantha seed development under cold stress through molecular physiology and multi-omics analysis. Significant increase of hydrogen peroxide, malondialdehyde, and electrolyte leakage observed under cold stress revealed that oxidative damage within M. micrantha seed cells was induced in the initial germination phase. Proteomic data underscored an activation of antioxidant activity to maintain redox homeostasis, with a cluster of antioxidant proteins identified. Genomic-wide transcriptome, in combination with time-series whole-genome bisulfite sequencing mining, elucidated that seven candidate genes, which were the target of DNA demethylation-dependent ROS scavenging, were possibly associated with an M. micrantha germ break. Progressive gain of CHH context DNA methylation identified in an early germination phrase suggested a role of a DNA methylation pathway, while an active DNA demethylation pathway was also initiated during late seed development, which was in line with the expression trend of methylation and demethylation-related genes verified through qRT-PCR. These data pointed out that cold-dependent DNA demethylation and an antioxidant regulatory were involved together in restoring seed germination. The expression level of total 441 genes presented an opposite trend to the methylation divergence, while the expression of total 395 genes was proved to be negatively associated with their methylation levels. These data provided new insights into molecular reprograming events during M. micrantha seed development.
PMID: 35463422
Front Plant Sci , IF:5.753 , 2022 , V13 : P891488 doi: 10.3389/fpls.2022.891488
Acquisition of Freezing Tolerance in Vaccinium macrocarpon Ait. Is a Multi-Factor Process Involving the Presence of an Ice Barrier at the Bud Base.
Arnold Arboretum of Harvard University, Boston, MA, United States.; Department of Horticulture, University of Wisconsin-Madison, Madison, WI, United States.; Department of Crop and Soil Sciences, USDA-ARS and North Carolina State University, Raleigh, NC, United States.
Bud freezing survival strategies have in common the presence of an ice barrier that impedes the propagation of lethally damaging ice from the stem into the internal structures of buds. Despite ice barriers' essential role in buds freezing stress survival, the nature of ice barriers in woody plants is not well understood. High-definition thermal recordings of Vaccinium macrocarpon Ait. buds explored the presence of an ice barrier at the bud base in September, January, and May. Light and confocal microscopy were used to evaluate the ice barrier region anatomy and cell wall composition related to their freezing tolerance. Buds had a temporal ice barrier at the bud base in September and January, although buds were only freezing tolerant in January. Lack of functionality of vascular tissues may contribute to the impedance of ice propagation. Pith tissue at the bud base had comparatively high levels of de-methyl-esterified homogalacturonan (HG), which may also block ice propagation. By May, the ice barrier was absent, xylogenesis had resumed, and de-methyl-esterified HG reached its lowest levels, translating into a loss of freezing tolerance. The structural components of the barrier had a constitutive nature, resulting in an asynchronous development of freezing tolerance between anatomical and metabolic adaptations.
PMID: 35599888
Theor Appl Genet , IF:5.699 , 2022 May doi: 10.1007/s00122-022-04117-9
OsWRKY115 on qCT7 links to cold tolerance in rice.
Key Laboratory of Germplasm Enhancement, Physiology and Ecology of Food Crops in Cold Region, Ministry of Education, Northeast Agricultural University, Harbin, 150030, China.; National Key Facility for Crop Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.; Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.; National Key Facility for Crop Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China. liujun@caas.cn.; Key Laboratory of Germplasm Enhancement, Physiology and Ecology of Food Crops in Cold Region, Ministry of Education, Northeast Agricultural University, Harbin, 150030, China. zoudtneau@126.com.
KEY MESSAGE: qCT7, a novel QTL for increasing seedling cold tolerance in rice, was fine-mapped to a 70.9-kb region on chromosome 7, and key OsWRKY115 was identified in transgenic plants. Cold stress caused by underground cold-water irrigation seriously limits rice productivity. We systemically measured the cold-responsive traits of 2,570 F2 individuals derived from two widely cultivated rice cultivars, Kong-Yu-131 and Dong-Nong-422, to identify the major genomic regions associated with cold tolerance. A novel major QTL, qCT7, was mapped on chromosome 7 associated with the cold tolerance and survival, using whole-genome re-sequencing with bulked segregant analysis. Local QTL linkage analysis with F2 and fine mapping with recombinant plant revealed a 70.9-kb core region on qCT7 encoding 13 protein-coding genes. Only the LOC_Os07g27670 expression level encoding the OsWRKY115 transcription factor on the locus was specifically induced by cold stress in the cold-tolerant cultivar. Moreover, haplotype analysis and the KASP8 marker indicated that OsWRKY115 was significantly associated with cold tolerance. Overexpression and knockout of OsWRKY115 significantly affected cold tolerance in seedlings. Our experiments identified OsWRKY115 as a novel regulatory gene associated with cold response in rice, and the Kong-Yu-131 allele with specific cold-induced expression may be an important molecular variant.
PMID: 35622122
Microbiol Res , IF:5.415 , 2022 Jul , V260 : P127049 doi: 10.1016/j.micres.2022.127049
Psychrotrophic plant beneficial bacteria from the glacial ecosystem of Sikkim Himalaya: Genomic evidence for the cold adaptation and plant growth promotion.
Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Post Box No. 06, Palampur 176 061, Himachal Pradesh, India; Department of Microbiology, Guru Nanak Dev University, Amritsar 143 005, Punjab, India.; Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Post Box No. 06, Palampur 176 061, Himachal Pradesh, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201 002, India.; Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Post Box No. 06, Palampur 176 061, Himachal Pradesh, India.; Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Post Box No. 06, Palampur 176 061, Himachal Pradesh, India. Electronic address: rakshak@ihbt.res.in.
Commercial biofertilizers tend to be ineffective in cold mountainous regions due to reduced metabolic activity of the microbial inoculants under low temperatures. Cold-adapted glacier bacteria with plant growth-promoting (PGP) properties may prove significant in developing cold-active biofertilizers for improving mountain agriculture. With this perspective, the cultivable bacterial diversity was documented from the East Rathong glacier ecosystem lying above 3900 masl of Sikkim Himalaya. A total of 120 bacterial isolates affiliated to Gammaproteobacteria (53.33%), Bacteroidetes (16.66%), Actinobacteria (15.83%), Betaproteobacteria (6.66%), Alphaproteobacteria (4.16%), and Firmicutes (3.33%) were recovered. Fifty-two isolates showed many in vitro PGP activities of phosphate solubilization (9-100 microg/mL), siderophore production (0.3-100 psu) and phytohormone indole acetic acid production (0.3-139 microg/mL) at 10 degrees C. Plant-based bioassays revealed an enhancement of shoot length by 21%, 22%, and 13% in ERGS5:01, ERMR1:04, and ERMR1:05, and root length by 14%, 17%, 11%, and 22% in ERGS4:06, ERGS5:01, ERMR1:04, and ERMR1:05 treated seeds respectively. An increased shoot dry weight of 4-29% in ERMR1:05 and ERMR1:04, and root dry weight of 42-98% was found in all the treatments. Genome analysis of four bacteria from diverse genera predicted many genes involved in the bacterial PGP activity. Comparative genome study highlighted the presence of PGP-associated unique genes for glucose dehydrogenase, siderophore receptor, tryptophan synthase, phosphate metabolism (phoH, P, Q, R, U), nitrate and nitrite reductase, TonB-dependent receptor, spermidine/putrescine ABC transporter etc. in the representative bacteria. The expression levels of seven cold stress-responsive genes in the cold-adapted bacterium ERGS4:06 using real-time quantitative PCR (RT-qPCR) showed an upregulation of all these genes by 6-17% at 10 degrees C, and by 3-33% during cold-shock, which indicates the cold adaptation strategy of the bacterium. Overall, this study signifies the psychrotrophic bacterial diversity from an extreme glacier environment as a potential tool for improving plant growth under cold environmental stress.
PMID: 35504236
Plant Methods , IF:4.993 , 2022 May , V18 (1) : P62 doi: 10.1186/s13007-022-00886-y
Overexpressing Arabidopsis thaliana ACBP6 in transgenic rapid-cycling Brassica napus confers cold tolerance.
Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia.; School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China.; School of BioSciences, The University of Melbourne, Parkville, VIC, Australia.; Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia. paulwjt@unimelb.edu.au.
BACKGROUND: Rapid-cycling Brassica napus (B. napus-RC) has potential as a rapid trait testing system for canola (B. napus) because its life cycle is completed within 2 months while canola usually takes 4 months, and it is susceptible to the same range of diseases and abiotic stress as canola. However, a rapid trait testing system for canola requires the development of an efficient transformation and tissue culture system for B. napus-RC. Furthermore, effectiveness of this system needs to be demonstrated by showing that a particular trait can be rapidly introduced into B. napus-RC plants. RESULTS: An in-vitro regeneration protocol was developed for B. napus-RC using 4-day-old cotyledons as the explant. High regeneration percentages, exceeding 70%, were achieved when 1-naphthaleneacetic acid (0.10 mg/L), 6-benzylaminopurine (1.0 mg/L), gibberellic acid (0.01 mg/L) and the ethylene antagonist silver nitrate (5 mg/L) were included in the regeneration medium. An average transformation efficiency of 16.4% was obtained using Agrobacterium-mediated transformation of B. napus-RC cotyledons using Agrobacterium strain GV3101 harbouring a plasmid with an NPTII (kanamycin-selectable) marker gene and the Arabidopsis thaliana cDNA encoding ACYL-COA-BINDING PROTEIN6 (AtACBP6). Transgenic B. napus-RC overexpressing AtACBP6 displayed better tolerance to freezing/frost than the wild type, with enhanced recovery from cellular membrane damage at both vegetative and flowering stages. AtACBP6-overexpressing B. napus-RC plants also exhibited lower electrolyte leakage and improved recovery following frost treatment, resulting in higher yields than the wild type. Ovules from transgenic AtACBP6 lines were better protected from frost than those of the wild type, while the developing embryos of frost-treated AtACBP6-overexpressing plants showed less freezing injury than the wild type. CONCLUSIONS: This study demonstrates that B. napus-RC can be successfully regenerated and transformed from cotyledon explants and has the potential to be an effective trait testing platform for canola. Additionally, AtACBP6 shows potential for enhancing cold tolerance in canola however, larger scale studies will be required to further confirm this outcome.
PMID: 35546678
Metabolites , IF:4.932 , 2022 Apr , V12 (5) doi: 10.3390/metabo12050392
Metabolomics Reveals 5-Aminolevulinic Acid Improved the Ability of Tea Leaves (Camellia sinensis L.) against Cold Stress.
Shaanxi Provincial Bioresource Key Laboratory, College of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong 723000, China.; Qinling-Bashan Mountains Bioresources Comprehensive Development C. I. C, Hanzhong 723001, China.; Qinba State Key Laboratory of Biological Resources and Ecological Environment, Hanzhong 723001, China.; Department of Human Nutrition, Food and Animal Sciences, College of Tropical Agriculture and Human Resources, University of Hawaii at Manoa, 1955 East-West Road, AgSci. 415J, Honolulu, HI 96822, USA.
Tea is an important woody crop whose cultivation is severely limited by cold stress. Although 5-aminolevulinic acid (ALA) is known to be effective in alleviating abiotic stresses in plants, knowledge of the detailed metabolic response of tea plants to exogenous ALA-induced cold resistance is still limited-a lack which restricts our ability to protect tea plants from cold stress. In the present study, we performed an in-depth metabolomics analysis to elucidate the metabolic responses of tea plants to cold stress and explore the role of ALA in improving tea plants' cold-resistance capability. Metabolic profiles showed that cold stress altered various metabolisms in tea plants, especially galactose composition and flavonoid contents. Furthermore, exogenous ALA application altered a series of metabolisms associated with cold stress. Importantly, increases in metabolites, including catechin, 3,4-dihydroxyphenylacetic acid and procyanidin B2, involved in the mechanisms of ALA improved tea plants' cold resistance. Overall, our study deciphered detailed metabolic responses of tea plants to cold stress and elucidated the mechanisms of ALA in enhancing cold resistance through rebuilding compositions of soluble carbohydrates and flavonoids. Therefore, we have provided a basis for exogenous usage of ALA to protect tea plants from cold stress.
PMID: 35629897
Plant Sci , IF:4.729 , 2022 May , V318 : P111242 doi: 10.1016/j.plantsci.2022.111242
Proteomic analysis reveals the molecular mechanism underlying the cold acclimation and freezing tolerance of wheat (Triticum aestivum L.).
State Key Laboratory of North China Crop Improvement and Regulation, North China Key Laboratory for Crop Germplasm Resources of Education Ministry, Hebei Agricultural University, Baoding 071000, Hebei, China.; State Key Laboratory of North China Crop Improvement and Regulation, North China Key Laboratory for Crop Germplasm Resources of Education Ministry, Hebei Agricultural University, Baoding 071000, Hebei, China. Electronic address: zhaoyong_0423@163.com.; Hebei University, Baoding 071000, Hebei, China.; State Key Laboratory of North China Crop Improvement and Regulation, North China Key Laboratory for Crop Germplasm Resources of Education Ministry, Hebei Agricultural University, Baoding 071000, Hebei, China; Cangzhou Academy of Agriculture and Forestry Sciences, Cangzhou 061001, Hebei, China.; State Key Laboratory of North China Crop Improvement and Regulation, North China Key Laboratory for Crop Germplasm Resources of Education Ministry, Hebei Agricultural University, Baoding 071000, Hebei, China. Electronic address: shmyxj@126.com.
Cold acclimation (CA) is an important evolutionary adaptive mechanism for wheat freezing resistence. To clarify the molecular basis of wheat CA and freezing tolerance, the effects of CA (4 degrees C) and non-CA (20 degrees C) treatments and freezing stress (-5 degrees C) on the proteins in the wheat crown were characterized via an iTRAQ-based proteomic analysis. A total of 669 differentially accumulated proteins (DAPs) were identified after the CA, of which seven were also DAPs in the CA plants exposed to freezing stress. Additionally, the 15 DAPs in the CA group and the 23 DAPs in the non-CA group after the freezing treatment differed substantially. Functional analyses indicated that CA enhanced freezing tolerance by regulating proteins involved in signal transduction, carbohydrate metabolism, stress and defense responses, and phenylpropanoid biosynthesis. An integrated transcriptomic, proteomic, and metabolomic analysis revealed significant changes in various components of the glutathione metabolic pathway. The overexpression and silencing of Wdhn13 in Arabidopsis and wheat resulted in increased tolerance and sensitivity to freezing stress, respectively, suggesting Wdhn13 promotes freezing tolerance. Overall, our study offers insights into the regulatory network underlying the CA and freezing tolerance of wheat, which may be useful for elucidating wheat freezing resistance.
PMID: 35351310
Front Genet , IF:4.599 , 2022 , V13 : P870446 doi: 10.3389/fgene.2022.870446
Small RNA Sequencing Revealed that miR4415, a Legume-Specific miRNA, was Involved in the Cold Acclimation of Ammopiptanthus nanus by Targeting an L-Ascorbate Oxidase Gene and Regulating the Redox State of Apoplast.
Key Laboratory of Ecology and Environment in Minority Areas, National Ethnic Affairs Commission, Minzu University of China, Beijing, China.; Key Laboratory of Mass Spectrometry Imaging and Metabolomics, National Ethnic Affairs Commission, Minzu University of China, Beijing, China.; College of Life and Environmental Sciences, Minzu University of China, Beijing, China.; Beijing Center for Disease Prevention and Control, Beijing, China.
MicroRNAs (miRNAs) are small endogenous single-stranded RNAs that regulate plant growth, development, and environmental stress response posttranscriptionally. Ammopiptanthus nanus, a rare evergreen broad-leaved shrub in the temperate area of Central Asia, can tolerate freezing stress as low as -30 degrees centigrade in winter, and miRNA might be involved in the cold acclimation which enables A. nanus to obtain tolerance to freezing stress. Systematic identification and functional analysis of the miRNAs involved in the cold acclimation in A. nanus may promote understanding of the miRNA-mediated gene regulation network underlying cold acclimation. Here, based on small RNA and degradome sequencing, 256 miRNAs and 1,808 miRNA-target pairs were identified in A. nanus. A total of 39 cold-responsive miRNAs were identified, of which 29 were upregulated and ten were downregulated. These cold-responsive miRNAs may participate in the cold acclimation by regulating redox homeostasis (miR398, miR4415, and miR408), calcium signaling (miR5225 and miR5211), growth and development (miR159 and miR390), and small RNA-mediated gene silencing (miR168 and miR1515). We found that miR4415, a legume-specific miRNA, is involved in the cold acclimation of A. nanus by targeting an L-ascorbate oxidase gene and then regulating the redox state of the apoplast. Our study provides important data for understanding the regulatory role of miRNA in the cold acclimation of A. nanus.
PMID: 35444684
BMC Plant Biol , IF:4.215 , 2022 Apr , V22 (1) : P211 doi: 10.1186/s12870-022-03609-6
Genome-wide identification and expression analysis of the SWEET gene family in daylily (Hemerocallis fulva) and functional analysis of HfSWEET17 in response to cold stress.
School of Ecological Technology and Engineering, Shanghai Institute of Technology, Shanghai, 201418, China.; School of Ecological Technology and Engineering, Shanghai Institute of Technology, Shanghai, 201418, China. qinqp@sit.edu.cn.
BACKGROUND: The Sugars Will Eventually be Exported Transporters (SWEETs) are a newly discovered family of sugar transporters whose members exist in a variety of organisms and are highly conserved. SWEETs have been reported to be involved in the growth and development of many plants, but little is known about SWEETs in daylily (Hemerocallis fulva), an important perennial ornamental flower. RESULTS: In this study, 19 daylily SWEETs were identified and named based on their homologous genes in Arabidopsis and rice. Phylogenetic analysis classified these HfSWEETs into four clades (Clades I to IV). The conserved motifs and gene structures showed that the HfSWEETs were very conservative during evolution. Chromosomal localization and synteny analysis found that HfSWEETs were unevenly distributed on 11 chromosomes, and there were five pairs of segmentally duplicated events and one pair of tandem duplication events. The expression patterns of the 19 HfSWEETs showed that the expression patterns of most HfSWEETs in different tissues were related to corresponding clades, and most HfSWEETs were up-regulated under low temperatures. Furthermore, HfSWEET17 was overexpressed in tobacco, and the cold resistance of transgenic plants was much higher than that of wild-type tobacco. CONCLUSION: This study identified the SWEET gene family in daylily at the genome-wide level. Most of the 19 HfSWEETs were expressed differently in different tissues and under low temperatures. Overexpression further suggests that HfSWEET17 participates in daylily low-temperature response. The results of this study provide a basis for further functional analysis of the SWEET family in daylily.
PMID: 35468723
BMC Plant Biol , IF:4.215 , 2022 Apr , V22 (1) : P209 doi: 10.1186/s12870-022-03578-w
Comparative transcriptomic analyses of citrus cold-resistant vs. sensitive rootstocks might suggest a relevant role of ABA signaling in triggering cold scion adaption.
Centro de Citricultura y Produccion Vegetal, Instituto Valenciano de Investigaciones Agrarias (IVIA), Valencia, Spain. primo_amp@gva.es.; Centro de Citricultura y Produccion Vegetal, Instituto Valenciano de Investigaciones Agrarias (IVIA), Valencia, Spain.; Centro de Genomica, Instituto Valenciano de Investigaciones Agrarias (IVIA), Valencia, Spain.
BACKGROUND: The citrus genus comprises a number of sensitive tropical and subtropical species to cold stress, which limits global citrus distribution to certain latitudes and causes major economic loss. We used RNA-Seq technology to analyze changes in the transcriptome of Valencia delta seedless orange in response to long-term cold stress grafted on two frequently used citrus rootstocks: Carrizo citrange (CAR), considered one of the most cold-tolerant accessions; C. macrophylla (MAC), a very sensitive one. Our objectives were to identify the genetic mechanism that produce the tolerant or sensitive phenotypes in citrus, as well as to gain insights of the rootstock-scion interactions that induce the cold tolerance or sensitivity in the scion. RESULTS: Plants were kept at 1 masculineC for 30 days. Samples were taken at 0, 15 and 30 days. The metabolomic analysis showed a significant increase in the concentration of free sugars and proline, which was higher for the CAR plants. Hormone quantification in roots showed a substantially increased ABA concentration during cold exposure in the CAR roots, which was not observed in MAC. Different approaches were followed to analyze gene expression. During the stress treatment, the 0-15-day comparison yielded the most DEGs. The functional characterization of DEGs showed enrichment in GO terms and KEGG pathways related to abiotic stress responses previously described in plant cold adaption. The DEGs analysis revealed that several key genes promoting cold adaption were up-regulated in the CAR plants, and those repressing it had higher expression levels in the MAC samples. CONCLUSIONS: The metabolomic and transcriptomic study herein performed indicates that the mechanisms activated in plants shortly after cold exposure remain active in the long term. Both the hormone quantification and differential expression analysis suggest that ABA signaling might play a relevant role in promoting the cold hardiness or sensitiveness of Valencia sweet orange grafted onto Carrizo citrange or Macrophylla rootstocks, respectively. Our work provides new insights into the mechanisms by which rootstocks modulate resistance to abiotic stress in the production variety grafted onto them.
PMID: 35448939
Planta , IF:4.116 , 2022 May , V256 (1) : P2 doi: 10.1007/s00425-022-03915-1
Identification of the DcHsp20 gene family in carnation (Dianthus caryophyllus) and functional characterization of DcHsp17.8 in heat tolerance.
College of Landscape and Forestry, Qingdao Agricultural University, No.100, Changcheng Road, Chengyang District, Qingdao, 266109, Shandong, People's Republic of China.; College of Landscape and Forestry, Qingdao Agricultural University, No.100, Changcheng Road, Chengyang District, Qingdao, 266109, Shandong, People's Republic of China. wanxueli@qau.edu.cn.
MAIN CONCLUSION: 33 heat shock protein 20 (Hsp20) genes were identified from the carnation genome whose expression were altered by abiotic stresses. DcHsp17.8 may function to improve the heat resistance of Arabidopsis. Heat shock proteins 20 (Hsp20s) mainly function as molecular chaperones that play crucial roles in relieving abiotic stresses such as heat stress. In this study, we identified and characterized 33 DcHsp20 genes from the carnation genome that were classified into 9 subfamilies. Gene structure analysis showed that 25 DcHsp20 genes contained 1 intron whilst the remaining 8 DcHsp20 genes did not contain introns. Motif analysis found that DcHsp20 proteins were relatively conserved. Cis-regulatory elements analysis of the Hsp20 promoters revealed a number of cis-regulatory elements that regulate growth and development, hormone and stress responses. Gene expression analysis revealed that DcHsp20 genes had multiple response patterns to heat stress. The largest range of induction occurred in DcHsp17.8 after 1 h of heat stress. Under cold stress, or treatment with saline or abscisic acid, the expression of most DcHsp20 genes was inhibited. To further understand the function of DcHsp20 genes in response to heat stress, we overexpressed DcHsp17.8 in Arabidopis and the plants showed improved heat tolerance, O2(-) and H2O2 activities and photosynthetic capacity with reduced relative electrolyte leakage and malondialdehyde content. Gene expression analysis revealed that DcHsp17.8 modulated the expression of genes involved in antioxidant enzyme synthesis. Our data provided a solid foundation for the further detailed study of DcHsp20 genes.
PMID: 35624182
Phytopathology , IF:4.025 , 2022 May , V112 (5) : P1134-1140 doi: 10.1094/PHYTO-07-21-0287-R
Rhizoctonia Resistance Is Negatively Correlated to Early Root Growth Rate in Synthetic Hexaploid Wheat Derivatives.
U.S. Department of Agriculture Agricultural Research Service, Wheat Health, Genetics and Quality Research Unit, Pullman, WA 99164-6430.; Molecular Plant Sciences Program, Washington State University, Pullman, WA 99164-1030.; Department of Crop and Soil Sciences, Washington State University, Pullman, WA 99164-6420.
Resistance to the soilborne fungal pathogen Rhizoctonia solani AG-8 is desirable in adapted wheat and barley but remains an elusive trait for prebreeders and breeders. In a previous study, we observed that emergence and root growth was faster in the Rhizoctonia-susceptible 'Scarlet' than in its resistant counterpart, 'Scarlet-Rz1'. The objective of the current study was to quantify early root growth rate and total root length in resistant and susceptible synthetic hexaploid wheat lines, including parental lines and 22 recombinant inbred lines derived crosses between parental lines. In Petri dish assays, the susceptible lines displayed a faster rate of root growth during the first 40 h of root emergence compared with resistant lines. This growth differential was observed in 14-day and 48-h greenhouse assays, in which the total root length of susceptible parental lines was significantly (P < 0.05) greater than that of resistant parental lines. However, the resistant lines sustained less root loss compared with susceptible lines when R. solani AG-8 was present in the soil. Early root growth rate and total root length were not correlated to freezing tolerance in a set of wheat cultivars selected for cold tolerance. The findings indicated that early root growth was negatively correlated to R. solani AG-8 damage in resistant synthetic wheat lines developed for the Pacific Northwest, United States, and suggested that the dynamics of root emergence affect resistance to this soilborne pathogen.
PMID: 35378055
BMC Genomics , IF:3.969 , 2022 Apr , V23 (1) : P280 doi: 10.1186/s12864-022-08526-4
Physiological attributes and transcriptomics analyses reveal the mechanism response of Helictotrichon virescens to low temperature stress.
Institute of qinghai-tibetan Plateau, Southwest Minzu University, Chengdu, 610041, China.; Sichuan Grass Industry Technology Research and Promotion Center, Chengdu, 610041, China.; Sichuan Agricultural Technology Extension Station, Chengdu, 610041, China.; College of Chemistry and Life Sciences, Chengdu Normal University, Chengdu, 611130, China.; Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, China.; Institute of Agricultural Information and Rural Economy, Sichuan Academy of Agricultural Sciences, Sichuan, Chengdu, 610066, China.; Maize Research Institute, Sichuan Agricultural University, Chengdu, 611130, China. 243535990@qq.com.
BACKGROUND: Helictotrichon virescens is a perennial grass that is primarily distributed in high altitude areas of 2000 ~ 4500 m. It is widely cultivated in the Qinghai-Tibet Plateau of China, strongly resistant to cold, and an essential part of the wild herbs in this region. However, the molecular mechanism of the response of H. virescens to low temperature stress and the key regulatory genes for specific biological processes are poorly understood. RESULTS: Physiological and transcriptome analyses were used to study the cold stress response mechanism in H virescens. During the low temperature stress period, the content of chlorophyll a and b decreased more and more with the delay of the treatment time. Among them, the difference between the controls was not significant, and the difference between the control and the treatment was significant. At the same time, the expression of related differential genes was up-regulated during low temperature treatment. In addition, the plant circadian pathway is crucial for their response to cold stress. The expression of differentially expressed genes that encode LHY and HY5 were strongly up-regulated during cold stress. CONCLUSIONS: This study should help to fully understand how H. virescens responds to low temperatures. It answers pertinent questions in the response of perennial herbs to cold stress, i.e., how light and low temperature signals integrate to regulate plant circadian rhythms and Decrease of content of chlorophylls (which can be also accompanied with decrease of total quantity of reaction centers) leads to an increase in photosynthetic damage.
PMID: 35392804
Plants (Basel) , IF:3.935 , 2022 May , V11 (10) doi: 10.3390/plants11101364
The Effect of Cold Stress on the Root-Specific Lipidome of Two Wheat Varieties with Contrasting Cold Tolerance.
Biotechnology Research Institute, Universiti Malaysia Sabah, Jalan Universiti, Kota Kinabalu 88400, Malaysia.; School of Bio Sciences, The University of Melbourne, Parkville, VIC 3010, Australia.; Protein Chemistry and Metabolism Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC 3065, Australia.; Max-Planck-Institute of Molecular Plant Physiology, Am Muhlenberg 1, 14476 Potsdam, Germany.; Advanced Genomics Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052, Australia.; SCIEX, Mulgrave, VIC 3170, Australia.; CSIRO Agriculture & Food, GPO Box 1700, Canberra, ACT 2601, Australia.; Research School of Biology, The Australian National University, Acton, ACT 2601, Australia.
Complex glycerolipidome analysis of wheat upon low temperature stress has been reported for above-ground tissues only. There are no reports on the effects of cold stress on the root lipidome nor on tissue-specific responses of cold stress wheat roots. This study aims to investigate the changes of lipid profiles in the different developmental zones of the seedling roots of two wheat varieties with contrasting cold tolerance exposed to chilling and freezing temperatures. We analyzed 273 lipid species derived from 21 lipid classes using a targeted profiling approach based on MS/MS data acquired from schedule parallel reaction monitoring assays. For both the tolerant Young and sensitive Wyalkatchem species, cold stress increased the phosphatidylcholine and phosphatidylethanolamine compositions, but decreased the monohexosyl ceramide compositions in the root zones. We show that the difference between the two varieties with contrasting cold tolerance could be attributed to the change in the individual lipid species, rather than the fluctuation of the whole lipid classes. The outcomes gained from this study may advance our understanding of the mechanisms of wheat adaptation to cold and contribute to wheat breeding for the improvement of cold-tolerance.
PMID: 35631789
Plants (Basel) , IF:3.935 , 2022 May , V11 (10) doi: 10.3390/plants11101351
Crosstalk between Ca(2+) and Other Regulators Assists Plants in Responding to Abiotic Stress.
Biomedicine Collaborative Innovation Center of Zhejiang Province, Institute of Life Sciences, College of Life and Environmental Science, Wenzhou University, Wenzhou 325035, China.
Plants have evolved many strategies for adaptation to extreme environments. Ca(2+), acting as an important secondary messenger in plant cells, is a signaling molecule involved in plants' response and adaptation to external stress. In plant cells, almost all kinds of abiotic stresses are able to raise cytosolic Ca(2+) levels, and the spatiotemporal distribution of this molecule in distant cells suggests that Ca(2+) may be a universal signal regulating different kinds of abiotic stress. Ca(2+) is used to sense and transduce various stress signals through its downstream calcium-binding proteins, thereby inducing a series of biochemical reactions to adapt to or resist various stresses. This review summarizes the roles and molecular mechanisms of cytosolic Ca(2+) in response to abiotic stresses such as drought, high salinity, ultraviolet light, heavy metals, waterlogging, extreme temperature and wounding. Furthermore, we focused on the crosstalk between Ca(2+) and other signaling molecules in plants suffering from extreme environmental stress.
PMID: 35631776
Plants (Basel) , IF:3.935 , 2022 Apr , V11 (9) doi: 10.3390/plants11091217
Effects of Chilling Stress on Morphological, Physiological, and Biochemical Attributes of Silage Corn Genotypes during Seedling Establishment.
School of Science and the Environment, Grenfell Campus, Memorial University of Newfoundland and Labrador, Corner Brook, NL A2H 5G4, Canada.
Chilling stress is one of the major abiotic stresses which hinder seedling emergence and growth. Herein, we investigated the effects of chilling/low temperature stress on the morphological, physiological, and biochemical attributes of two silage corn genotypes during the seedling establishment phase. The experiment was conducted in a growth chamber, and silage corn seedlings of Yukon-R and A4177G-RIB were grown at optimum temperature up to V3 stage and then subjected to five temperature regimes (25 degrees C as control, 20 degrees C, 15 degrees C, 10 degrees C, and 5 degrees C) for 5 days. After the temperature treatment, the morphological, physiological, and biochemical parameters were recorded. Results indicated that temperatures of 15 degrees C and lower significantly affected seedling growth, photosynthesis system, reactive oxygen species (ROS) accumulation, and antioxidant enzyme activities. Changes in seedlings' growth parameters were in the order of 25 degrees C > 20 degrees C > 15 degrees C > 10 degrees C > 5 degrees C, irrespective of genotypes. The chlorophyll content, photosynthetic rate, and maximal photochemical efficiency of PS-II (Fv/Fm) were drastically decreased under chilling conditions. Moreover, chilling stress induced accumulation of hydrogen peroxide (H2O2)and malonaldehyde (MDA) contents. Increased proline content and enzymatic antioxidants, including superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxide (APX), were found to alleviate oxidative damage under chilling stress. However, the genotype of Yukon-R exhibited better adaption to chilling stress than A4177G3-RIB. Yukon-R showed significantly higher proline content and enzymatic antioxidant activities than A4177G3-RIB under severe chilling conditions (temperature
PMID: 35567218
Plants (Basel) , IF:3.935 , 2022 Apr , V11 (9) doi: 10.3390/plants11091105
Stochastic Variation in DNA Methylation Modulates Nucleosome Occupancy and Alternative Splicing in Arabidopsis thaliana.
School of Biosciences and Medicine, University of Surrey, Guildford GU2 7XH, UK.; School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK.; Life Sciences Industry Liaison Lab, School of Psychology and Life Sciences, Canterbury Christ Church University, Sandwich CT13 9ND, UK.; RNA Biology and Molecular Physiology, Faculty of Biology, Bielefeld University, 33615 Bielefeld, Germany.; School of Human and Life Sciences, Canterbury Christ Church University, Canterbury CT1 1QU, UK.
Plants use complex gene regulatory mechanisms to overcome diverse environmental challenges. For instance, cold stress induces rapid and massive transcriptome changes via alternative splicing (AS) to confer cold tolerance in plants. In mammals, mounting evidence suggests chromatin structure can regulate co-transcriptional AS. Recent evidence also supports co-transcriptional regulation of AS in plants, but how dynamic changes in DNA methylation and the chromatin structure influence the AS process upon cold stress remains poorly understood. In this study, we used the DNA methylation inhibitor 5-Aza-2'-Deoxycytidine (5-aza-dC) to investigate the role of stochastic variations in DNA methylation and nucleosome occupancy in modulating cold-induced AS, in Arabidopsis thaliana (Arabidopsis). Our results demonstrate that 5-aza-dC derived stochastic hypomethylation modulates nucleosome occupancy and AS profiles of genes implicated in RNA metabolism, plant hormone signal transduction, and of cold-related genes in response to cold stress. We also demonstrate that cold-induced remodelling of DNA methylation regulates genes involved in amino acid metabolism. Collectively, we demonstrate that sudden changes in DNA methylation via drug treatment can influence nucleosome occupancy levels and modulate AS in a temperature-dependent manner to regulate plant metabolism and physiological stress adaptation.
PMID: 35567106
Plants (Basel) , IF:3.935 , 2022 Apr , V11 (7) doi: 10.3390/plants11070977
An Integration of MicroRNA and Transcriptome Sequencing Analysis Reveal Regulatory Roles of miRNAs in Response to Chilling Stress in Wild Rice.
College of Life Science and Technology, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning 530004, China.; Agriculture College, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning 530004, China.
A chromosome single segment substitution line (CSSL) DC90, which was generated by introgressing CTS-12, a locus derived from common wild rice (Oryza rufipogon Griff.), into the 9311 (Oryza sativa L. ssp. indica) background, exhibits a chilling tolerance phenotype under chilling stress. Here, an integration of microRNA (miRNA) deep sequencing and transcriptomic sequencing analysis was performed to explore the expression profiles of miRNAs and their target genes mediated by CTS-12 under chilling stress, and to reveal the possible regulatory mechanisms of miRNAs that are involved in chilling tolerance. Integration analysis revealed that a number of differentially expressed miRNAs (DEMs) and putative target genes with different expression patterns and levels were identified in 9311 and DC90 under chilling stress. KEGG enrichment analysis revealed that the target genes that are regulated by chilling-induced miRNAs are involved in the regulation of various biological processes/pathways, including protein biosynthesis, redox process, photosynthetic process, and chloroplast development in two genotypes. CRISPR/Cas9 editing of the target genes of the key DEMs in a chilling tolerant rice variety Zhonghua 11 (ZH11) found that LOC_Os11g48020 (OsGL1-11), one of the putative target genes of osa-miR1846a/b-5p and encoding a wax synthesis protein, is correlated with a chilling stress tolerance phenotype, implying osa-miR1846a/b-5p/OsGL1-11 plays an important role in CTS-12-mediated chilling stress tolerance regulatory pathway(s). Therefore, we speculate that the CTS-12 may regulate the key miRNA target genes in response to chilling stress by differential regulation of miRNAs in wild rice, thereby resulting in the variation of chilling tolerance phenotype between 9311 and DC90.
PMID: 35406957
Plants (Basel) , IF:3.935 , 2022 May , V11 (9) doi: 10.3390/plants11091262
Bryophyte Spores Tolerate High Desiccation Levels and Exposure to Cryogenic Temperatures but Contain Storage Lipids and Chlorophyll: Understanding the Essential Traits Needed for the Creation of Bryophyte Spore Banks.
Seed and Stress Biology, Royal Botanic Gardens Kew, Wakehurst Place, Ardingly RH17 6TN, West Sussex, UK.; Dipartimento di Agraria, Universita degli Studi di Sassari, 07100 Sassari, Sardinia, Italy.; Departamento de Botanica y geologia, Universitat de Valencia, 46100 Burjassot, Valencia, Spain.
Understanding the desiccation and freezing tolerance of bryophyte spores is vital to explain how plants conquered land and current species distribution patterns and help to develop efficient ex situ conservation methods. However, knowledge of these traits is scarce. We investigated tolerance to drying (at 15% relative humidity [RH] for two weeks) and freezing (1 h exposure to liquid nitrogen) on the spores of 12 bryophyte species (23 accessions) from the UK. The presence of storage lipids and their thermal fingerprint, and the levels of unfrozen water content, were determined by differential scanning calorimetry (DSC). The presence of chlorophyll in dry spores was detected by fluorescence microscopy. All species and accessions tested tolerated the drying and freezing levels studied. DSC suggested that 4.1-29.3% of the dry mass is storage lipids, with crystallization and melting temperatures peaking at around -30 degrees C. Unfrozen water content was determined <0.147 g H2O g(-1) dry weight (DW). Most of the spores investigated showed the presence of chlorophyll in the cytoplasm by red autofluorescence. Bryophyte spores can be stored dry at low temperatures, such as orthodox seeds, supporting the creation of bryophyte spore banks. However, the presence of storage lipids and chlorophyll in the cytoplasm may reduce spore longevity during conventional storage at -20 degrees C. Alternatively, cryogenic spore storage is possible.
PMID: 35567263
Plants (Basel) , IF:3.935 , 2022 Apr , V11 (8) doi: 10.3390/plants11081027
Insight into Carbohydrate Metabolism and Signaling in Grapevine Buds during Dormancy Progression.
Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via delle Scienze 206, 33100 Udine, Italy.
Perennial fruit crops enter dormancy to ensure bud tissue survival during winter. However, a faster phenological advancement caused by global warming exposes bud tissue to a higher risk of spring frost damage. Tissue dehydration and soluble sugars accumulation are connected to freezing tolerance, but non-structural carbohydrates also act as metabolic substrates and signaling molecules. A deepened understanding of sugar metabolism in the context of winter freezing resistance is required to gain insight into adaptive possibilities to cope with climate changes. In this study, the soluble sugar content was measured in a cold-tolerant grapevine hybrid throughout the winter season. Moreover, the expression of drought-responsive hexose transporters VvHT1 and VvHT5, raffinose synthase VvRS and grapevine ABA-, Stress- and Ripening protein VvMSA was analyzed. The general increase in sugars in December and January suggests that they can participate in protecting bud tissues against low temperatures. The modulation of VvHT5, VvINV and VvRS appeared consistent with the availability of the different sugar species; challenging results were obtained for VvHT1 and VvMSA, suggesting interesting hypotheses about their role in the sugar-hormone crosstalk. The multifaceted role of sugars on the intricate phenomenon, which is the response of dormant buds to changing temperature, is discussed.
PMID: 35448755
Gene , IF:3.688 , 2022 Jul , V830 : P146503 doi: 10.1016/j.gene.2022.146503
Full length transcriptomes analysis of cold-resistance of Apis cerana in Changbai Mountain during overwintering period.
Institute of Special Animal and Plant Sciences of Chinese Academy of Agricultural Sciences, Changchun, Jilin 130112, PR China; Apiculture Science Institute of Jilin Province, Jilin, Jilin 132108, PR China. Electronic address: liunannan7@163.com.; Jilin Institute of Chemical Technology, Jilin, Jilin 132022, PR China.; Jilin Provincial Animal Husbandry General Station, Changchun, Jilin 130699, PR China.; Apiculture Science Institute of Jilin Province, Jilin, Jilin 132108, PR China.; Apiculture Science Institute of Jilin Province, Jilin, Jilin 132108, PR China. Electronic address: 1463199779@qq.com.; Institute of Special Animal and Plant Sciences of Chinese Academy of Agricultural Sciences, Changchun, Jilin 130112, PR China. Electronic address: xingxiumei2004@126.com.
Apis cerana in Changbai Mountain is an ecological type of Apis cerana, which is an excellent breeding material with cold-resistant developed by long-term natural selection under the ecological conditions. However, the physiological and molecular mechanisms of Changbai Mountain population under cold stress are still unclear. In this study, the Nanopore sequencing was carried out for the transcriptome of Apis cerana in Changbai Mountain in the coldest period of overwintering, which will provide a reference to the cold-resistant mechanism. We determined 5,941 complete ORF sequences, 1,193 lncRNAs, 619 TFs, 10,866 SSRs and functional annotations of 11,599 new transcripts. Our results showed that the myosin family and the C2H2 zinc finger protein transcription factor family possibly have significant impacts on the response mechanism of cold stress during overwintering. In addition, the cold environment alters genes expression profiles in honeybees via different AS and APA mechanisms. These altered genes in Hippo, Foxo, and MARK pathways help them counter the stress of cold in overwinter period. Our results might provide clues about the response of eastern honeybees to extreme cold, and reflect the possible genetic basis of physiological changes.
PMID: 35487395
Fungal Genet Biol , IF:3.495 , 2022 Apr : P103698 doi: 10.1016/j.fgb.2022.103698
Annotation survey and life-cycle transcriptomics of transcription factors in rust fungi (Pucciniales) identify a possible role for cold shock proteins in dormancy exit.
Universite de Lorraine, INRAE, IAM, F-54000 Nancy, France.; School of biological Sciences, University of Portsmouth, King Henry 1 Street, PO1 D2Y, Portsmouth, United Kingdom.; Universite de Lorraine, INRAE, IAM, F-54000 Nancy, France. Electronic address: Sebastien.duplessis@inrae.fr.
Fungi of the order Pucciniales are obligate plant biotrophs causing rust diseases. They exhibit a complex life cycle with the production of up to five spore types, infection of two unrelated hosts and an overwintering stage. Transcription factors (TFs) are key regulators of gene expression in eukaryote cells. In order to better understand genetic programs expressed during major transitions of the rust life cycle, we surveyed the complement of TFs in fungal genomes with an emphasis on Pucciniales. We found that despite their large gene numbers, rust genomes have a reduced repertoire of TFs compared to other fungi. The proportions of C2H2 and Zinc cluster -two of the most represented TF families in fungi- indicate differences in their evolutionary relationships in Pucciniales and other fungal taxa. The regulatory gene family encoding cold shock protein (CSP) showed a striking expansion in Pucciniomycotina with specific duplications in the order Pucciniales. The survey of expression profiles collected by transcriptomics along the life cycle of the poplar rust fungus revealed TF genes related to major biological transitions, e.g. response to environmental cues and host infection. Particularly, poplar rust CSPs were strongly expressed in basidia produced after the overwintering stage suggesting a possible role in dormancy exit. Expression during transition from dormant telia to basidia confirmed the specific expression of the three poplar rust CSP genes. Their heterologous expression in yeast improved cell growth after cold stress exposure, suggesting a probable regulatory function when the poplar rust fungus exits dormancy. This study addresses for the first time TF and regulatory genes involved in developmental transition in the rust life cycle opening perspectives to further explore molecular regulation in the biology of the Pucciniales.
PMID: 35483517
Protoplasma , IF:3.356 , 2022 May doi: 10.1007/s00709-022-01765-y
Comparative genomic analysis of the CPK gene family in Moso bamboo (Phyllostachys edulis) and the functions of PheCPK1 in drought stress.
Laboratory of Modern Biotechnology, School of Forestry and Landscape Architecture, Anhui Agricultural University, Hefei, 230036, China.; Laboratory of Modern Biotechnology, School of Forestry and Landscape Architecture, Anhui Agricultural University, Hefei, 230036, China. xiangyanahau@sina.com.
Calcium-dependent protein kinases (CPKs) play an important role in plant regulation of growth and development, and in the responses to biotic and abiotic stresses. In the present study, we analyzed Moso bamboo (Phyllostachys edulis) CPK genes and their closely related five gene families (Brachypodium distachyon, Hordeum vulgare L., Oryza sativa, Setaria italica, and Zea mays) comprehensively, including phylogenetic relationships, gene structures, and synteny analysis. Thirty Moso bamboo CPKs were divided into four subgroups; in each subgroup, the constituent parts of gene structure were relatively conserved. Furthermore, analysis of expression profiles showed that most PheCPK genes are significantly upregulated under drought and cold stress, especially PheCPK1. Overexpression of PheCPK1 in Arabidopsis reduced plant tolerance to drought stress, as determined through physiological analyses of the relative water content, relative electrical leakage, and malondialdehyde content. It also activated the expressions of stress-related genes. In addition, overexpression of PheCPK1 in Arabidopsis exhibited significantly decreased reactive oxygen species (ROS)-scavenging ability. Taken together, these results suggest that PheCPK1 may act as a negative regulator involved in the drought stress responses.
PMID: 35503386
Protoplasma , IF:3.356 , 2022 Apr doi: 10.1007/s00709-022-01767-w
Superoxide dismutase (SOD) family in durum wheat: promising candidates for improving crop resilience.
Biotechnology and Plant Improvement Laboratory, Centre of Biotechnology of Sfax (CBS), University of Sfax, B.P "1177" 3018, Sfax, Tunisia. tounsisana@ymail.com.; Laboratory of Microbial Biotechnology Enzymatic and Biomolecules, Centre of Biotechnology of Sfax (CBS), University of Sfax, P.O Box 1177, 3018, Sfax, Tunisia.; Biology Department, Faculty of Sciences of Sfax, University of Sfax, Sfax, Tunisia.; Laboratory of Legumes and Sustainable Agrosystem (L2AD), Center of Biotechnology of Borj-Cedria, BP901, 2050, HammamLif, Tunisia.; Biotechnology and Plant Improvement Laboratory, Centre of Biotechnology of Sfax (CBS), University of Sfax, B.P "1177" 3018, Sfax, Tunisia. faical.brini@cbs.rnrt.tn.; Biotechnology and Plant Improvement Laboratory, Centre of Biotechnology of Sfax (CBS), University of Sfax, B.P "1177" 3018, Sfax, Tunisia.
The SOD family has been extensively analyzed at genome wide level in several crops. However, little is known about this family in durum wheat. In this study, a total of 14 TdSOD genes were identified in whole durum wheat genome including 8 TdCu-ZnSODs, 2 TdMnSODs, and 4 TdFeSODs. In silico analysis evinced that TdSOD family members displayed a closer evolutionary relationship, similar gene structure and protein features with their homologs from other plant species. Furthermore, the analysis of their promoter regions revealed the presence of a great number of cis-regulatory elements related to plant development, abiotic and biotic stresses, phytohormones, and several potential binding sites for transcription factors. Interestingly, 3D structure analysis revealed that TdCu-ZnSOD2A-2 and TdCu-ZnSOD2B-2, belonging to the Cu-Zn group, were modeled as copper chaperone for SOD like their homologs from rice and Arabidopsis. The expression profile of eight TdSOD candidate genes was investigated under salt, drought, cold, and ABA treatments. Notably, TdCu-ZnSOD2A-1, TdFeSOD4A-1, and TdFeSOD7A-1 were significantly up-regulated under all stress treatments. On the other hand, TdCu-ZnSOD7B and TdMnSOD2B were strongly expressed in roots and leaves under cold stress and TdCu-ZnSOD2B-2 was particularly up-regulated in leaves under ABA treatment. Ultimately, these findings provide valuable information for the identification of attractive candidate genes to improve wheat resilience.
PMID: 35484428
DNA Cell Biol , IF:3.311 , 2022 May doi: 10.1089/dna.2021.1144
Characterization and Functional Analysis of ZmSWEET15a in Maize.
Crop Genetics and Breeding Lines, College of Life Sciences, Jilin Agricultural University, Changchun, China.; Department of Biotechnology, College of Agronomy, Jilin Agricultural University, Changchun, China.
The sugars will eventually be exported transporters (SWEETs) gene family is a new type of sugar transporters, which plays an important role in plant growth and development, physiological metabolism, and abiotic stress. In this study, we used quantitative real-time PCR to analyze the expression of ZmSWEET15a gene in different organs of maize and under different abiotic stresses. The results showed that ZmSWEET15a was expressed in roots, stems, leaves, and grains, with the highest expression level in leaves, which was highly correlated with leaf development. Under the treatment of polyethylene glycol (PEG), NaCl, H2O2, and abscisic acid stress, the expression of ZmSWEET15a was upregulated, while under the treatment of cold stress, the expression of ZmSWEET15a was inhibited. In sugar-specific experiments, we found that sucrose was the most effective carbon source for maize seed germination. The expression analysis of ZmSWEET15a in different carbon sources suggested that the expression of ZmSWEET15a was more likely to be induced by sucrose. Overexpression of ZmSWEET15a in maize plants could reduce the sucrose content in leaves and increase the sucrose content in grains. The heterologous expression of ZmSWEET15a in the yeast mutant strain SUSY7/ura indicated that ZmSWEET15a is a sucrose transporter and pH independent. This study provides new insight into sugar transport and carbohydrate partitioning in maize and other crops, and provide more genetic information for improving crop quality at the molecular level.
PMID: 35593918
Funct Plant Biol , IF:3.101 , 2022 Apr doi: 10.1071/FP21297
Identification and characterisation of blue light photoreceptor gene family and their expression in tomato (Solanum lycopersicum) under cold stress.
The Arabidopsis thaliana L. photoreceptor genes homologues in tomato (Solanum lycopersicum L.) genome were analysed using bioinformatic tools. The expression pattern of these genes under cold stress was also evaluated. Transcriptome analysis of the tomato sequence revealed that the photoreceptor gene family is involved in abiotic stress tolerance. They participate in various pathways and controlling multiple metabolic processes. They are structurally related to PAS, LIGHT-OXYGEN-VOLTAGE-SENSING (LOV), DNA photolyase, 5,10-methenyl tetrahydrofolate (MTHF), flavin-binding kelch F-box, GAF, PHY, Seven-bladed beta-propeller and C27 domains. They also interact with flavin adenine dinucleotide (FAD), (5S)-5-methyl-2-(methylsulfanyl)-5-phenyl-3-(phenylamino)-3,5-dihydro-4H-imidazol -4-one (FNM) and Phytochromobilin (PvarphiB) ligands. These interactions help to create a cascade of protein phosphorylation involving in cell defence transcription or stress-regulated genes. They localisation of these gene families on tomato chromosomes appeared to be uneven. Phylogenetic tree of tomato and Arabidopsis photoreceptor gene family were classified into eight subgroups, indicating gene expression diversity. Morphological and physiological assessment revealed no dead plant after 4h of cold treatment. All the plants were found to be alive, but there were some variations in the data across different parameters. Cold stress significantly reduced the rate of photosynthesis from 10.06 to 3.16mumolm-2 s-1, transpiration from 4.6 to 1.3mmolm-2 s-1, and stomatal conductance from 94.6 to 25.6mmolm-2 s-1. The cold stressed plants also had reduced height, root/shoot length, and fresh/dry biomass weight than the control plants. Relative expression analysis under cold stress revealed that after 4h, light stimulates the transcript level of Cry2 from 1.9 to 5.7 and PhyB from 0.98 to 6.9 compared to other photoreceptor genes.
PMID: 35437142
Funct Plant Biol , IF:3.101 , 2022 Apr doi: 10.1071/FP21230
Meta-analysis of transcriptomic responses to cold stress in plants.
Transcriptomic analyses are needful tools to gain insight into the molecular mechanisms underlying plant responses to abiotic stresses. The aim of this study was to identify key genes differentially regulated in response to chilling stress in various plant species with different levels of tolerance to low temperatures. A meta-analysis was performed using the RNA-Seq data of published studies whose experimental conditions were comparable. The results confirmed the importance of ethylene in the hormonal cross-talk modulating the defensive responses against chilling stress, especially in sensitive species. The transcriptomic activity of five Ethylene Response Factors genes and a REDOX Responsive Transcription Factor 1 involved in hormone-related pathways belonging to ethylene metabolism and signal transduction were induced. Transcription activity of two genes encoding for heat shock factors was enhanced, together with various genes associated with developmental processes. Several transcription factor families showed to be commonly induced between different plant species. Protein-protein interaction networks highlighted the role of the photosystems I and II, as well as genes encoding for HSF and WRKY transcription factors. A model of gene regulatory network underlying plant responses to chilling stress was developed, allowing the delivery of new candidate genes for genetic improvement of crops towards low temperatures tolerance.
PMID: 35379384
PeerJ , IF:2.984 , 2022 , V10 : Pe13273 doi: 10.7717/peerj.13273
Genome-wide identification of the SWEET gene family mediating the cold stress response in Prunus mume.
Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, School of Landscape Architecture, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, Beijing Forestry University, Beijing, China.
The Sugars Will Eventually be Exported Transporter (SWEET) gene family encodes a family of sugar transporters that play essential roles in plant growth, reproduction, and biotic and abiotic stresses. Prunus mume is a considerable ornamental wood plant with high edible and medicinal values; however, its lack of tolerance to low temperature has severely limited its geographical distribution. To investigate whether this gene family mediates the response of P. mume to cold stress, we identified that the P. mume gene family consists of 17 members and divided the family members into four groups. Sixteen of these genes were anchored on six chromosomes, and one gene was anchored on the scaffold with four pairs of segmental gene duplications and two pairs of tandem gene duplications. Cis-acting regulatory element analysis indicated that the PmSWEET genes are potentially involved in P. mume development, including potentially regulating roles in procedure, such as circadian control, abscisic acid-response and light-response, and responses to numerous stresses, such as low-temperature and drought. We performed low-temperature treatment in the cold-tolerant cultivar 'Songchun' and cold-sensitive cultivar 'Zaolve' and found that the expression of four of 17 PmSWEETs was either upregulated or downregulated with prolonged treatment times. This finding indicates that these family members may potentially play a role in cold stress responses in P. mume. Our study provides a basis for further investigation of the role of SWEET proteins in the development of P. mume and its responses to cold stress.
PMID: 35529486
Transgenic Res , IF:2.788 , 2022 Jun , V31 (3) : P381-389 doi: 10.1007/s11248-022-00307-9
MsSAMS, a cold stress-responsive gene, provides resistance to environmental stress in T2-generation transgenic plants.
Department of Bio-Resource Sciences, Kangwon National University, Chuncheon, 24341, Republic of Korea.; Interdisciplinary Program in Smart Science, Kangwon National University, Chuncheon, 2434, Republic of Korea.; Division of Bioresource Sciences, Kangwon National University, Chuncheon, 24341, South Korea. esseong@kangwon.ac.kr.
The SAMS (S-adenosylmethionine synthetase) gene is known to play an important role in the mechanism of cold resistance, as overexpression of this gene results in phenotypic changes in T1-generation transgenic plants. Accordingly, this study was conducted to test the expression of the MsSAMS gene in T2-generation transgenic plants and to investigate the resistance of these plants and the function of the transgene in response to various environmental stresses. For the morphological analysis of T2-generation transgenic plants overexpressing the MsSAMS gene, observations using scanning electron microscopy (SEM) were performed. T2-generation transgenic plants were obtained by planting a total of 5 lines, and their characteristics were tested by comparisons with those of the control. SEM revealed that the thickest leaves were produced by the T6 transgenic line-161.24 +/- 8.05 microm. The number of stomata ranged from 20.00 +/- 2.65 to 34.00 +/- 1.00 in the T2-generation transgenic plants, but the control had more stomata. Resistance to various factors, such as low temperature, drought, and oxidative stress, in the T2-generation transgenic plants was also confirmed. Under cold-stress conditions, the T6 transgenic line presented the lowest value (22.73%) of ion leakage, and under drought-stress conditions, compared with the control, the transgenic lines presented lower ion leakage after being treated with various concentrations of mannitol. Even under oxidative-stress conditions, the T2-generation transgenic plants presented ion leakage levels that were 32.91 +/- 4.24 to 48.33 +/- 3.54% lower than those of the control after treatment with various concentrations of methyl viologen. Regarding SAMS enzyme activity, as the duration of cold treatment increased, the activity in the transgenic plants tended to decrease and then increase. During 48 h of cold treatment, the control showed a decrease in SAM content, while the T2-generation transgenic plants presented an increase in SAM content, from 13.58 +/- 1.04 to 22.75 +/- 1.95 mg protein/g FW. The results suggest that the MsSAMS gene may be important to the mechanisms of resistance to oxidative and drought stresses in addition to its previously known association with cold resistance. Based on these results, it was suggested that the MsSAMS gene, whose expression is induced by cold stress, can serve as a marker of various responses to environmental stresses, because resistance to cold damage and various environmental stresses are stably inherited in the T2 generation.
PMID: 35461371
J Microbiol Biotechnol , IF:2.351 , 2022 Apr , V32 (5) : P1-12 doi: 10.4014/jmb.2201.01025
Exogenous Bio-Based 2,3-Butanediols Enhanced Abiotic Stress Tolerance of Tomato and Turfgrass Under Drought or Chilling Stress.
Department of Agricultural Chemistry, Institute of Environmentally Friendly Agriculture, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186, Republic of Korea.; Plant Healthcare Research Institute, JAN153 Biotech Incorporated, Gwangju 61186, Republic of Korea.; Research and Development Center, GS Caltex Corporation, Daejeon 34122, Republic of Korea.
Among abiotic stresses in plants, drought and chilling stresses reduce the supply of moisture to plant tissues, inhibit photosynthesis, and severely reduce plant growth and yield. Thus, the application of water stress-tolerant agents can be a useful strategy to maintain plant growth under abiotic stresses. This study assessed the effect of exogenous bio-based 2,3-butanediol (BDO) application on drought and chilling response in tomato and turfgrass, and expression levels of several plant signaling pathway-related gene transcripts. Bio-based 2,3-BDOs were formulated to levo-2,3-BDO 0.9% soluble concentrate (levo 0.9% SL) and meso-2,3-BDO 9% SL (meso 9% SL). Under drought and chilling stress conditions, the application of levo 0.9% SL in creeping bentgrass and meso 9% SL in tomato plants significantly reduced the deleterious effects of abiotic stresses. Interestingly, pretreatment with levo-2,3-BDO in creeping bentgrass and meso-2,3-BDO in tomato plants enhanced JA and SA signaling pathway-related gene transcript expression levels in different ways. In addition, all tomato plants treated with acibenzolar-S-methyl (as a positive control) withered completely under chilling stress, whereas 2,3-BDO-treated tomato plants exhibited excellent cold tolerance. According to our findings, bio-based 2,3-BDO isomers as sustainable water stress-tolerant agents, levo- and meso-2,3-BDOs, could enhance tolerance to drought and/or chilling stresses in various plants through somewhat different molecular activities without any side effects.
PMID: 35484968
Vet Med Sci , IF:1.95 , 2022 Apr doi: 10.1002/vms3.804
Effect of sage (Salvia officinalis L.) extract in antioxidant status and intestinal morphology of pulmonary hypertensive chickens.
Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahrekord University, Shahrekord, Iran.; Department of Basic Sciences, Physiology Division, Faculty of Veterinary Medicine, Shahrekord, Iran.; Department of Animal Science, Faculty of Agriculture, Shahrekord University, Shahrekord, Iran.
OBJECTIVES: The effects of dietary sage on the growth performance, antioxidant status, intestinal mucosa morphology, and pulmonary hypertensive response were investigated in broiler chickens with pulmonary hypertension. METHODS: Chicks (Ross 308) were reared under cold stress for 35 days and treated with 0.05% vitamin C (positive control) and 0 (control), 0.1 or 0.2% sage extracts, then performance, oxidant and antioxidant status, and intestinal morphology were evaluated. RESULTS: The index of pulmonary hypertension (RV:TV) was decreased, and weight gain (days 22-35) was increased in all treatments (except for sage 0.1%) compared with control (P < 0.05). Lipid peroxidation was decreased, whereas the activity of antioxidant enzymes (GPX, CAT, and SOD) was increased in the sage 0.2% group compared with control (P < 0.05). In the lung, SOD, CAT, and GPX transcripts were decreased in the sage 0.2% group compared with control (P < 0.05). In the right ventricle of the heart, SOD and CAT transcripts were increased in the sage 0.2% group compared with other groups of chickens, whereas GPX transcript was decreased (P < 0.05). The jejunal villus length in the chickens fed sage was significantly lower than in control (P < 0.05). The ileal villus width, villus surface area, and lamina proporia thickness in the chickens fed sage (0.2%) were increased compared with control (P < 0.05). CONCLUSIONS: Dietary supplementation of sage (0.2%) could modulate pulmonary hypertensive response, improve antioxidant status (enzymatic activity), intestinal morphometry, and absorptive surface in the broiler chickens.
PMID: 35405032
Genes Genomics , IF:1.839 , 2022 May doi: 10.1007/s13258-022-01263-8
Identification of Saccharum CaM gene family and function characterization of ScCaM1 during cold and oxidant exposure in Pichia pastoris.
Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.; Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China. jlguo@fafu.edu.cn.
BACKGROUND: Calmodulin (CaM) plays an essential role in binding calcium ions and mediating the interpretation of Ca(2+) signals in plants under various stresses. However, the evolutionary relationship of CaM family proteins in Saccharum has not been elucidated. OBJECTIVE: To deduce and explore the evolution and function of Saccharum CaM family. METHODS: A total of 104 typical CaMs were obtained from Saccharum spontaneum and other 18 plant species. The molecular characteristics and evolution of those CaM proteins were analyzed. A typical CaM gene, ScCaM1, was subsequently cloned from sugarcane (Saccharum spp. hybrid). Its expression patterns in different tissues and under various abiotic stresses were assessed by quantitative real-time PCR. Then the green fluorescent protein was used to determine the subcellular localization of ScCaM1. Finally, the function of ScCaM1 was evaluated via heterologous yeast expression systems. RESULTS: Three typical CaM members (SsCaM1, SsCaM2, and SsCaM3) were identified from the S. spontaneum genome database. CaMs were originated from the two last common ancestors before the origin of angiosperms. The number of CaM family members did not correlate to the genome size but correlated with allopolyploidization events. The ScCaM1 was more highly expressed in buds and roots than in other tissues. The expression patterns of ScCaM1 suggested that it was involved in responses to various abiotic stresses in sugarcane via different hormonal signaling pathways. Noteworthily, its expression levels appeared relatively stable during the cold exposure in the cold-tolerant variety but significantly suppressed in the cold-susceptible variety. Moreover, the recombinant yeast (Pichia pastoris) overexpressing ScCaM1 grew better than the wild-type yeast strain under cold and oxidative stresses. It was revealed that the ScCaM1 played a positive role in reactive oxygen species scavenging and conferred enhanced cold and oxidative stress tolerance to cells. CONCLUSION: This study provided comprehensive information on the CaM gene family in Saccharum and would facilitate further investigation of their functional characterization.
PMID: 35608775
J Microsc , IF:1.758 , 2022 Jun , V286 (3) : P252-262 doi: 10.1111/jmi.13101
Visualising the effect of freezing on the vascular system of wheat in three dimensions by in-block imaging of dye-infiltrated plants.
United States Department of Agriculture, Agricultural Research Service, Raleigh, North Carolina, USA.; Department of Crop and Soil Sciences, North Carolina State University, Raleigh, North Carolina, USA.
Infrared thermography has shown after roots of grasses freeze, ice spreads into the crown and then acropetally into leaves initially through vascular bundles. Leaves freeze singly with the oldest leaves freezing first and the youngest freezing later. Visualising the vascular system in its native 3-dimensional state will help in the understanding of this freezing process. A 2 cm section of the crown that had been infiltrated with aniline blue was embedded in paraffin and sectioned with a microtome. A photograph of the surface of the tissue in the paraffin block was taken after the microtome blade removed each 20 mum section. Two hundred to 300 images were imported into Adobe After Effects and a 3D volume of the region infiltrated by aniline blue dye was constructed. The reconstruction revealed that roots fed into what is functionally a region inside the crown that could act as a reservoir from which all the leaves are able to draw water. When a single root was fed dye solution, the entire region filled with dye and the vascular bundles of every leaf took up the dye; this indicated that the vascular system of roots was not paired with individual leaves. Fluorescence microscopy suggested the edge of the reservoir might be composed of phenolic compounds. When plants were frozen, the edges of the reservoir became leaky and dye solution spread into the mesophyll outside the reservoir. The significance of this change with regard to freezing tolerance is not known at this time. Thermal cameras that allow visualisation of water freezing in plants have shown that in crops like wheat, oats and barley, ice forms first at the bottom of the plant and then moves upwards into leaves through water conducting channels. Leaves freeze one at a time with the oldest leaves freezing first and then younger ones further up the stem freeze later. To better understand why plants freeze like this, we reconstructed a 3-dimensional view of the water conducting channels. After placing the roots of a wheat plant in a blue dye and allowing it to pull the dye upwards into leaves, we took a part of the stem just above the roots and embedded it in paraffin. We used a microtome to slice a thin layer of the paraffin containing the plant and then photographed the surface after each layer was removed. After taking about 300 images, we used Adobe After Effects software to re-construct the plant with the water conducting system in three dimensions. The 3D reconstruction showed that roots fed into a roughly spherical area at the bottom of the stem that could act as a kind of tank or reservoir from which the leaves pull up water. When we put just one root in dye, the entire reservoir filled up and the water conducting channels in every leaf took up the dye. This indicates that the water channels in roots were not directly connected to specific leaves as we had thought. When plants were frozen, the dye leaked out of the reservoir and spread into cells outside. Research is continuing to understand the significance of this change during freezing. It is possible that information about this effect can be used to help breeders develop more winter-hardy crop plants.
PMID: 35319110