Dev Cell , IF:12.27 , 2022 Aug , V57 (15) : P1883-1898.e5 doi: 10.1016/j.devcel.2022.06.012
Sulfenylation of ENOLASE2 facilitates H2O2-conferred freezing tolerance in Arabidopsis.
State Key Laboratory of Crop Stress Adaptation and Improvement, State Key Laboratory of Cotton Biology, School of Life Sciences, Key Laboratory of Plant Stress Biology, College of Agriculture, Henan University, Kaifeng 475004, China. Electronic address: liuwencheng@henu.edu.cn.; Key Laboratory of Biotechnology of Salt Tolerant Crops of Hainan Province, Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources (Provincial Ministry Building State Key Laboratory Breeding Base), College of Tropical Crops, Hainan University, Haikou, Hainan 570228, China.; Key Laboratory of Biotechnology of Salt Tolerant Crops of Hainan Province, Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources (Provincial Ministry Building State Key Laboratory Breeding Base), College of Tropical Crops, Hainan University, Haikou, Hainan 570228, China; Sanya Nanfan Research Institute of Hainan University, Hainan Yazhou Bay Seed Laboratory, Sanya, Hainan 572025, China.; State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan 430072, China.; Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening, Jiangsu Ocean University, Lianyungang 222005, China.; State Key Laboratory of Crop Stress Adaptation and Improvement, State Key Laboratory of Cotton Biology, School of Life Sciences, Key Laboratory of Plant Stress Biology, College of Agriculture, Henan University, Kaifeng 475004, China.; Key Laboratory of Biotechnology of Salt Tolerant Crops of Hainan Province, Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources (Provincial Ministry Building State Key Laboratory Breeding Base), College of Tropical Crops, Hainan University, Haikou, Hainan 570228, China; Sanya Nanfan Research Institute of Hainan University, Hainan Yazhou Bay Seed Laboratory, Sanya, Hainan 572025, China. Electronic address: yuanhongmei@hainanu.edu.cn.
H2O2 affects the expression of genes that are involved in plant responses to diverse environmental stresses; however, the underlying mechanisms remain elusive. Here, we demonstrate that H2O2 enhances plant freezing tolerance through its effect on a protein product of low expression of osmotically responsive genes2 (LOS2). LOS2 is translated into a major product, cytosolic enolase2 (ENO2), and sometimes an alternative product, the transcription repressor c-Myc-binding protein (MBP-1). ENO2, but not MBP-1, promotes cold tolerance by binding the promoter of C-repeat/DRE binding factor1 (CBF1), a central transcription factor in plant cold signaling, thus activating its expression. Overexpression of CBF1 restores freezing sensitivity of a LOS2 loss-of-function mutant. Furthermore, cold-induced H2O2 increases nuclear import and transcriptional binding activity of ENO2 by sulfenylating cysteine 408 and thereby promotes its oligomerization. Collectively, our results illustrate how H2O2 activates plant cold responses by sulfenylating ENO2 and promoting its oligomerization, leading to enhanced nuclear translocation and transcriptional activation of CBF1.
PMID: 35809562
Plant Cell , IF:11.277 , 2022 Aug doi: 10.1093/plcell/koac253
WRKY53 negatively regulates rice cold tolerance at the booting stage by fine-tuning anther gibberellin levels.
Northeast Institute of Geography and Agroecology, Key Laboratory of Soybean Molecular Design Breeding, Chinese Academy of Sciences, Harbin 150081, China.; University of Chinese Academy of Sciences, Beijing 100049, China.; State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing 210095, China.; Key Laboratory of Saline-alkali Vegetation Ecology Restoration (Northeast Forestry University), Ministry of Education, Harbin 150040, China.; College of Life Science, Northeast Forestry University, Harbin 150040, China.; The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China.
Cold tolerance at the booting stage (CTB) is a major factor limiting rice (Oryza sativa L.) productivity and geographical distribution. A few cold-tolerance genes have been identified, but they either need to be overexpressed to result in CTB or cause yield penalties, limiting their utility for breeding. Here, we characterize the function of the cold-induced transcription factor WRKY53 in rice. The wrky53 mutant displays increased CTB, as determined by higher seed setting. Low temperature is associated with lower gibberellin (GA) contents in anthers in the wild type but not in the wrky53 mutant, which accumulates slightly more GA in its anthers. WRKY53 directly binds to the promoters of GA biosynthesis genes and transcriptionally represses them in anthers. In addition, we uncover a possible mechanism by which GA regulates male fertility: SLENDER RICE1 (SLR1) interacts with and sequesters two critical transcription factors for tapetum development, UNDEVELOPED TAPETUM1 (UDT1) and TAPETUM DEGENERATION RETARDATION (TDR), and GA alleviates the sequestration by SLR1, thus allowing UDT1 and TDR to activate transcription. Finally, knocking out WRKY53 in diverse varieties increases cold tolerance without a yield penalty, leading to a higher yield in rice subjected to cold stress. Together, these findings provide a target for improving CTB in rice.
PMID: 35972376
Plant Cell , IF:11.277 , 2022 Jul , V34 (8) : P2833-2851 doi: 10.1093/plcell/koac137
The transcription factor bZIP68 negatively regulates cold tolerance in maize.
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 uncovers an evolutionary cis-regulatory variant that could be used to improve cold tolerance in maize.
PMID: 35543494
Cell Discov , IF:10.849 , 2022 Jul , V8 (1) : P71 doi: 10.1038/s41421-022-00413-2
Chilling-induced phosphorylation of IPA1 by OsSAPK6 activates chilling tolerance responses in rice.
State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, China.; University of Chinese Academy of Sciences, Beijing, China.; State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, China.; State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, China. hyu@genetics.ac.cn.; University of Chinese Academy of Sciences, Beijing, China. hyu@genetics.ac.cn.
Chilling is a major abiotic stress harming rice development and productivity. The C-REPEAT BINDING FACTOR (CBF)-dependent transcriptional regulatory pathway plays a central role in cold stress and acclimation in Arabidopsis. In rice, several genes have been reported in conferring chilling tolerance, however, the chilling signaling in rice remains largely unknown. Here, we report the chilling-induced OSMOTIC STRESS/ABA-ACTIVATED PROTEIN KINASE 6 (OsSAPK6)-IDEAL PLANT ARCHITECTURE 1 (IPA1)-OsCBF3 signal pathway in rice. Under chilling stress, OsSAPK6 could phosphorylate IPA1 and increase its stability. In turn, IPA1 could directly bind to the GTAC motif on the OsCBF3 promoter to elevate its expression. Genetic evidence showed that OsSAPK6, IPA1 and OsCBF3 were all positive regulators of rice chilling tolerance. The function of OsSAPK6 in chilling tolerance depended on IPA1, and overexpression of OsCBF3 could rescue the chilling-sensitive phenotype of ipa1 loss-of-function mutant. Moreover, the natural gain-of-function allele ipa1-2D could simultaneously enhance seedling chilling tolerance and increase grain yield. Taken together, our results revealed a chilling-induced OsSAPK6-IPA1-OsCBF signal cascade in rice, which shed new lights on chilling stress-tolerant rice breeding.
PMID: 35882853
New Phytol , IF:10.151 , 2022 Jul doi: 10.1111/nph.18403
A single-nucleotide polymorphism in WRKY33 promoter is associated with the cold sensitivity in cultivated tomato.
Department of Horticulture, Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Yuhangtang Road 866, Hangzhou, 310058, China.; Hainan Institute, Zhejiang University, Sanya, 572000, China.; Agricultural Experiment Station, Zhejiang University, Hangzhou, 310058, China.; Department of Agricultural Sciences Biotechnology and Food Science, Cyprus University of Technology, Lemesos, 999058, Cyprus.; Key Laboratory of Horticultural Plants Growth, Development and Quality Improvement, Agricultural Ministry of China, Yuhangtang Road 866, Hangzhou, 310058, China.; Shandong (Linyi) Institute of Modern Agriculture, Zhejiang University, Linyi, 276000, China.
Natural variations in cis-regulatory regions often affect crop phenotypes by altering gene expression. However, the mechanism of how promoter mutations affect gene expression and crop stress tolerance is still poorly understood. In this study, by analyzing RNA-sequencing (RNA-Seq) data and reverse transcription quantitative real-time PCR validation in the cultivated tomato and its wild relatives, we reveal that the transcripts of WRKY33 are almost unchanged in cold-sensitive cultivated tomato Solanum lycopersicum L. 'Ailsa Craig' but are significantly induced in cold-tolerant wild tomato relatives Solanum habrochaites LA1777 and Solanum pennellii LA0716 under cold stress. Overexpression of SlWRKY33 or ShWRKY33 positively regulates cold tolerance in tomato. Variant of the critical W-box in SlWRKY33 promoter results in the loss of self-transcription function of SlWRKY33 under cold stress. Analysis integrating RNA-Seq and chromatin immunoprecipitation sequencing data reveals that SlWRKY33 directly targets and induces multiple kinases, transcription factors, and molecular chaperone genes, such as CDPK11, MYBS3, and BAG6, thus enhancing cold tolerance. In addition, heat- and Botrytis-induced WRKY33s expression in both wild and cultivated tomatoes are independent of the critical W-box variation. Our findings suggest nucleotide polymorphism in cis-regulatory regions is crucial for different cold sensitivity between cultivated and wild tomato plants.
PMID: 35892173
New Phytol , IF:10.151 , 2022 Sep , V235 (6) : P2331-2349 doi: 10.1111/nph.18304
Two AT-Hook proteins regulate A/NINV7 expression to modulate sucrose catabolism for cold tolerance in Poncirus trifoliata.
Key Laboratory of Horticultural Plant Biology (MOE), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan, 430070, China.; Department of Horticulture, Faculty of Agriculture, Tishreen University, Lattakia, Syria.; Hubei Hongshan Laboratory, Wuhan, 430070, China.
Invertase (INV)-mediated sucrose (Suc) hydrolysis, leading to the irreversible production of glucose (Glc) and fructose (Frc), plays an essential role in abiotic stress tolerance of plants. However, the regulatory network associated with the Suc catabolism in response to cold environment remains largely elusive. Herein, the cold-induced alkaline/neutral INV gene PtrA/NINV7 of trifoliate orange (Poncirus trifoliata (L.) Raf.) was shown to function in cold tolerance via mediating the Suc hydrolysis. Meanwhile, a nuclear matrix-associated region containing A/T-rich sequences within its promoter was indispensable for the cold induction of PtrA/NINV7. Two AT-Hook Motif Containing Nuclear Localized (AHL) proteins, PtrAHL14 and PtrAHL17, were identified as upstream transcriptional activators of PtrA/NINV7 by interacting with the A/T-rich motifs. PtrAHL14 and PtrAHL17 function positively in the cold tolerance by modulating PtrA/NINV7-mediated Suc catabolism. Furthermore, both PtrAHL14 and PtrAHL17 could form homo- and heterodimers between each other, and interacted with two histone acetyltransferases (HATs), GCN5 and TAF1, leading to elevated histone3 acetylation level under the cold stress. Taken together, our findings unraveled a new cold-responsive signaling module (AHL14/17-HATs-A/NINV7) for orchestration of Suc catabolism and cold tolerance, which shed light on the molecular mechanisms underlying Suc catabolism catalyzed by A/NINVs under cold stress.
PMID: 35695205
Crit Rev Biotechnol , IF:8.429 , 2022 Jul : P1-18 doi: 10.1080/07388551.2022.2053056
Cold stress regulates accumulation of flavonoids and terpenoids in plants by phytohormone, transcription process, functional enzyme, and epigenetics.
Wenzhou Safety (Emergency) Institute of Tianjin University, Wenzhou, China.; School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, China.; Tianjin Pharmaceutical Research Institute, Tianjin, China.; National Resource Center for Chinese Meteria Medica, China Academy of Chinese Medical Sciences, Beijing, China.
Plants make different defense mechanisms in response to different environmental stresses. One common way is to produce secondary metabolites. Temperature is the main environmental factor that regulates plant secondary metabolites, especially flavonoids and terpenoids. Stress caused by temperature decreasing to 4-10 degrees C is conducive to the accumulation of flavonoids and terpenoids. However, the accumulation mechanism under cold stress still lacks a systematic explanation. In this review, we summarize three aspects of cold stress promoting the accumulation of flavonoids and terpenoids in plants, that is, by affecting (1) the content of endogenous plant hormones, especially jasmonic acid and abscisic acid; (2) the expression level and activity of important transcription factors, such as bHLH and MYB families. This aspect also includes post-translational modification of transcription factors caused by cold stress; (3) key enzyme genes expression and activity in the biosynthesis pathway, in addition, the rate-limiting enzyme and glycosyltransferases genes are responsive to cold stress. The systematic understanding of cold stress regulates flavonoids, and terpenoids will contribute to the future research of genetic engineering breeding, metabolism regulation, glycosyltransferases mining, and plant synthetic biology.
PMID: 35848841
Plant Physiol , IF:8.34 , 2022 Aug , V189 (4) : P2500-2516 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 knock down (KD) reduced cold tolerance. Furthermore, an APETALA2/ethylene-responsive factor (ERF) 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 KD 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-sequencing and targeted metabolomics assays, we found that OsERF096 modified hormone content and signaling pathways. Finally, phenotypic and reverse transcription-quantitative PCR assays showed that jasmonic acid (JA) methyl ester application recovered the cold-sensitive phenotype and JA-activated expression of three 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 Aug , V189 (4) : P2044-2060 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 210095, 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 MYB binding site (MBS) motif that was essential for the response of MdSIZ1 to low temperature (LT) 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 LT 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
Food Chem , IF:7.514 , 2022 Aug , V386 : P132720 doi: 10.1016/j.foodchem.2022.132720
Characterization of honey peach (Prunus persica (L.) Batsch) aroma variation and unraveling the potential aroma metabolism mechanism through proteomics analysis under abiotic stress.
Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China.; Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; Enshi Tujia and Miao Autonomous Prefecture Academy of Agricultural Sciences, Hubei 445000, China.; Enshi Tujia and Miao Autonomous Prefecture Academy of Agricultural Sciences, Hubei 445000, China.; Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China. Electronic address: liyi01@caas.cn.; Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China. Electronic address: lijianxun@caas.cn.
Honey peach (Prunus persica (L.) Batsch) is a climacteric fruit with short storage period. Generally, the low temperature storage (LTS) technology is implemented to lessen aroma loss and keep the quality. However, the LTS procedure brings about cold stress issues and affects the aroma metabolism. It is essential to unravel the primary aroma and the corresponding metabolism mechanism through key proteins under abiotic stress. In this study, the primary components were characterized under LTS at 1 degrees C during 0 to 40 days. Furthermore, the proteomics analysis was performed to acquire differentially expressed proteins to clarify the underlying metabolism mechanisms of the primary aroma and potential proteins. As a result, four proteins were considered as potential key proteins that associated with fatty acid and amino acid metabolism under cold stress. Additionally, this study provides theoretical cornerstones for regulating and improving the quality of honey peach.
PMID: 35339764
Plant Cell Environ , IF:7.228 , 2022 Sep , V45 (9) : P2762-2779 doi: 10.1111/pce.14386
Modulation of plant development and chilling stress responses by alternative splicing events under control of the spliceosome protein SmEb in Arabidopsis.
School of Life Sciences, Anhui Agricultural University, Hefei, Anhui, China.; Shanghai Center for Plant Stress Biology and Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, China.; University of Chinese Academy of Sciences, Shanghai, China.; Department of Plant Science and Landscape Architecture, University of Maryland, College Park, Maryland, USA.; State Key Laboratory of Crop Stress Biology for Arid Areas and College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China.
Cold stress resulting from chilling and freezing temperatures substantially inhibits plant growth and reduces crop production worldwide. Tremendous research efforts have been focused on elucidating the molecular mechanisms of freezing tolerance in plants. However, little is known about the molecular nature of chilling stress responses in plants. Here we found that two allelic mutants in a spliceosome component gene SmEb (smeb-1 and smeb-2) are defective in development and responses to chilling stress. RNA-seq analysis revealed that SmEb controls the splicing of many pre-messenger RNAs (mRNAs) under chilling stress. Our results suggest that SmEb is important to maintain proper ratio of the two COP1 splicing variants (COP1a/COP1b) to fine tune the level of HY5. In addition, the transcription factor BES1 shows a dramatic defect in pre-mRNA splicing in the smeb mutants. Ectopic expression of the two BES1 splicing variants enhances the chilling sensitivity of the smeb-1 mutant. Furthermore, biochemical and genetic analysis showed that CBFs act as negative upstream regulators of SmEb by directly suppressing its transcription. Together, our results demonstrate that proper alternative splicing of pre-mRNAs controlled by the spliceosome component SmEb is critical for plant development and chilling stress responses.
PMID: 35770732
J Exp Bot , IF:6.992 , 2022 Aug , V73 (14) : P4981-4995 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, Australia.; 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), as the difference in flowering time between irrigated and rainfed crops, and use FST genome scanning to probe for genomic regions under selection for this trait in chickpea (Cicer arietinum). Owing to the negligible variation in daylength in our dataset, 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, as quantified with carbon isotope composition. Genomic regions on chromosomes 4-8 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 that DEP reduces the likelihood of drought and heat stress at the expense of increased likelihood of cold stress. Accounting for DEP would improve genetic and phenotypic models of phenology.
PMID: 35526198
Cells , IF:6.6 , 2022 Jul , V11 (15) doi: 10.3390/cells11152316
HSP70 Gene Family in Brassica rapa: Genome-Wide Identification, Characterization, and Expression Patterns in Response to Heat and Cold Stress.
State Key Laboratory of North China Crop Improvement and Regulation, Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, College of Horticulture, Hebei Agricultural University, Baoding 071000, China.
Heat shock proteins protect plants from abiotic stress, such as salt, drought, heat, and cold stress. HSP70 is one of the major members of the heat shock protein family. To explore the mechanism of HSP70 in Brassica rapa, we identified 28 putative HSP70 gene family members using state-of-the-art bioinformatics-based tools and methods. Based on chromosomal mapping, HSP70 genes were the most differentially distributed on chromosome A03 and the least distributed on chromosome A05. Ka/Ks analysis revealed that B. rapa evolution was subjected to intense purifying selection of the HSP70 gene family. RNA-sequencing data and expression profiling showed that heat and cold stress induced HSP70 genes. The qRT-PCR results verified that the HSP70 genes in Chinese cabbage (Brassica rapa ssp. pekinensis) are stress-inducible under both cold and heat stress. The upregulated expression pattern of these genes indicated the potential of HSP70 to mitigate environmental stress. These findings further explain the molecular mechanism underlying the responses of HSP70 to heat and cold stress.
PMID: 35954158
Plant J , IF:6.417 , 2022 Aug doi: 10.1111/tpj.15950
The OsWRKY63-OsWRKY76-OsDREB1B module regulates chilling tolerance in rice.
Jilin Province Engineering Laboratory of Plant Genetic Improvement, College of Plant Science, Jilin University, Changchun, China.
Rice (Oryza sativa) is sensitive to low temperatures, which affects the yield and quality of rice. Therefore, uncovering the molecular mechanisms behind chilling tolerance is a critical task for improving cold tolerance in rice cultivars. Here, we report that OsWRKY63, a WRKY transcription factor with an unknown function, negatively regulates chilling tolerance in rice. OsWRKY63-overexpressing lines rendered rice more sensitive to cold stress. Conversely, using a CRISPR/Cas9 genome editing approach, OsWRKY63-knockout mutants led to increased chilling tolerance. OsWRKY63 was expressed in all rice tissues and was induced under cold stress, dehydration stress, high salinity stress, and ABA treatment. OsWRKY63 localized in the nucleus plays a role as a transcription repressor and downregulates many cold stress-related genes and reactive oxygen species scavenging-related genes. Molecular, biochemical, and genetic assays showed that OsWRKY76 is a direct target gene of OsWRKY63 and that its expression was suppressed by OsWRKY63. OsWRKY76-knockout lines had dramatically decreased cold tolerance, and they repressed the cold-induced expression of five OsDREB1 genes. OsWRKY76 interacted with OsbHLH148, transactivating the expression of OsDREB1B to enhance chilling tolerance in rice. Thus, our study suggests that OsWRKY63 negatively regulates chilling tolerance in a model of the OsWRKY63-OsWRKY76-OsDREB1B transcriptional regulatory cascade in rice.
PMID: 35996876
Plant J , IF:6.417 , 2022 Aug , V111 (4) : P1052-1068 doi: 10.1111/tpj.15872
mRNA N(6) -methyladenosine is critical for cold tolerance in Arabidopsis.
Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, 74078, USA.; Department of Biology, University of Pennsylvania, Philadelphia, PA, 19104, USA.; Dale Bumpers National Rice Research Center, United States Department of Agriculture-Agricultural Research Services, Stuttgart, AR, 72160, USA.
Plants respond to low temperatures by altering the mRNA abundance of thousands of genes contributing to numerous physiological and metabolic processes that allow them to adapt. At the post-transcriptional level, these cold stress-responsive transcripts undergo alternative splicing, microRNA-mediated regulation and alternative polyadenylation, amongst others. Recently, m(6) A, m(5) C and other mRNA modifications that can affect the regulation and stability of RNA were discovered, thus revealing another layer of post-transcriptional regulation that plays an important role in modulating gene expression. The importance of m(6) A in plant growth and development has been appreciated, although its significance under stress conditions is still underexplored. To assess the role of m(6) A modifications during cold stress responses, methylated RNA immunoprecipitation sequencing was performed in Arabidopsis seedlings esposed to low temperature stress (4 degrees C) for 24 h. This transcriptome-wide m(6) A analysis revealed large-scale shifts in this modification in response to low temperature stress. Because m(6) A is known to affect transcript stability/degradation and translation, we investigated these possibilities. Interestingly, we found that cold-enriched m(6) A-containing transcripts demonstrated the largest increases in transcript abundance coupled with increased ribosome occupancy under cold stress. The significance of the m(6) A epitranscriptome on plant cold tolerance was further assessed using the mta mutant in which the major m(6) A methyltransferase gene was mutated. Compared to the wild-type, along with the differences in CBFs and COR gene expression levels, the mta mutant exhibited hypersensitivity to cold treatment as determined by primary root growth, biomass, and reactive oxygen species accumulation. Furthermore, and most importantly, both non-acclimated and cold-acclimated mta mutant demonstrated hypersensitivity to freezing tolerance. Taken together, these findings suggest a critical role for the epitranscriptome in cold tolerance of Arabidopsis.
PMID: 35710867
Plant J , IF:6.417 , 2022 Aug , V111 (4) : P1032-1051 doi: 10.1111/tpj.15870
Cold-adaptive evolution at the reproductive stage in Geng/japonica subspecies reveals the role of OsMAPK3 and OsLEA9.
State Key Laboratory of Agrobiotechnology/Beijing Key Laboratory of Crop Genetic Improvement, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China.
Cold stress at the reproductive stage severely affects the production and geographic distribution of rice. The Geng/japonica subpopulation gradually developed stronger cold adaptation than the Xian/indica subpopulation during the long-term domestication of cultivated rice. However, the evolutionary path and natural alleles underlying the cold adaptability of intra-Geng subspecies remain largely unknown. Here, we identified MITOGEN-ACTIVATED PROTEIN KINASE 3 (OsMAPK3) and LATE EMBRYOGENESIS ABUNDANT PROTEIN 9 (OsLEA9) as two important regulators for the cold adaptation of Geng subspecies from a combination of transcriptome analysis and genome-wide association study. Transgenic validation showed that OsMAPK3 and OsLEA9 confer cold tolerance at the reproductive stage. Selection and evolution analysis suggested that the Geng version of OsMAPK3 (OsMAPK3(Geng) ) directly evolved from Chinese Oryza rufipogon III and was largely retained in high-latitude and high-altitude regions with low temperatures during domestication. Later, the functional nucleotide polymorphism (FNP-776) in the Kunmingxiaobaigu and Lijiangxiaoheigu version of the OsLEA9 (OsLEA9(KL) ) promoter originated from novel variation of intra-Geng was selected and predominantly retained in temperate Geng to improve the adaptation of Geng together with OsMAPK3(Geng) to colder climatic conditions in high-latitude areas. Breeding potential analysis suggested that pyramiding of OsMAPK3(Geng) and OsLEA9(KL) enhanced the cold tolerance of Geng and promotes the expansion of cultivated rice to colder regions. This study not only highlights the evolutionary path taken by the cold-adaptive differentiation of intra-Geng, but also provides new genetic resources for rice molecular breeding in low-temperature areas.
PMID: 35706359
Plant J , IF:6.417 , 2022 Aug doi: 10.1111/tpj.15944
Temperature regulation of CAMTA3 gene induction activity is mediated through the DNA binding domain.
MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, 48824, USA.; MSU Plant Resilience Institute, Michigan State University, East Lansing, MI, 48824, USA.; Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, 48824, USA.
The Calmodulin-binding Transcription Activator (CAMTA) proteins of Arabidopsis thaliana have a major role in cold acclimation contributing to rapid induction of CBF and other genes that impart freezing tolerance in plants exposed to cold temperature (4 degrees C). The goal of this study was to better understand how the gene induction activity of CAMTA3 is regulated by temperature. Our results indicate that a severely truncated version of CAMTA3, CAMTA3(334) , which includes the N-terminal CG-1 DNA binding domain and a newly identified transcriptional activation domain (TAD), was able to rapidly induce expression of CBF2 and two newly identified target genes, EXPL1 and NCED3, in response to cold temperature. Additionally, CAMTA3(334) was able to restore freezing tolerance when expressed in a camta23 double mutant. The ability of CAMTA3 and CAMTA3(334) to induce target genes at cold temperature did not involve increased levels of these proteins or increased binding of these proteins to target gene promoters in cold-treated plants. Rather, domain swapping experiments indicated that the CAMTA3 CG-1 domain conferred temperature-dependence on the ability of the CAMTA3 TAD to induce gene expression. The CG-1 domain also enabled the TAD to induce expression of target genes at moderate temperature (22 degrees C) in response to cycloheximide treatment consistent with the TAD activity not being intrinsically temperature-dependent. We propose a working model in which temperature regulation of CAMTA3 gene induction activity occurs independently from the C-terminal calmodulin-binding domains which previously had been proposed to activate CAMTA3 transcriptional activity in response to cold temperature.
PMID: 35960653
Mol Ecol , IF:6.185 , 2022 Aug doi: 10.1111/mec.16666
Polygenic adaptation contributes to the invasive success of the Colorado potato beetle.
Key Laboratory of Zoological Systematics and Evolution Institute of Zoology, Chinese Academy of Sciences, Beijing, China.; Institute of Plant and Environmental Protection, Beijing Academy of Agriculture and Forestry Sciences, Beijing, China.; Department of Entomology and Wildlife Ecology, University of Delaware, Newark, Delaware, USA.; Institute for Evolution & Biodiversity, University of Munster, Hufferstr. 1, DE-48149, Munster, Germany.; Laboratory of Biological Plant Protection and Biotechnology, Novosibirsk State Agrarian University, 630039, Dobrolubova str. 160, Novosibirsk, Russia.
How invasive species cope with novel selective pressures with limited genetic variation is a fundamental question in molecular ecology. Several mechanisms have been proposed, but they can lack generality. Here, we addressed an alternative solution, polygenic adaptation, wherein traits that arise from multiple combinations of loci may be less sensitive to loss of variation during invasion. We tested the polygenic signal of environmental adaptation of Colorado potato beetle (CPB) introduced in Eurasia. Population genomic analyses showed declining genetic diversity in the eastward expansion of Eurasian populations, and weak population genetic structure (except for the invasion fronts in Asia). Demographic history showed that all populations shared a strong bottleneck about 100 years ago when CPB was introduced to Europe. Genome scans revealed a suite of genes involved in activity regulation functions that are plausibly related to cold stress, including some well-founded functions (e.g., the activity of phosphodiesterase, the G-protein regulator) and discrete functions. Such polygenic architecture supports the hypothesis that polygenic adaptation and potentially genetic redundancy can fuel the adaptation of CPB despite strong genetic depletion, thus representing a promising general mechanism for resolving the genetic paradox of invasion. More broadly, complex traits based on polygenes may be less sensitive to invasive bottlenecks, thus ensuring the evolutionary success of invasive species in novel environments.
PMID: 35984732
Int J Mol Sci , IF:5.923 , 2022 Aug , V23 (16) doi: 10.3390/ijms23169472
A Long Noncoding RNA Derived from lncRNA-mRNA Networks Modulates Seed Vigor.
National Engineering Research Center of Plant Space Breeding, South China Agricultural University, Guangzhou 510642, China.
The discovery of long noncoding RNAs (lncRNAs) has filled a great gap in our understanding of posttranscriptional gene regulation in a variety of biological processes related to plant stress responses. However, systematic analyses of the lncRNAs expressed in rice seeds that germinate under cold stress have been elusive. In this study, we performed strand-specific whole transcriptome sequencing in germinated rice seeds under cold stress and normal temperature. A total of 6258 putative lncRNAs were identified and expressed in a stage-specific manner compared to mRNA. By investigating the targets of differentially expressed (DE) lncRNAs of LT-I (phase I of low temperature)/NT-I (phase I of normal temperature), it was shown that the auxin-activated signaling pathway was significantly enriched, and twenty-three protein-coding genes with most of the members of the SAUR family located in chromosome 9 were identified as the candidate target genes that may interact with five lncRNAs. A seed vigor-related lncRNA, SVR, which interplays with the members of the SAUR gene family in cis was eventually identified. The CRISPR/Cas 9 engineered mutations in SVR cause delay of germination. The findings provided new insights into the connection between lncRNAs and the auxin-activated signaling pathway in the regulation of rice seed vigor.
PMID: 36012737
Int J Mol Sci , IF:5.923 , 2022 Aug , V23 (16) doi: 10.3390/ijms23169439
Overexpression of PgCBF3 and PgCBF7 Transcription Factors from Pomegranate Enhances Freezing Tolerance in Arabidopsis under the Promoter Activity Positively Regulated by PgICE1.
College of Horticulture, Henan Agricultural University, Zhengzhou 450002, China.
Cold stress limits plant growth, development and yields, and the C-repeat binding factors (CBFs) function in the cold resistance in plants. However, how pomegranate CBF transcription factors respond to cold signal remains unclear. Considering the significantly up-regulated expression of PgCBF3 and PgCBF7 in cold-tolerant Punica granatum 'Yudazi' in comparison with cold-sensitive 'Tunisia' under 4 degrees C, the present study focused on the two CBF genes. PgCBF3 was localized in the nucleus, while PgCBF7 was localized in the cell membrane, cytoplasm, and nucleus, both owning transcriptional activation activity in yeast. Yeast one-hybrid and dual-luciferase reporter assay further confirmed that PgICE1 could specifically bind to and significantly enhance the activation activity of the promoters of PgCBF3 and PgCBF7. Compared with the wild-type plants, the PgCBF3 and PgCBF7 transgenic Arabidopsis thaliana lines had the higher survival rate after cold treatment; exhibited increased the contents of soluble sugar and proline, while lower electrolyte leakage, malondialdehyde content, and reactive oxygen species production, accompanying with elevated enzyme activity of catalase, peroxidase, and superoxide dismutase; and upregulated the expression of AtCOR15A, AtCOR47, AtRD29A, and AtKIN1. Collectively, PgCBFs were positively regulated by the upstream PgICE1 and mediated the downstream COR genes expression, thereby enhancing freezing tolerance.
PMID: 36012703
Int J Mol Sci , IF:5.923 , 2022 Aug , V23 (16) doi: 10.3390/ijms23168914
Characterization of the SWEET Gene Family in Longan (Dimocarpus longan) and the Role of DlSWEET1 in Cold Tolerance.
Institute of Genetics and Breeding in Horticultural Plants, College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
Sugars will eventually be exported transporters (SWEET), a group of relatively novel sugar transporters, that play important roles in phloem loading, seed and fruit development, pollen development, and stress response in plants. Longan (Dimocarpus longan), a subtropic fruit tree with high economic value, is sensitive to cold. However, whether the SWEET gene family plays a role in conferring cold tolerance upon longan remains unknown. Here, a total of 20 longan SWEET (DlSWEET) genes were identified, and their phylogenetic relationships, gene structures, cis-acting elements, and tissue-specific expression patterns were systematically analyzed. This family is divided into four clades. Gene structures and motifs analyses indicated that the majority of DlSWEETs in each clade shared similar exon-intron organization and conserved motifs. Tissue-specific gene expression suggested diverse possible functions for DlSWEET genes. Cis-elements analysis and quantitative real-time PCR (qRT-PCR) analysis revealed that DlSWEET1 responded to cold stress. Notably, the overexpression of DlSWEET1 improved cold tolerance in transgenic Arabidopsis, suggesting that DlSWEET1 might play a positive role in D. longan's responses to cold stress. Together, these results contribute to a better understanding of SWEET genes, which could serve as a foundation for the further functional identification of these genes.
PMID: 36012186
Int J Mol Sci , IF:5.923 , 2022 Jul , V23 (15) doi: 10.3390/ijms23158424
Identification of Chilling-Responsive Genes in Litchi chinensis by Transcriptomic Analysis Underlying Phytohormones and Antioxidant Systems.
Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (South China), Ministry of Agriculture and Rural Affairs, College of Horticulture, South China Agricultural University, Guangzhou 510642, China.
Litchi (Litchi chinensis Sonn.) is an important subtropical and tropical evergreen fruit tree that is seriously affected by chilling stress. In order to identify genes that may be involved in the response to chilling in litchi, we investigate the physiological and biochemical changes under chilling stress and construct 12 RNA-Seq libraries of leaf samples at 0, 4, 8, and 12 days of chilling. The results show that antioxidant enzymes are activated by chilling treatments. Comparing the transcriptome data of the four time points, we screen 2496 chilling-responsive genes (CRGs), from which we identify 63 genes related to the antioxidant system (AO-CRGs) and 54 ABA, 40 IAA, 37 CTK, 27 ETH, 21 BR, 13 GA, 35 JA, 29 SA, and 4 SL signal transduction-related genes. Expression pattern analysis shows that the expression trends of the 28 candidate genes detected by qRT-PCR are similar to those detected by RNA-Seq, indicating the reliability of our RNA-Seq data. Partial Least Squares Structural Equation Modeling (PLS-SEM) analysis of the RNA-Seq data suggests a model for the litchi plants in response to chilling stress that alters the expression of the plant hormone signaling-related genes, the transcription factor-encoding genes LcICE1, LcCBFs, and LcbZIPs, and the antioxidant system-related genes. This study provides candidate genes for the future breeding of litchi cultivars with high chilling resistance, and elucidates possible pathways for litchi in response to chilling using transcriptomic data.
PMID: 35955559
Int J Mol Sci , IF:5.923 , 2022 Jul , V23 (14) doi: 10.3390/ijms23147634
Wheat Elongator Subunit 4 Negatively Regulates Freezing Tolerance by Regulating Ethylene Accumulation.
Crop Research Institute, Shandong Academy of Agricultural Sciences/National Engineering Research Center of Wheat and Maize/Shandong Technology Innovation Center of Wheat, Jinan 252100, China.; Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Freezing stress is a major factor limiting production and geographical distribution of temperate crops. Elongator is a six subunit complex with histone acetyl-transferase activity and is involved in plant development and defense responses in Arabidopsis thaliana. However, it is unknown whether and how an elongator responds to freezing stress in plants. In this study, we found that wheat elongator subunit 4 (TaELP4) negatively regulates freezing tolerance through ethylene signaling. TaELP4 promoter contained cold response elements and was up-regulated in freezing stress. Subcellular localization showed that TaELP4 and AtELP4 localized in the cytoplasm and nucleus. Silencing of TaELP4 in wheat with BSMV-mediated VIGS approach significantly elevated tiller survival rate compared to control under freezing stress, but ectopic expression of TaELP4 in Arabidopsis increased leaf damage and survival rate compared with Col-0. Further results showed that TaELP4 positively regulated ACS2 and ACS6 transcripts, two main limiting enzymes in ethylene biosynthesis. The determination of ethylene content showed that TaELP4 overexpression resulted in more ethylene accumulated than Col-0 under freezing stress. Epigenetic research showed that histone H3K9/14ac levels significantly increased in coding/promoter regions of AtACS2 and AtACS6 in Arabidopsis. RT-qPCR assays showed that the EIN2/EIN3/EIL1-CBFs-COR pathway was regulated by TaELP4 under freezing stress. Taken together, our results suggest that TaELP4 negatively regulated plant responses to freezing stress via heightening histone acetylation levels of ACS2 and ACS6 and increasing their transcription and ethylene accumulation.
PMID: 35886984
Int J Mol Sci , IF:5.923 , 2022 Jul , V23 (14) doi: 10.3390/ijms23147969
Mutations in Rht-B1 Locus May Negatively Affect Frost Tolerance in Bread Wheat.
Department of Plant Physiology and Metabolomics, Agricultural Institute, Centre for Agricultural Research, ELKH, Brunszvik u. 2., H-2462 Martonvasar, Hungary.; Department of Plant Ecophysiology, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria.
The wheat semi-dwarfing genes Rht (Reduced height) are widely distributed among the contemporary wheat varieties. These genes also exert pleiotropic effects on plant tolerance towards various abiotic stressors. In this work, frost tolerance was studied in three near-isogenic lines of the facultative variety 'April Bearded' (AB), carrying the wild type allele Rht-B1a (tall phenotype), and the mutant alleles Rht-B1b (semi-dwarf) and Rht-B1c (dwarf), and was further compared with the tolerance of a typical winter type variety, 'Mv Beres'. The level of freezing tolerance was decreasing in the order 'Mv Beres' > AB Rht-B1a > AB Rht-B1b > AB Rht-B1c. To explain the observed differences, cold acclimation-related processes were studied: the expression of six cold-related genes, the phenylpropanoid pathway, carbohydrates, amino acids, polyamines and compounds in the tricarboxylic acid cycle. To achieve this, a comprehensive approach was applied, involving targeted analyses and untargeted metabolomics screening with the help of gas chromatography/liquid chromatography-mass spectrometry setups. Several cold-related processes exhibited similar changes in these genotypes; indeed, the accumulation of eight putrescine and agmatine derivatives, 17 flavones and numerous oligosaccharides (max. degree of polymerization 18) was associated with the level of freezing tolerance in the 'April Bearded' lines. In summary, the mutant Rht alleles may further decrease the generally low frost tolerance of the Rht-B1a, and, based on the metabolomics study, the mechanisms of frost tolerance may differ for a typical winter variety and a facultative variety. Present results point to the complex nature of frost resistance.
PMID: 35887316
J Fungi (Basel) , IF:5.816 , 2022 Jul , V8 (8) doi: 10.3390/jof8080810
AGC/AKT Protein Kinase SCH9 Is Critical to Pathogenic Development and Overwintering Survival in Magnaporthe oryzae.
The Key Laboratory for Extreme-Environmental Microbiology, College of Plant Protection, Shenyang Agricultural University, Shenyang 110866, China.
Primary inoculum that survives overwintering is one of the key factors that determine the outbreak of plant disease. Pathogenic resting structures, such as chlamydospores, are an ideal inoculum for plant disease. Puzzlingly, Magnaporthe oryzae, a devastating fungal pathogen responsible for blast disease in rice, hardly form any morphologically changed resting structures, and we hypothesize that M. oryzae mainly relies on its physiological alteration to survive overwintering or other harsh environments. However, little progress on research into regulatory genes that facilitate the overwintering of rice blast pathogens has been made so far. Serine threonine protein kinase AGC/AKT, MoSch9, plays an important role in the spore-mediated pathogenesis of M. oryzae. Building on this finding, we discovered that in genetic and biological terms, MoSch9 plays a critical role in conidiophore stalk formation, hyphal-mediated pathogenesis, cold stress tolerance, and overwintering survival of M. oryzae. We discovered that the formation of conidiophore stalks and disease propagation using spores was severely compromised in the mutant strains, whereas hyphal-mediated pathogenesis and the root infection capability of M. oryzae were completely eradicated due to MoSch9 deleted mutants' inability to form an appressorium-like structure. Most importantly, the functional and transcriptomic study of wild-type and MoSch9 mutant strains showed that MoSch9 plays a regulatory role in cold stress tolerance of M. oryzae through the transcription regulation of secondary metabolite synthesis, ATP hydrolyzing, and cell wall integrity proteins during osmotic stress and cold temperatures. From these results, we conclude that MoSch9 is essential for fungal infection-related morphogenesis and overwintering of M. oryzae.
PMID: 36012798
Front Plant Sci , IF:5.753 , 2022 , V13 : P919676 doi: 10.3389/fpls.2022.919676
Clock-Controlled and Cold-Induced CYCLING DOF FACTOR6 Alters Growth and Development in Arabidopsis.
Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA, United States.; Department of Biology, University of Washington, Seattle, WA, United States.
The circadian clock represents a critical regulatory network, which allows plants to anticipate environmental changes as inputs and promote plant survival by regulating various physiological outputs. Here, we examine the function of the clock-regulated transcription factor, CYCLING DOF FACTOR 6 (CDF6), during cold stress in Arabidopsis thaliana. We found that the clock gates CDF6 transcript accumulation in the vasculature during cold stress. CDF6 mis-expression results in an altered flowering phenotype during both ambient and cold stress. A genome-wide transcriptome analysis links CDF6 to genes associated with flowering and seed germination during cold and ambient temperatures, respectively. Analysis of key floral regulators indicates that CDF6 alters flowering during cold stress by repressing photoperiodic flowering components, FLOWERING LOCUS T (FT), CONSTANS (CO), and BROTHER OF FT (BFT). Gene ontology enrichment further suggests that CDF6 regulates circadian and developmental-associated genes. These results provide insights into how the clock-controlled CDF6 modulates plant development during moderate cold stress.
PMID: 35958204
Front Plant Sci , IF:5.753 , 2022 , V13 : P944269 doi: 10.3389/fpls.2022.944269
Transcriptomic Analysis Reveals Potential Gene Regulatory Networks Under Cold Stress of Loquat (Eriobotrya japonica Lindl.).
Forestry and Pomology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China.; Shanghai Key Laboratory of Horticultural Technology, Shanghai Academy of Agricultural Sciences, Shanghai, China.
Loquat (Eriobotrya japonica Lindl. ) is one of the most economically important evergreen fruit crops in China, while it often suffered the injury of cold stress in winter and earlier spring, and the annual yield loss of loquat fruits caused by cold or freezing stress was immeasurable. However, knowledge about the physiological response and molecular mechanism under cold stress is still limited. To investigate the potential regulation mechanism pre- and post-cold stress in loquat and the changes in physiological indicators, a comparative transcriptome analysis was performed against a cold-resistant cv. "Huoju" and a cold-sensitive cv. "Ninghaibai". The results of physiological indicators related to cold resistance indicated that rachis was most sensitive to cold stress and was considered as the representative organ to directly evaluate cold resistance of loquat based on subordinate function analysis. Here, we compared the transcriptome profiles of rachis pre- and under cold stress in "Huoju" and "Ninghaibai". A total of 4,347 and 3,513 differentially expressed genes (DEGs) were detected in "Ninghaibai" and "Huoju", among which 223 and 166 were newly identified genes, respectively, most of them were functionally enriched in plant hormone signal transduction (Huoju: 142; Ninghaibai: 200), and there were higher plant hormone content and related DEG expression levels in "Huoju" than that of "Ninghaibai". Moreover, a total of 3,309 differentially expressed transcription factors (DETFs) were identified, and some DEGs and DETFs were screened to be subjected to co-expression network analysis based on the gene expression profile data. Some candidate DEGs, including UDP-glycosyltransferase (UGT), glycosyltransferase (GT), sugar phosphate/phosphate translocator (SPT), sugar transport protein (STP), proline-rich receptor-like protein kinase (PERK), and peroxidise (POD), were significantly affected by cold stress, and the expression level of these genes obtained from real-time quantitative RT-PCR was consistent with the pattern of transcriptome profile, which suggested that these genes might play the vital roles in cold resistance of loquat. Our results provide an invaluable resource for the identification of specific genes and TFs and help to clarify gene transcription during the cold stress response of loquat.
PMID: 35937353
Front Plant Sci , IF:5.753 , 2022 , V13 : P945394 doi: 10.3389/fpls.2022.945394
Temperature- and light stress adaptations in Zygnematophyceae: The challenges of a semi-terrestrial lifestyle.
Department of Botany, Functional Plant Biology, University of Innsbruck, Innsbruck, Austria.; Department of Biology, Institute for Plant Sciences, University of Cologne, Cologne, Germany.
Streptophyte green algae comprise the origin of land plants and therefore life on earth as we know it today. While terrestrialization opened new habitats, leaving the aquatic environment brought additional abiotic stresses. More-drastic temperature shifts and high light levels are major abiotic stresses in semi-terrestrial habitats, in addition to desiccation, which has been reviewed elsewhere. Zygnematophyceae, a species-rich class of streptophyte green algae, is considered a sister-group to embryophytes. They have developed a variety of avoidance and adaptation mechanisms to protect against temperature extremes and high radiation in the form of photosynthetically active and ultraviolet radiation (UV) radiation occurring on land. Recently, knowledge of transcriptomic and metabolomic changes as consequences of these stresses has become available. Land-plant stress-signaling pathways producing homologs of key enzymes have been described in Zygnematophyceae. An efficient adaptation strategy is their mat-like growth habit, which provides self-shading and protects lower layers from harmful radiation. Additionally, Zygnematophyceae possess phenolic compounds with UV-screening ability. Resting stages such as vegetative pre-akinetes tolerate freezing to a much higher extent than do young cells. Sexual reproduction occurs by conjugation without the formation of flagellated male gametes, which can be seen as an advantage in water-deficient habitats. The resulting zygospores possess a multilayer cell wall, contributing to their resistance to terrestrial conditions. Especially in the context of global change, understanding temperature and light tolerance is crucial.
PMID: 35928713
Front Plant Sci , IF:5.753 , 2022 , V13 : P938339 doi: 10.3389/fpls.2022.938339
Quantitative Trait Loci Mapping Analysis for Cold Tolerance Under Cold Stress and Brassinosteroid-Combined Cold Treatment at Germination and Bud Burst Stages in Rice.
Key Laboratory of Agricultural Biotechnology of Liaoning Province, College of Biosciences and Biotechnology, Shenyang Agricultural University, Shenyang, China.; Rice Research Institute, College of Agronomy, Shenyang Agricultural University, Shenyang, China.; Rice Research Institute, Jiangxi Academy of Agricultural Sciences, Nanchang, China.; Department of Agronomy, College of Agriculture, Purdue University, West Lafayette, IN, United States.
Low temperature is one of the major abiotic stresses limiting seed germination and early seedling growth in rice. Brassinosteroid (BR) application can improve cold tolerance in rice. However, the regulatory relationship between cold tolerance and BR in rice remains undefined. Here, we constructed a population of 140 backcross recombinant inbred lines (BRILs) derived from a cross between a wild rice (Dongxiang wild rice, DXWR) and a super rice (SN265). The low-temperature germination rate (LTG), survival rate (SR), plant height (PH), and first leaf length (FLL) were used as indices for assessing cold tolerance under cold stress and BR-combined cold treatment at seed germination and bud burst stages. A high-resolution SNP genetic map, covering 1,145 bin markers with a distance of 3188.33 cM onto 12 chromosomes, was constructed using the GBS technique. A total of 73 QTLs were detected, of which 49 QTLs were identified under cold stress and 24 QTLs under BR-combined cold treatment. Among these, intervals of 30 QTLs were pairwise coincident under cold stress and BR-combined cold treatment, as well as different traits including SR and FLL, and PH and FLL, respectively. A total of 14 candidate genes related to cold tolerance or the BR signaling pathway, such as CBF/DREB (LOC_Os08g43200), bHLH (LOC_Os07g08440 and LOC_Os07g08440), WRKY (LOC_Os06g30860), MYB (LOC_Os01g62410 and LOC_Os05g51160), and BRI1-associated receptor kinase 1 precursor (LOC_Os06g16300), were located. Among these, the transcript levels of 10 candidate genes were identified under cold stress and BR-combined cold treatment by qRT-PCR. These findings provided an important basis for further mining the genes related to cold tolerance or the BR signaling pathway and understanding the molecular mechanisms of cold tolerance in rice.
PMID: 35923884
Front Plant Sci , IF:5.753 , 2022 , V13 : P930805 doi: 10.3389/fpls.2022.930805
SlCESTA Is a Brassinosteroid-Regulated bHLH Transcription Factor of Tomato That Promotes Chilling Tolerance and Fruit Growth When Over-Expressed.
Biotechnology of Horticultural Crops, TUM School of Life Sciences, Technical University of Munich, Freising, Germany.; Institute of Plant Biology, Technical University of Braunschweig, Braunschweig, Germany.; Plant Growth Regulation, TUM School of Life Sciences, Technical University of Munich, Freising, Germany.
Brassinosteroids (BRs) are required for various aspects of plant growth and development, but also participate in stress responses. The hormones convey their activity through transcriptional regulation and posttranslational modification of transcription factors and one class are basic helix-loop-helix (bHLH) proteins of the BR Enhanced Expression (BEE) subfamily, which in Arabidopsis thaliana include BEE1-3 and CESTA (CES). CES and the BEEs promote the expression of different BR-responsive genes, including genes encoding gibberellin (GA) biosynthetic and catabolizing enzymes, as well as cold-responsive genes. Interestingly, in terms of an application, CES could promote both fruit growth and cold stress tolerance when over-expressed in A. thaliana and here it was investigated, if this function is conserved in the fruit crop Solanum lycopersicum (cultivated tomato). Based on amino acid sequence similarity and the presence of regulatory motifs, a CES orthologue of S. lycopersicum, SlCES, was identified and the effects of its over-expression were analysed in tomato. This showed that SlCES, like AtCES, was re-localized to nuclear bodies in response to BR signaling activation and that it effected GA homeostasis, with related phenotypes, when over-expressed. In addition, over-expression lines showed an increased chilling tolerance and had altered fruit characteristics. The possibilities and potential limitations of a gain of SlCES function as a breeding strategy for tomato are discussed.
PMID: 35909777
Front Plant Sci , IF:5.753 , 2022 , V13 : P936958 doi: 10.3389/fpls.2022.936958
A Chromosome Level Genome Assembly of a Winter Turnip Rape (Brassica rapa L.) to Explore the Genetic Basis of Cold Tolerance.
College of Agronomy, Gansu Agricultural University, Lanzhou, China.; State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou, China.; State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China.; National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China.; Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan, China.
Winter rapeseed (Brassica rapa L.) is an important overwintering oilseed crop that is widely planted in northwest China and suffers chronic low temperatures in winter. So the cold stress becomes one of the major constraints that limit its production. The currently existing genomes limit the understanding of the cold-tolerant genetic basis of rapeseed. Here we assembled a high-quality long-read genome of B. rapa "Longyou-7" cultivar, which has a cold-tolerant phenotype, and constructed a graph-based pan-genome to detect the structural variations within homologs of currently reported cold-tolerant related genes in the "Longyou-7" genome, which provides an additional elucidation of the cold-tolerant genetic basis of "Longyou-7" cultivar and promotes the development of cold-tolerant breeding in B. rapa.
PMID: 35909760
Genomics , IF:5.736 , 2022 Jul , V114 (4) : P110433 doi: 10.1016/j.ygeno.2022.110433
Dynamicity of histone H3K27ac and H3K27me3 modifications regulate the cold-responsive gene expression in Oryza sativa L. ssp. indica.
Division of Plant Biology, Bose Institute, Unified Academic Campus, EN 80, Sector V, Bidhan Nagar, Kolkata 700091, WB, India.; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India; CSIR-National Botanical Research Institute (CSIR-NBRI), Rana Pratap Marg, Lucknow, Uttar Pradesh 226001, India.; Division of Plant Biology, Bose Institute, Unified Academic Campus, EN 80, Sector V, Bidhan Nagar, Kolkata 700091, WB, India. Electronic address: shubho@jcbose.ac.in.
Cultivated in tropical and subtropical regions, Oryza sativa L. ssp. indica is largely affected by cold-stress, especially at the seedling stage. The present model of the stress-responsive regulatory network in plants entails the role of genetic and epigenetic factors in stress-responsive gene expression. Despite extensive transcriptomic studies, the regulation of various epigenetic factors in plants cold-stress response is less explored. The present study addresses the effect of genome-wide changes of H3K27 modifications on gene expression in IR64 rice, during cold-stress. Our results suggest a positive correlation between the changes in H3K27 modifications and stress-responsive gene activation in indica rice. Cold-induced enrichment of H3K27 acetylation promotes nucleosomal rearrangement, thereby facilitating the accessibility of the transcriptional machinery at the stress-responsive loci for transcription activation. Although H3K27ac exhibits uniform distribution throughout the loci of enriched genes; occupancy of H3K27me3 is biased to intergenic regions. Integration of the ChIP-seq data with transcriptome indicated that upregulation of stress-responsive TFs, photosynthesis-TCA-related, water-deficit genes, redox and JA signalling components, was associated with differential changes of H3K27ac and H3K27me3 levels. Furthermore, cold-induced upregulation of histone acetyltransferases and downregulation of DNA methyltransferases was noted through the antagonistic switch of H3K27ac and H3K27me3. Moreover, motif analysis of H3K27ac and H3K27me3 enriched regions are associated with putative stress responsive transcription factors binding sites, GAGA element and histone H3K27demethylase. Collectively our analysis suggests that differential expression of various chromatin and DNA modifiers coupled with increased H3K27ac and depleted H3K27me3 increases DNA accessibility, thereby promoting transcription of the cold-responsive genes in indica rice.
PMID: 35863676
Plant Sci , IF:4.729 , 2022 Aug , V321 : P111291 doi: 10.1016/j.plantsci.2022.111291
Genome-wide identification of LEA gene family and cold response mechanism of BcLEA4-7 and BcLEA4-18 in non-heading Chinese cabbage [Brassica campestris (syn. Brassica rapa) ssp. chinensis].
State Key Laboratory of Crop Genetics & Germplasm Enhancement, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Ministry of Agriculture and Rural Affairs, PR China; Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Ministry of Education, PR China; Nanjing Suman Plasma Engineering Research Institute, Nanjing Agricultural University, Nanjing 210095, China.; State Key Laboratory of Crop Genetics & Germplasm Enhancement, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Ministry of Agriculture and Rural Affairs, PR China; Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Ministry of Education, PR China.; State Key Laboratory of Crop Genetics & Germplasm Enhancement, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Ministry of Agriculture and Rural Affairs, PR China; Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Ministry of Education, PR China; Nanjing Suman Plasma Engineering Research Institute, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: hxl@njau.edu.cn.
Cold stress is a key factor limiting the yield and quality of non-heading Chinese cabbage. The hydrophilic protective protein LEA plays an important role in plant abiotic stress. In this study, 72 BcLEAs were identified from non-heading Chinese cabbage and divided into 9 subfamilies by phylogenetic analysis. Gene structure analysis showed that BcLEAs were unevenly distributed on 10 chromosomes, with few introns. Through analyzing the expression of these genes under cold stress by RNA-seq and qRT-PCR, two genes (BcLEA4-7 and BcLEA4-18) highly sensitive to cold stress were identified, whose roles in cold tolerance of non-heading Chinese cabbage were demonstrated by virus-induced gene silencing. The BcLEA promoters were analyzed to study the cold response mechanism of BcLEA4-7 and BcLEA4-18, revealing that both BcLEA4-7 and BcLEA4-18 promoters contained two CRT/DRE elements. Subsequently, it was found that the promoters isolated from non-heading Chinese cabbage could be activated at low temperatures. Further analysis showed BcCBF2 in non-heading Chinese cabbage interacted with two CRT/DRE elements in BcLEA4-7 and BcLEA4-18 promoters to stimulate their activity, indicating that BcCBF2 is an upstream regulator. Meanwhile, the CRT/DRE element located in BcLEA4-7 promoter (-219bp to -171bp) and BcLEA4-18 promoter (-234bp to -186bp) was more likely to be activated by BcCBF2, which may be attributed to its flanking sequence. These data laid a foundation for further understanding the functional role and regulatory mechanism of BcLEAs in cold stress tolerance.
PMID: 35696933
Plant Sci , IF:4.729 , 2022 Aug , V321 : P111314 doi: 10.1016/j.plantsci.2022.111314
Genome-wide analysis of the apple family 1 glycosyltransferases identified a flavonoid-modifying UGT, MdUGT83L3, which is targeted by MdMYB88 and contributes to stress adaptation.
The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, Shandong University, Qingdao 266237, PR China.; School of Pharmacy, Liaocheng University, Liaocheng, Shandong 250000, PR China.; State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong 271018, PR China.; Shandong Agriculture and Engineering University, Jinan, Shandong 250100, PR China.; Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA.; Science and Technology Development Center of Ministry of Agriculture and Rural Affairs, PR China.; School of Pharmacy, Liaocheng University, Liaocheng, Shandong 250000, PR China. Electronic address: jilusha@lcu.edu.cn.; State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong 271018, PR China. Electronic address: shizhong@sdau.edu.cn.
The plant family 1 UDP-glycosyltransferases (UGTs) are increasingly being investigated because of their contribution to plant secondary metabolism and other diverse biological roles. The apple (Malus domestica) is one of the most widely cultivated fruit trees with great economic importance. However, little is known regarding the apple UGTs. In this study, we identified 229 members of family 1 through a genome-wide analysis of the apple UGTs, which were clustered into 18 groups, from A to R. We also performed detailed analysis of 34 apple UGTs by quantitative RT-PCR, and discovered a number of stress-regulated UGTs. Among them, we characterized the role of MD09G1064900, also named MdUGT83L3, which was significantly induced by salt and cold. In vivo analysis showed that it has high activity towards cyanidin, and moderate activity towards quercetin and keampferol. Transgenic callus and regenerated apple plants overexpressing MdUGT83L3 showed enhanced tolerance to salt and cold treatments. Overexpression of MdUGT83L3 also increased anthocyanin accumulation in the callus tissues and enhanced ROS clearing upon exposure to salt and cold stresses. Furthermore, via yeast-one-hybrid assay, EMSA and CHIP analyses, we also found that MdUGT83L3 could be directly regulated by MdMYB88. Our study indicated that MdUGT83L3, under the regulation of MdMYB88, plays important roles in salt and cold stress adaptation via modulating flavonoid metabolism in apple.
PMID: 35696914
Plant Cell Rep , IF:4.57 , 2022 Aug , V41 (8) : P1673-1691 doi: 10.1007/s00299-022-02883-w
VaMYB44 transcription factor from Chinese wild Vitis amurensis negatively regulates cold tolerance in transgenic Arabidopsis thaliana and V. vinifera.
College of Horticulture, Northwest A&F University, Yangling, Xianyang, 712100, Shaanxi, China.; Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Yangling, Xianyang, 712100, Shaanxi, China.; State Key Laboratory of Crop Stress Biology in Arid Areas, Northwest A&F University, Yangling, Xianyang, 712100, Shaanxi, China.; College of Horticulture, Northwest A&F University, Yangling, Xianyang, 712100, Shaanxi, China. zhangjx666@126.com.; Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Yangling, Xianyang, 712100, Shaanxi, China. zhangjx666@126.com.; State Key Laboratory of Crop Stress Biology in Arid Areas, Northwest A&F University, Yangling, Xianyang, 712100, Shaanxi, China. zhangjx666@126.com.
KEY MESSAGE: Heterologous expression of VaMYB44 gene in Arabidopsis and V. vinifera cv. 'Thompson Seedless' increases cold sensitivity, which is mediated by the interaction of VaMYC2 and VaTIFY5A with VaMYB44 MYB transcription factors play critical roles in plant stress response. However, the function of MYB44 under low temperature stress is largely unknown in grapes. Here, we isolated a VaMYB44 gene from Chinese wild Vitis amurensis acc. 'Shuangyou' (cold-resistant). The VaMYB44 is expressed in various organs and has lower expression levels in stems and young leaves. Exposure of the cold-sensitive V. vinifera cv. 'Thompson Seedless' and cold-resistant 'Shuangyou' grapevines to cold stress (-1 degrees C) resulted in differential expression of MYB44 in leaves with the former reaching 14 folds of the latter after 3 h of cold stress. Moreover, the expression of VaMYB44 was induced by exogenous ethylene, abscisic acid, and methyl jasmonate in the leaves of 'Shuangyou'. Notably, the subcellular localization assay identified VaMYB44 in the nucleus. Interestingly, heterologous expression of VaMYB44 in Arabidopsis and 'Thompson Seedless' grape increased freezing-induced damage compared to their wild-type counterparts. Accordingly, the transgenic lines had higher malondialdehyde content and electrolyte permeability, and lower activities of superoxide dismutase, peroxidase, and catalase. Moreover, the expression levels of some cold resistance-related genes decreased in transgenic lines. Protein interaction assays identified VaMYC2 and VaTIFY5A as VaMYB44 interacting proteins, and VaMYC2 could bind to the VaMYB44 promoter and promote its transcription. In conclusion, the study reveals VaMYB44 as the negative regulator of cold tolerance in transgenic Arabidopsis and transgenic grapes, and VaMYC2 and VaTIFY5A are involved in the cold sensitivity of plants by interacting with VaMYB44.
PMID: 35666271
Plant Cell Rep , IF:4.57 , 2022 Aug doi: 10.1007/s00299-022-02905-7
Drought priming induces chilling tolerance and improves reproductive functioning in chickpea (Cicer arietinum L.).
Centre for Biosciences, School of Basic and Applied Sciences, Central University of Punjab, Bathinda, 151401, India.; Department of Botany, School of Biological Sciences, Central University of Punjab, Bathinda, 151401, India.; Department of Plant Breeding and Genetics, Punjab Agriculture University, Ludhiana, 141004, India.; Department of Botany, Panjab University, Chandigarh, 160014, India.; Centre for Biosciences, School of Basic and Applied Sciences, Central University of Punjab, Bathinda, 151401, India. sanjeevpuchd@gmail.com.; Department of Botany, School of Biological Sciences, Central University of Punjab, Bathinda, 151401, India. sanjeevpuchd@gmail.com.
KEY MESSAGE: Priming alleviates membrane damage, chlorophyll degradation along with cryoprotectants accumulation during chilling stress that leads to improved reproductive functioning and increased seed yield. Chilling temperatures below 15 degrees C have severe implications on the reproductive growth and development of chickpea. The abnormal reproductive development and subsequent reproductive failure lead to substantial yield loss. We exposed five chickpea cultivars (PBG1, GPF2, PDG3, PDG4, and PBG5) to drought stress (Priming) during the vegetative stage and analyzed for chilling tolerance during the reproductive stage. These varieties were raised in the fields in two sets: one set of plants were subjected to drought stress at the vegetative stage for 30 days (priming) and the second set of plants were irrigated regularly (non-primed). The leaf samples were harvested at the flowering, podding, and seed filling stage and analyzed for membrane damage, water status, chlorophyll content, cellular respiration, and certain cryoprotective solutes. The reproductive development was analyzed by accessing pollen viability, in vivo and in vitro germination, pollen load, and in vivo pollen tube growth. Principal component analysis (PCA) revealed that priming improved membrane damage, chlorophyll b degradation, and accumulation of cryoprotectants in GPF2, PDG3, and PBG5 at the flowering stage (< 15 degrees C). Pearson's correlation analysis showed a negative correlation with the accumulation of proline and carbohydrates with flower, pod, and seed abortion. Only, PBG5 responded best to priming while PBG1 was worst. In PBG5, priming resulted in reduced membrane damage and lipid peroxidation, improved water content, reduced chlorophyll degradation, and enhanced cryoprotective solutes accumulation, which led to increased reproductive functioning and finally improved seed yield and harvest index. Lastly, the priming response is variable and cultivar-specific but overall improve plant tolerance.
PMID: 35916939
Sci Rep , IF:4.379 , 2022 Jul , V12 (1) : P11593 doi: 10.1038/s41598-022-15821-3
Photosynthetic response and antioxidative activity of 'Hass' avocado cultivar treated with short-term low temperature.
Research Institute of Climate Change and Agriculture, National Institute of Horticultural and Herbal Science, Jeju, 63240, Republic of Korea. jsw599@korea.kr.; Department of Horticulture and Landscape Architecture, National Taiwan University, Taipei, 10617, Taiwan.; Research Institute of Climate Change and Agriculture, National Institute of Horticultural and Herbal Science, Jeju, 63240, Republic of Korea.
To investigate the effects of short-term low temperatures, three-year-old avocado (Persea americana cv. Hass) seedlings were treated with 1, - 2, or - 5 degrees C for 1 h and subsequently recovered in ambient condition for 24 h. Leaf color changes were investigated with chlorophyll, carotenoid, and phenolic contents. Photosynthetic responses were examined using gas exchange analysis. With H2O2 contents as oxidative stresses, enzymatic (ascorbate peroxidase, APX; glutathione reductase, GR; catalase, CAT; peroxidase, POD) and non-enzymatic antioxidant activities were determined using spectrophotometry. Leaves in the avocado seedlings started to be discolored with changes in the contents of chlorophyll a, carotenoids, and phenolics when treated with - 5 degrees C. However, the H2O2 content was not different in leaves treated with low temperatures. Photosynthetic activities decreased in leaves in the seedlings treated with - 5 degrees C. Of antioxidant enzymes, APX and GR have high activities in leaves in the seedlings treated with 1 and - 2 degrees C. In leaves in the seedlings treated with - 5 degrees C, the activities of all enzymes decreased. Non-enzymatic antioxidant activity was not different among leaves treated with low temperatures. These results indicated that APX and GR would play a critical role in withstanding chilling stress in 'Hass' avocado seedlings. However, under lethal temperature, even for a short time, the plants suffered irreversible damage with the breakdown of photosystem and antioxidant system.
PMID: 35804002
Plant Physiol Biochem , IF:4.27 , 2022 Aug , V185 : P13-24 doi: 10.1016/j.plaphy.2022.05.030
Genome-wide identification of YABBY transcription factors in Brachypodium distachyon and functional characterization of Bd DROOPING LEAF.
State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712000, Shaanxi, China. Electronic address: chenshoukun@nwsuaf.edu.cn.; State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712000, Shaanxi, China. Electronic address: Houjiayuan@nwafu.edu.cn.; State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712000, Shaanxi, China. Electronic address: fuyanan@nwafu.edu.cn.; State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712000, Shaanxi, China. Electronic address: lhf@nwsuaf.edu.cn.
YABBY transcription factors (TFs) are plant-specific and are characterized by a C2-C2 zinc finger domain at the N-terminus and a YABBY domain at the C-terminus. In this study, eight YABBY genes were identified in the Brachypodium distachyon genome and were unevenly distributed across four chromosomes. Phylogenetic analysis classified BdYABBYs into FIL/YAB3, YAB2, CRC, and INO clades. Sixty-two putative cis-elements were identified in BdYABBY gene putative promoters, among them, CAAT-box, TATA-box, MYB, MYC, ARE, and Box_4 were shared by all. BdYABBY genes are highly expressed in inflorescences, and abiotic stresses regulate their expression. In addition, three transcripts of BdDL were identified. Over-expression in Arabidopsis has shown their different functions in reproductive development, as well as in response to cold stress. Our study lays the foundation for the functional elucidation of BdYABBY genes.
PMID: 35640497
Environ Sci Pollut Res Int , IF:4.223 , 2022 Aug doi: 10.1007/s11356-022-22013-z
Chicken feather protein hydrolysate improves cold resistance by upregulating physiologic and biochemical responses of wheat (Triticum aestivum L.).
Department of Biology, Faculty of Science, Ataturk University, 25240, Erzurum, Turkey.; Department of Biology, Faculty of Science, Ataturk University, 25240, Erzurum, Turkey. otici@atauni.edu.tr.
Chicken feather (CF) is one of the largest by-products of the poultry industry and millions of tons of feathers from poultry processing plants have caused a serious waste issue in almost every country. We produced a chicken feather protein hydrolysate (CFPH) by an alkaline process and investigated its effect on the low-temperature response of two wheat cultivars (Triticum aestivum L., cvs. Altindane and Bezostaja). The CFPH contained 19 proteinogenic and 3 non-proteinogenic amino acids, as well as beneficial salts for plant growth. The aqueous solution of CFPH (0.1%, w/v) was applied to seedling leaves before cold stress and then the seedlings (treated and untreated) were transferred to cold conditions (5/2 degrees C, day/night) for 3 days. The CFPH application increased the expression of Rubisco protein and the contents of photosynthetic pigment, soluble sugar, and free proline while decreasing phenolic content in the leaves of both cultivars under cold stress. The cold application alone increased the levels of reactive oxygen species (ROS) and lipid peroxidation (as malondialdehyde), while CFPH decreased their levels. Compared to cold alone, CFPH stimulated antioxidant enzyme activities in both cultivars. This finding was supported by the changes in isoenzyme profiles of the same enzymes on native PAGE. In addition, CFPH application raised reduced ascorbate and glutathione levels, while decreasing the levels of their oxidized forms. The results showed that the application of waste CF-derived CFPH to leaves as a biostimulant alleviated physiological and antioxidative responses in the wheat seedlings under cold stress, thus having the potential to increase cold-stress tolerance in wheat.
PMID: 35947261
Environ Sci Pollut Res Int , IF:4.223 , 2022 Aug , V29 (36) : P55235-55249 doi: 10.1007/s11356-022-19759-x
Gold nanoparticles as adaptogens increazing the freezing tolerance of wheat seedlings.
K.A. Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Moscow, 127276, Russia. jul.venzhik@gmail.com.; K.A. Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Moscow, 127276, Russia.; Institute of Biochemistry and Physiology of Plants and Microorganisms, Saratov Scientific Centre of the Russian Academy of Sciences, Saratov, 410049, Russia.
The intensive development of nanotechnology led to the widespread application of various nanoparticles and nanomaterials. As a result, nanoparticles enter the environment and accumulate in ecosystems and living organisms. The consequences of possible impact of nanoparticles on living organisms are not obvious. Experimental data indicate that nanoparticles have both toxic and stimulating effects on organisms. In this study, we demonstrated for the first time that gold nanoparticles can act as adaptogens increasing plant freezing tolerance. Priming winter wheat (Triticum aestivum L., var. Moskovskaya 39, Poaceae) seeds for 1 day in solutions of gold nanoparticles (15-nm diameter, concentrations of 5, 10, 20, and 50 microg/ml) led to an increase in freezing tolerance of 7-day-old wheat seedlings. A relationship between an increase in wheat freezing tolerance and changes in some important indicators for its formation-growth intensity, the activity of the photosynthetic apparatus and oxidative processes, and the accumulation of soluble sugars in seedlings-was established. Assumptions on possible mechanisms of gold nanoparticles effects on plant freezing tolerance are discussed.
PMID: 35316488
BMC Plant Biol , IF:4.215 , 2022 Aug , V22 (1) : P398 doi: 10.1186/s12870-022-03787-3
Full-length transcriptome analysis of maize root tips reveals the molecular mechanism of cold stress during the seedling stage.
Institute of Nanfan & Seed Industry, Guangdong Academy of Science, Guangzhou, 510316, Guangdong, China.; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, Guangdong, China.; College of Agriculture and Biology, Zhongkai University of Agriculture and Engineering, Guangzhou, 510325, Guangdong, China.; College of Agriculture, Yangtze University, Jingzhou, 434025, Hubei, China.; Institute of Nanfan & Seed Industry, Guangdong Academy of Science, Guangzhou, 510316, Guangdong, China. yongwen2001@126.com.; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, Guangdong, China. yongwen2001@126.com.; College of Agriculture and Biology, Zhongkai University of Agriculture and Engineering, Guangzhou, 510325, Guangdong, China. yongwen2001@126.com.
BACKGROUND: As maize originated in tropical or subtropical zones, most maize germplasm is extremely sensitive to low temperatures during the seedling stage. Clarifying the molecular mechanism of cold acclimation would facilitate the breeding of cold tolerant maize varieties, which is one of the major sustainability factors for crop production. To meet this goal, we investigated two maize inbred lines with contrasting levels of cold tolerance at the seedling stage (IL85, a cold tolerant line; B73, a cold sensitive line), and performed full-length transcriptome sequencing on the root tips of seedlings before and after 24 h of cold treatment. RESULTS: We identified 152,263 transcripts, including 20,993 novel transcripts, and determined per-transcript expression levels. A total of 1,475 transcripts were specifically up-regulated in the cold tolerant line IL85 under cold stress. GO enrichment analysis revealed that 25 transcripts were involved in reactive oxygen species (ROS) metabolic processes and 15 transcripts were related to the response to heat. Eight genes showed specific differential alternative splicing (DAS) in IL85 under cold stress, and were mainly involved in amine metabolism. A total of 1,111 lncRNAs were further identified, 62 of which were up-regulated in IL85 or B73 under cold stress, and their corresponding target genes were enriched in protein phosphorylation. CONCLUSIONS: These results provide new insights into the molecular mechanism of cold acclimation during the seedling stage in maize, and will facilitate the development of cultivars with improved cold stress tolerance.
PMID: 35963989
BMC Plant Biol , IF:4.215 , 2022 Jul , V22 (1) : P378 doi: 10.1186/s12870-022-03770-y
Genetic and genomic diversity in the sorghum gene bank collection of Uganda.
Department of Plant Breeding, Justus Liebig University, Giessen, Germany.; Uganda National Gene Bank, National Agricultural Research Laboratories, Kampala, Uganda.; Queensland Alliance for Agriculture and Food Innovation, University of Queensland, Warwick, QLD, 4370, Australia.; Department of Plant Breeding, Justus Liebig University, Giessen, Germany. Rod.Snowdon@agrar.uni-giessen.de.
BACKGROUND: The Plant Genetic Resources Centre at the Uganda National Gene Bank houses has over 3000 genetically diverse landraces and wild relatives of Sorghum bicolor accessions. This genetic diversity resource is untapped, under-utilized, and has not been systematically incorporated into sorghum breeding programs. In this study, we characterized the germplasm collection using whole-genome SNP markers (DArTseq). Discriminant analysis of principal components (DAPC) was implemented to study the racial ancestry of the accessions in comparison to a global sorghum diversity set and characterize the sub-groups present in the Ugandan (UG) germplasm. RESULTS: Population structure and phylogenetic analysis revealed the presence of five subgroups among the Ugandan accessions. The samples from the highlands of the southwestern region were genetically distinct as compared to the rest of the population. This subset was predominated by the caudatum race and unique in comparison to the other sub-populations. In this study, we detected QTL for juvenile cold tolerance by genome-wide association studies (GWAS) resulting in the identification of 4 markers associated (-log10p > 3) to survival under cold stress under both field and climate chamber conditions, located on 3 chromosomes (02, 06, 09). To our best knowledge, the QTL on Sb09 with the strongest association was discovered for the first time. CONCLUSION: This study demonstrates how genebank genomics can potentially facilitate effective and efficient usage of valuable, untapped germplasm collections for agronomic trait evaluation and subsequent allele mining. In face of adverse climate change, identification of genomic regions potentially involved in the adaptation of Ugandan sorghum accessions to cooler climatic conditions would be of interest for the expansion of sorghum production into temperate latitudes.
PMID: 35906543
BMC Plant Biol , IF:4.215 , 2022 Jul , V22 (1) : P369 doi: 10.1186/s12870-022-03767-7
Transcriptome-based gene regulatory network analyses of differential cold tolerance of two tobacco cultivars.
State Key Laboratory for Crop Genetics and Germplasm Enhancement, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, Jiangsu, China.; Hunan Tobacco Research Institute, Changsha, 410128, Hunan, China.; State Key Laboratory for Crop Genetics and Germplasm Enhancement, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, Jiangsu, China. xuejiaocheng@njau.edu.cn.; Hunan Tobacco Research Institute, Changsha, 410128, Hunan, China. 495298768@qq.com.; State Key Laboratory for Crop Genetics and Germplasm Enhancement, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, Jiangsu, China. wzhang25@njau.edu.cn.
BACKGROUND: Cold is one of the main abiotic stresses that severely affect plant growth and development, and crop productivity as well. Transcriptional changes during cold stress have already been intensively studied in various plant species. However, the gene networks involved in the regulation of differential cold tolerance between tobacco varieties with contrasting cold resistance are quite limited. RESULTS: Here, we conducted multiple time-point transcriptomic analyses using Tai tobacco (TT, cold susceptibility) and Yan tobacco (YT, cold resistance) with contrasting cold responses. We identified similar DEGs in both cultivars after comparing with the corresponding control (without cold treatment), which were mainly involved in response to abiotic stimuli, metabolic processes, kinase activities. Through comparison of the two cultivars at each time point, in contrast to TT, YT had higher expression levels of the genes responsible for environmental stresses. By applying Weighted Gene Co-Expression Network Analysis (WGCNA), we identified two main modules: the pink module was similar while the brown module was distinct between the two cultivars. Moreover, we obtained 100 hub genes, including 11 important transcription factors (TFs) potentially involved in cold stress, 3 key TFs in the brown module and 8 key TFs in the pink module. More importantly, according to the genetic regulatory networks (GRNs) between TFs and other genes or TFs by using GENIE3, we identified 3 TFs (ABI3/VP1, ARR-B and WRKY) mainly functioning in differential cold responses between two cultivars, and 3 key TFs (GRAS, AP2-EREBP and C2H2) primarily involved in cold responses. CONCLUSION: Collectively, our study provides valuable resources for transcriptome- based gene network studies of cold responses in tobacco. It helps to reveal how key cold responsive TFs or other genes are regulated through network. It also helps to identify the potential key cold responsive genes for the genetic manipulation of tobacco cultivars with enhanced cold tolerance in the future.
PMID: 35879667
BMC Plant Biol , IF:4.215 , 2022 Jul , V22 (1) : P344 doi: 10.1186/s12870-022-03704-8
Overexpression VaPYL9 improves cold tolerance in tomato by regulating key genes in hormone signaling and antioxidant enzyme.
College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, People's Republic of China.; College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, People's Republic of China. maojuan@gsau.edu.cn.
BACKGROUND: Abscisic acid (ABA) has been reported in controlling plant growth and development, and particularly dominates a role in resistance to abiotic stress. The Pyrabactin Resistance1/PYR1-Like /Regulatory Components of ABA receptors (PYR1/PYL/RCAR) gene family, of which the PYL9 is a positive regulator related to stress response in ABA signaling transduction. Although the family has been identified in grape, detailed VaPYL9 function in cold stress remains unknown. RESULTS: In order to explore the cold tolerance mechanism in grape, VaPYL9 was cloned from Vitis amurensis. The subcellular localization showed that VaPYL9 was mainly expressed in the plasma membrane. Yeast two-hybrid (Y2H) showed VaPCMT might be a potential interaction protein of VaPYL9. Through the overexpression of VaPYL9 in tomatoes, results indicated transgenic plants had higher antioxidant enzyme activities and proline content, lower malondialdehyde (MDA) and H2O2 content, and improving the ability to scavenge reactive oxygen species than wild-type (WT). Additionally, ABA content and the ratio of ABA/IAA kept a higher level than WT. Quantitative real-time PCR (qRT-PCR) showed that VaPYL9, SlNCED3, SlABI5, and antioxidant enzyme genes (POD, SOD, CAT) were up-regulated in transgenic tomatoes. Transcriptome sequencing (RNA-seq) found that VaPYL9 overexpression caused the upregulation of key genes PYR/PYL, PYL4, MAPK17/18, and WRKY in transgenic tomatoes under cold stress. CONCLUSION: Overexpression VaPYL9 enhances cold resistance of transgenic tomatoes mediated by improving antioxidant enzymes activity, reducing membrane damages, and regulating key genes in plant hormones signaling and antioxidant enzymes.
PMID: 35840891
BMC Plant Biol , IF:4.215 , 2022 Jul , V22 (1) : P333 doi: 10.1186/s12870-022-03718-2
Transcription-associated metabolomic profiling reveals the critical role of frost tolerance in wheat.
Institute of Cereal and Oil Crops, Hebei Academy of Agriculture and Forestry Sciences, Crop Genetics and Breeding Laboratory of Hebei, Shijiazhuang, 050000, China.; Handan Academy of Agricultural Sciences, Handan, 056000, Hebei, China.; Institute of Cereal and Oil Crops, Hebei Academy of Agriculture and Forestry Sciences, Crop Genetics and Breeding Laboratory of Hebei, Shijiazhuang, 050000, China. zwslihui@163.com.; Institute of Cereal and Oil Crops, Hebei Academy of Agriculture and Forestry Sciences, Crop Genetics and Breeding Laboratory of Hebei, Shijiazhuang, 050000, China. chenxiyong3691@163.com.
BACKGROUND: Low temperature is a crucial stress factor of wheat (Triticum aestivum L.) and adversely impacts on plant growth and grain yield. Multi-million tons of grain production are lost annually because crops lack the resistance to survive in winter. Particularlly, winter wheat yields was severely damaged under extreme cold conditions. However, studies about the transcriptional and metabolic mechanisms underlying cold stresses in wheat are limited so far. RESULTS: In this study, 14,466 differentially expressed genes (DEGs) were obtained between wild-type and cold-sensitive mutants, of which 5278 DEGs were acquired after cold treatment. 88 differential accumulated metabolites (DAMs) were detected, including P-coumaroyl putrescine of alkaloids, D-proline betaine of mino acids and derivativ, Chlorogenic acid of the Phenolic acids. The comprehensive analysis of metabolomics and transcriptome showed that the cold resistance of wheat was closely related to 13 metabolites and 14 key enzymes in the flavonol biosynthesis pathway. The 7 enhanced energy metabolites and 8 up-regulation key enzymes were also compactly involved in the sucrose and amino acid biosynthesis pathway. Moreover, quantitative real-time PCR (qRT-PCR) revealed that twelve key genes were differentially expressed under cold, indicating that candidate genes POD, Tacr7, UGTs, and GSTU6 which were related to cold resistance of wheat. CONCLUSIONS: In this study, we obtained the differentially expressed genes and differential accumulated metabolites in wheat under cold stress. Using the DEGs and DAMs, we plotted regulatory pathway maps of the flavonol biosynthesis pathway, sucrose and amino acid biosynthesis pathway related to cold resistance of wheat. It was found that candidate genes POD, Tacr7, UGTs and GSTU6 are related to cold resistance of wheat. This study provided valuable molecular information and new genetic engineering clues for the further study on plant resistance to cold stress.
PMID: 35820806
BMC Plant Biol , IF:4.215 , 2022 Aug , V22 (1) : P414 doi: 10.1186/s12870-022-03797-1
Integrated methylome and transcriptome analysis unravel the cold tolerance mechanism in winter rapeseed(Brassica napus L.).
State Key Laboratory of Aridland Crop Sciences, Lanzhou, China.; College of Agronomy, Gansu Agricultural University, Lanzhou, China.; State Key Laboratory of Aridland Crop Sciences, Lanzhou, China. lzgworking@163.com.; College of Agronomy, Gansu Agricultural University, Lanzhou, China. lzgworking@163.com.; Affiliation Faculty of Agriculture and Veterinary Sciences, Superior University, Lahore, Pakistan.
BACKGROUND: Cytosine methylation, the main type of DNA methylation, regulates gene expression in plant response to environmental stress. The winter rapeseed has high economic and ecological value in China's Northwest, but the DNA methylation pattern of winter rapeseed during freezing stress remains unclear. RESULT: This study integrated the methylome and transcriptome to explore the genome-scale DNA methylation pattern and its regulated pathway of winter rapeseed, using freezing-sensitive (NF) and freezing-resistant (NS) cultivars.The average methylation level decreased under freezing stress, and the decline in NF was stronger than NS after freezing stress. The CG methylation level was the highest among the three contexts of CG, CHG, and CHH. At the same time, the CHH proportion was high, and the methylation levels were highest 2 kb up/downstream, followed by the intron region. The C sub-genomes methylation level was higher than the A sub-genomes. The methylation levels of chloroplast and mitochondrial DNA were much lower than the B. napus nuclear DNA, the SINE methylation level was highest among four types of transposable elements (TEs), and the preferred sequence of DNA methylation did not change after freezing stress. A total of 1732 differentially expressed genes associated with differentially methylated genes (DMEGs) were identified in two cultivars under 12 h and 24 h in three contexts by combining whole-genome bisulfite sequencing( and RNA-Seq data. Function enrichment analysis showed that most DMEGs participated in linoleic acid metabolism, alpha-linolenic acid metabolism, carbon fixation in photosynthetic organisms, flavonoid biosynthesis, and plant hormone signal transduction pathways. Meanwhile, some DMEGs encode core transcription factors in plant response to stress. CONCLUSION: Based on the findings of DNA methylation, the freezing tolerance of winter rapeseed is achieved by enhanced signal transduction, lower lipid peroxidation, stronger cell stability, increased osmolytes, and greater reactive oxygen species (ROS) scavenging. These results provide novel insights into better knowledge of the methylation regulation of tolerance mechanism in winter rapeseed under freezing stress.
PMID: 36008781
Plant Genome , IF:4.089 , 2022 Jul : Pe20229 doi: 10.1002/tpg2.20229
Identifying and expression analysis of WD40 transcription factors in walnut.
Laboratory of Walnut Research Center, College of Forestry, Northwest A & F Univ., Yangling, Shaanxi, 712100, China.; Key Laboratory of Economic Plant Resources Development and Utilization in Shaanxi Province, College of Forestry, Northwest A & F Univ., Yangling, Shaanxi, 712100, China.; College of Forestry, Northwest A & F Univ., Yangling, Shaanxi, 712100, China.
Walnut (Juglans regia L.) is an important woody oil plant and will be affected by abiotic and biological stress during its growth and development. The WD-repeat (WD40) protein is widely involved in plant growth, development, metabolism, and abiotic stress response. To explore the stress response mechanism of walnut, based on the complete sequencing results of the walnut genome, this study identified and analyzed the physiological, biochemical, genetic structure, and conservative protein motifs of 42 JrWD40 genes, whose expression to abnormal temperature were tested to predict the potential biological function. The results showed that the open reading frame (ORF) of theseWD40 genes were 807-2,460 bp, encoding peptides were 29,610.55-90,387.98 Da covering 268-819 amino acids, as well as 12-112 phosphorylation sites. JrWD40 proteins were highly conserved with four to five WD40 domains and shared certain similarity to WD40 proteins from Arabidopsis thaliana (L.) Heynh. JrWD40 genes can be induced to varying degrees by low and high temperature treatments. JrWD40-32, JrWD40-27, JrWD40-35, and JrWD40-21 are affected by high temperature more seriously and their expression levels are higher; while JrWD40-37, JrWD40-26, JrWD40-20, JrWD40-24, and other genes are inhibited under low temperature stress. JrWD40-40, JrWD40-28, and JrWD40-18 were first suppressed with low expression, while as the treatment time prolonging, the expression level was increased under cold condition. JrWD40-14, JrWD40-18, JrWD40-34, and JrWD40-3 displayed strong transcriptions response to both heat and cold stress. These results indicated that JrWD40 genes can participate in walnut adaptation to adversity and can be used as important candidates for walnut resistance molecular breeding.
PMID: 35904050
BMC Genomics , IF:3.969 , 2022 Jul , V23 (1) : P516 doi: 10.1186/s12864-022-08751-x
Computational analysis of potential candidate genes involved in the cold stress response of ten Rosaceae members.
National Centre for Biological Sciences (TIFR), GKVK Campus, Bangalore, Karnataka, 560065, India.; The University of Trans-Disciplinary Health Sciences & Technology (TDU), Yelahanka, Bangalore, Karnataka, 560064, India.; National Centre for Biological Sciences (TIFR), GKVK Campus, Bangalore, Karnataka, 560065, India. mini@ncbs.res.in.; Molecular BIophysics Unit, Indian Institute of Science, 560012, Bangalore, India. mini@ncbs.res.in.
BACKGROUND: Plant species from Rosaceae family are economically important. One of the major environmental factors impacting those species is cold stress. Although several Rosaceae plant genomes have recently been sequenced, there have been very few research conducted on cold upregulated genes and their promoter binding sites. In this study, we used computational approaches to identify and analyse potential cold stress response genes across ten Rosaceae family members. RESULTS: Cold stress upregulated gene data from apple and strawberry were used to identify syntelogs in other Rosaceae species. Gene duplication analysis was carried out to better understand the distribution of these syntelog genes in different Rosaceae members. A total of 11,145 popular abiotic stress transcription factor-binding sites were identified in the upstream region of these potential cold-responsive genes, which were subsequently categorised into distinct transcription factor (TF) classes. MYB classes of transcription factor binding site (TFBS) were abundant, followed by bHLH, WRKY, and AP2/ERF. TFBS patterns in the promoter regions were compared among these species and gene families, found to be quite different even amongst functionally related syntelogs. A case study on important cold stress responsive transcription factor family, AP2/ERF showed less conservation in TFBS patterns in the promoter regions. This indicates that syntelogs from the same group may be comparable at the gene level but not at the level of cis-regulatory elements. Therefore, for such genes from the same family, different repertoire of TFs could be recruited for regulation and expression. Duplication events must have played a significant role in the similarity of TFBS patterns amongst few syntelogs of closely related species. CONCLUSIONS: Our study overall suggests that, despite being from the same gene family, different combinations of TFs may play a role in their regulation and expression. The findings of this study will provide information about potential genes involved in the cold stress response, which will aid future functional research of these gene families involved in many important biological processes.
PMID: 35842574
Plants (Basel) , IF:3.935 , 2022 Jul , V11 (14) doi: 10.3390/plants11141881
Understanding and Comprehensive Evaluation of Cold Resistance in the Seedlings of Multiple Maize Genotypes.
State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou 730070, China.; United States Department of Agriculture, Fargo, ND 58102-2765, USA.
Maize is a cold-sensitive crop, and it exhibits severe retardation of growth and development when exposed to cold snaps during and right after seedling emergence. Although different agronomic, physiological, and molecular approaches have been tried to overcome the problems related to cold stress in recent years, the mechanisms causing cold resistance in maize are still unclear. Screening and breeding of varieties for cold resistance may be a sustainable option to boost maize production under low-temperature environments. Herein, seedlings of 39 different maize genotypes were treated under both 10 degrees C low temperature and 22 degrees C normal temperature conditions for 7 days, to assess the changes in seven growth parameters, two membrane characteristics, two reactive oxygen species (ROS) levels, and four antioxidant enzymes activities. The changes in ten photosynthetic performances, one osmotic substance accumulation, and three polyamines (PAs) metabolisms were also measured. Results indicated that significant differences among genotypes, temperature treatments, and their interactions were found in 29 studied traits, and cold-stressed seedlings were capable to enhance their cold resistance by maintaining high levels of membrane stability index (66.07%); antioxidant enzymes activities including the activity of superoxide dismutase (2.44 Unit g(-1) protein), peroxidase (1.65 Unit g(-1) protein), catalase (0.65 muM min(-1) g(-1) protein), and ascorbate peroxidase (5.45 muM min(-1) g(-1) protein); chlorophyll (Chl) content, i.e., Chl a (0.36 mg g(-1) FW) and Chl b (0.40 mg g(-1) FW); photosynthetic capacity such as net photosynthetic rate (5.52 muM m(-2) s(-1)) and ribulose 1,5-biphosphate carboxylase activity (6.57 M m(-2) s(-1)); PAs concentration, mainly putrescine (274.89 nM g(-1) FW), spermidine (52.69 nM g(-1) FW), and spermine (45.81 nM g(-1) FW), particularly under extended cold stress. Importantly, 16 traits can be good indicators for screening of cold-resistant genotypes of maize. Gene expression analysis showed that GRMZM2G059991, GRMZM2G089982, GRMZM2G088212, GRMZM2G396553, GRMZM2G120578, and GRMZM2G396856 involved in antioxidant enzymes activity and PAs metabolism, and these genes may be used for genetic modification to improve maize cold resistance. Moreover, seven strong cold-resistant genotypes were identified, and they can be used as parents in maize breeding programs to develop new varieties.
PMID: 35890515
Plants (Basel) , IF:3.935 , 2022 Jul , V11 (14) doi: 10.3390/plants11141865
SlHSP17.7 Ameliorates Chilling Stress-Induced Damage by Regulating Phosphatidylglycerol Metabolism and Calcium Signal in Tomato Plants.
College of Horticulture, Shenyang Agricultural University, Shenyang 110866, China.; Institute of Vegetable Science, Liaoning Academy of Agricultural Sciences, Shenyang 110161, China.; Shenyang Institute of Technology, Shenyang 113122, China.; Key Laboratory of Protected Horticulture of Education Ministry, Shenyang 110866, China.
Tomatoes (Solanum lycopersicum L.) are sensitive to chilling temperatures between 0 degrees C and 12 degrees C owing to their tropical origin. SlHSP17.7, a cytoplasmic heat shock protein, interacts with cation/calcium exchanger 1-like (SlCCX1-like) protein and promotes chilling tolerance in tomato fruits (Zhang, et al., Plant Sci., 2020, 298, 1-12). The overexpression of SlHSP17.7 can also promote cold tolerance in tomato plants, but its specific mechanism remains unclear. In this study, we show that the overexpression of SlHSP17.7 in tomato plants enhances chilling tolerance with better activity of photosystem II (PSII). Metabolic analyses revealed that SlHSP17.7 improved membrane fluidity by raising the levels of polyunsaturated fatty acids. Transcriptome analyses showed that SlHSP17.7 activated Ca(2+) signaling and induced the expression of C-repeat binding factor (CBF) genes, which in turn inhibited the production of reactive oxygen species (ROS). The gene coexpression network analysis showed that SlHSP17.7 is coexpressed with SlMED26b. SlMED26b silencing significantly lowered OE-HSP17.7 plants' chilling tolerance. Thus, SlHSP17.7 modulates tolerance to chilling via both membrane fluidity and Ca(2+)-mediated CBF pathway in tomato plants.
PMID: 35890502
Int J Biometeorol , IF:3.787 , 2022 Jul doi: 10.1007/s00484-022-02339-6
Expression profiling of HSP 70 and interleukins 2, 6 and 12 genes of Barki sheep during summer and winter seasons in two different locations.
Department of Animal and Fish Production, Faculty of Agriculture, University of Alexandria, Alexandria, 21545, Egypt.; Department of Livestock Research, Arid Lands Cultivation Research Institute, City for Scientific Research and Technology Applications, New Borg El-Arab, Alexandria, 21934, Egypt.; Faculty of Desert and Environmental Agriculture, Matrouh University, Matrouh, Egypt.; Plant Protection and Biomolecular Diagnosis Department, City of Scientific Research and Technology Applications, Arid Lands Cultivation Research Institute, New Borg El-Arab City, Alexandria, 21934, Egypt.; Department of Animal and Fish Production, Faculty of Agriculture, University of Alexandria, Alexandria, 21545, Egypt. mmisalem@gmail.com.
The objectives of this research were to contrast the expression values of heat shock protein (HSP70) and interleukins 2, 6 and 12 (IL 2, IL 6 and IL 12) genes in summer and winter in two different locations in Egypt (Alexandria zone and Matrouh zone) to deduce changes in thermo-physiological traits and biochemical blood metabolites of Barki sheep. A total of 50 ewes (20 in Alexandria and 30 in Matrouh) were individually blood sampled to determine plasma total protein (TP), Albumin, Globulin and Glucose constituents and T3, T4 and cortisol hormones. The thermo-physiological parameters of rectal temperature (RT, degrees C), skin temperature (ST, degrees C), Wool temperature (WT, degrees C), respiration rate (RR, breaths/min) and pulse rate (PR, beats/min) were measured for each ewe. Expressions of IL 2, IL 6, IL 12 and HSP 70 in summer and winter were analyzed along with thermo-physiological parameters and blood biochemical metabolites. In both locations, THI had significant effects on ST, WT, PR and RR, but not significant on RT. However, it had no significant effects on blood plasma metabolites and hormonal concentrations in the two locations in summer and winter. In Alexandria location, THI had negative significant effect on the expressions of IL-2 and IL-6 but positively affected on HSP70 genes in winter, while the expression of IL-12 gene was not affected by seasons, whereas in Matrouh zone, the effects of THI on the expressions of all tolerance genes were not significant. The results of the current study suggest that IL-2, IL-6 and HSP70 genes could be used as molecular markers for heat/cold stress.
PMID: 35882644
Gene , IF:3.688 , 2022 Aug , V837 : P146690 doi: 10.1016/j.gene.2022.146690
Genome-wide identification of cold-tolerance genes and functional analysis of IbbHLH116 gene in sweet potato.
Research Center of Crop Stresses Resistance Technologies/ Engineering Research Centre of Ecology and Agricultural Use of Wetland, Ministry of Education, Yangtze University, Jingzhou 434025, China.; Agronomy Department, Faculty of Agriculture, Assiut University, 71526 Assiut, Egypt.; Research Center of Crop Stresses Resistance Technologies/ Engineering Research Centre of Ecology and Agricultural Use of Wetland, Ministry of Education, Yangtze University, Jingzhou 434025, China; Hubei Sweet potato Engineering and Technology Research Centre, Hubei Academy of Agricultural Sciences, Wuhan 430064, China.; Hubei Sweet potato Engineering and Technology Research Centre, Hubei Academy of Agricultural Sciences, Wuhan 430064, China.; Research Center of Crop Stresses Resistance Technologies/ Engineering Research Centre of Ecology and Agricultural Use of Wetland, Ministry of Education, Yangtze University, Jingzhou 434025, China. Electronic address: wyzhang@yangtzeu.edu.cn.
Sweet potato (Ipomoea batatas L.) originated from South America; therefore, it is vulnerable to low temperature. Here, the evolutionary analysis of 22 cold-responsive genes in 35 plant species revealed that the identified MYC-type basic helix-loop-helix (bHLH) transcription factors exhibit diverse structures. We found that the number of bHLH gene family members was significantly lower than that of cold-tolerant species. We further systematically evaluated the gene structure, promoter analysis, synteny analysis, and expression pattern of 28 bHLH gene family members in sweet potato. The basic helix-loop-helix protein 116 (IbbHLH116) has the closest phylogeny to the AtICE1 protein of A. thaliana. However, the IbbHLH116 protein from cold-tolerant variety FS18 showed a 37.90% of sequence homology with AtICE1 protein. Subcellular localization analysis showed that IbbHLH116 is localized in the nucleus. The transcripts of IbbHLH116 were highly accumulated in cold-tolerant genotype FS18, particularly in new leaves and stems, compared to the cold-sensitive genotype NC1 under cold stress. Overexpression of IbbHLH116 in the wild type (Col-0) A. thaliana significantly enhanced cold tolerance in transgenic plants by regulating activities of oxidative protective enzymes, such as peroxidase (POD), superoxide dismutase (SOD), and the contents of malondialdehyde (MDA), proline and soluble proteins. Moreover, overexpression of IbbHLH116 in ice1 mutant A. thaliana fully rescued the cold-sensitive phenotype by promoting the expression of C-repeat binding factors 3 (CBF3). Overexpression of IbbHLH116 in the sweet potato callus also induced the expression of CBF3 under low temperature. These results imply that IbbHLH116 can perform the function of the ICE1 gene in conferring cold tolerance in sweet potato.
PMID: 35738441
J Plant Physiol , IF:3.549 , 2022 Sep , V276 : P153772 doi: 10.1016/j.jplph.2022.153772
Exogenous uniconazole enhances tolerance to chilling stress in mung beans (Vigna radiata L.) through cross talk among photosynthesis, antioxidant system, sucrose metabolism, and hormones.
College of Coastal Agriculture Sciences, Guangdong Ocean University, Zhanjiang, Guangdong, 524088, China; College of Agriculture, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang, 163319, China.; College of Coastal Agriculture Sciences, Guangdong Ocean University, Zhanjiang, Guangdong, 524088, China; Shenzhen Reseach Institute of Guangdong Ocean University, Shenzhen, Guangdong, 518108, China.; College of Coastal Agriculture Sciences, Guangdong Ocean University, Zhanjiang, Guangdong, 524088, China; Shenzhen Reseach Institute of Guangdong Ocean University, Shenzhen, Guangdong, 518108, China. Electronic address: zhengdf@gdou.edu.cn.; College of Agriculture, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang, 163319, China.
To monitor the role of exogenous uniconazole in mitigating chilling stress, this study investigated the effect of foliar spraying of 50 mg L(-1) uniconazole on the chilling (15 degrees C) tolerance of mung beans at the flowering stage. The results showed that uniconazole significantly enhanced the reactive oxygen species (ROS) scavenging ability of mung beans by increasing the superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX), glutathione reductase (GR) activities, the contents of ascorbic acid (AsA) and glutathione (GSH), and the transcription levels of SOD and POD under chilling stress. The uniconazole applications also drastically increased the net photosynthetic rate (Pn), maximum net photosynthetic rate (Pnmax), maximum quantum yield of PSII (Fv/Fm), and the expression levels of the corresponding photosynthetic genes PsbO, PsbP, PsbQ, PsbY, and Psb28. This, in turn, resulted in a higher sucrose content. Meanwhile, uniconazole increased the indole-3-acetic acid (IAA) content but reduced the gibberellin A3 (GA3) content under chilling stress. During the recovery period, the photosynthetic parameters and ROS of plants receiving uniconazole recovered faster, and the antioxidant activity and non-antioxidant contents were higher than in chilling-treated plants. Additionally, chilling stress markedly reduced the pod number per plant, grain number per plant, and 100-seed weight, whereas uniconazole significantly increased the grain weight per plant by 53.47% compared to the chilling treatment. These results strongly suggest that uniconazole can effectively protect mung beans from chilling stress damage by protecting the photosynthetic machinery and enhancing the antioxidant capacity to quench excessive ROS caused by chilling stress. These effects are closely relevant to chilling tolerance enhancement and yield improvement in mung beans.
PMID: 35872423
Biomed Res Int , IF:3.411 , 2022 , V2022 : P9247169 doi: 10.1155/2022/9247169
A De Novo Transcriptome Analysis Identifies Cold-Responsive Genes in the Seeds of Taxillus chinensis (DC.) Danser.
Guangxi Botanical Garden of Medicinal Plants, Nanning 530023, China.; Guangxi Key Laboratory for High-Quality Formation and Utilization of Dao-di Herbs, China.
Taxillus chinensis (DC.) Danser, a parasitic plant of the Loranthaceae family, grows by attacking other plants. It has a long history of being used in Chinese medicine to treat multiple chronic diseases. We previously observed that T. chinensis seeds are sensitive to cold. In this study, we performed transcriptome sequencing for T. chinensis seeds treated by cold (0 degrees C) for 0 h, 12 h, 24 h, and 36 h. TRINITY assembled 257,870 transcripts from 223,512 genes. The GC content and N50 were calculated as 42.29% and 1,368, respectively. Then, we identified 42,183 CDSs and 35,268 likely proteins in the assembled transcriptome, which contained 1,622 signal peptides and 6,795 transmembrane domains. Next, we identified 17,217 genes (FPKM > 5) and 2,333 differentially expressed genes (DEGs) in T. chinensis seeds under cold stress. The MAPK pathway, as an early cold response, was significantly enriched by the DEGs in the T. chinensis seeds after 24 h of cold treatment. Known cold-responsive genes encoding abscisic acid-associated, aquaporin, C-repeat binding factor (CBF), cold-regulated protein, heat shock protein, protein kinase, ribosomal protein, transcription factor (TF), zinc finger protein, and ubiquitin were deregulated in the T. chinensis seeds under cold stress. Notably, the upregulation of CBF gene might be the consequences of the downregulation of MYB and GATA TFs. Additionally, we identified that genes encoding CDC20, YLS9, EXORDIUM, and AUX1 and wound-responsive family protein might be related to novel mechanisms of T. chinensis seeds exposed to cold. This study is first to report the differential transcriptional induction in T. chinensis seeds under cold stress. It will improve our understanding of parasitic plants in response to cold and provide a valuable resource for future studies.
PMID: 35845948
J Appl Genet , IF:3.24 , 2022 Jul doi: 10.1007/s13353-022-00710-2
The genetic basis of cold tolerance in cucumber (Cucumis sativus L.)-the latest developments and perspectives.
Department of Plant Genetics Breeding and Biotechnology, Institute of Biology, Warsaw University of Life Sciences, Nowoursynowska 159, Warsaw, Poland.; Department of Plant Genetics Breeding and Biotechnology, Institute of Biology, Warsaw University of Life Sciences, Nowoursynowska 159, Warsaw, Poland. grzegorz_bartoszewski@sggw.edu.pl.
Cold stress is one of the main causes of yield losses in plant production in temperate climate areas. Cold stress slows down and even stops plant growth and development and causes injuries that may result in the plant's death. Cucumber (Cucumis sativus L.), an economically important vegetable, is sensitive to low temperatures, thus improving cold tolerance in cucumber would benefit cucumber producers, particularly those farming in temperate climates and higher altitude areas. So far, single cucumber accessions showing different degrees of cold tolerance have been identified, and genetic studies have revealed biparentally and maternally inherited genetic factors responsible for chilling tolerance. Paternally transmitted chilling tolerance has also been suggested. Quantitative trait loci (QTL) associated with seed germination ability at low temperature and seedling recovery from chilling have been described. Several transgenic attempts have been made to improve cold tolerance in cucumber. Despite numerous studies, the molecular mechanisms of cold tolerance in cucumber have still not been sufficiently elucidated. In this review, we summarise the results of research focused on understanding the genetic basis of cold tolerance in cucumber and their implications for cucumber breeding.
PMID: 35838983
Oecologia , IF:3.225 , 2022 Aug doi: 10.1007/s00442-022-05245-1
Acclimation to water stress improves tolerance to heat and freezing in a common alpine grass.
Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, 3125, Australia. eesumner@deakin.edu.au.; Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, 3125, Australia.; School of Biological Sciences, Monash University, Clayton, 3800, Australia.
Alpine plants in Australia are increasingly exposed to more frequent drought and heatwaves, with significant consequences for physiological stress responses. Acclimation is a critical feature that allows plants to improve tolerance to environmental extremes by directly altering their physiology or morphology. Yet it is unclear how plant performance, tolerance, and recovery are affected when heat and water stress co-occur, and whether prior exposure affects responses to subsequent climate extremes. We grew a common alpine grass species under high or low watering treatments for three weeks before exposure to either none, one, or two heat stress events. We determined photosynthetic heat and freezing tolerance (LT50, mean temperature causing 50% irreversible damage to photosystem II) and growth. Physiological adjustments to low watering, including more negative water potentials and reduced growth, were also characterised by improved tolerance to high and low-temperature extremes. Shifts to higher heat tolerance were also evident with increasing exposure to heat stress events, though freezing tolerance was not affected. Acclimation effects were mostly short-term, however; prior exposure to heat and/or water stress had little to no effect on growth and thermal tolerance following the six-week recovery period. We conclude that rapid acclimation to water and heat stress that co-occur during summer enhances the capacity of alpine plants to tolerate increasingly frequent temperature extremes.
PMID: 35974110
Funct Plant Biol , IF:3.101 , 2022 Jul doi: 10.1071/FP22043
Parental drought priming enhances tolerance to low temperature in wheat (Triticum aestivum) offspring.
Low temperature is one of the major environmental stresses that limit crop growth and grain yield in wheat (Triticum aestivum L.). Drought priming at the vegetative stage could enhance wheat tolerance to later cold stress; however, the transgenerational effects of drought priming on wheat offspring's cold stress tolerance remains unclear. Here, the low temperature responses of offspring were tested after the parental drought priming treatment at grain filling stage. The offspring plants from parental drought priming treatment had a higher abscisic acid (ABA) level and lower osmotic potential (Psio) than the control plants under cold conditions. Moreover, parental drought priming increased the antioxidant enzyme activities and decreased hydrogen peroxide (H2O2) accumulation in offspring. In comparison to control plants, parental drought priming plants had a higher ATP concentration and higher activities of ATPase and the enzymes involved in sucrose biosynthesis and starch metabolism. The results indicated that parental drought priming induced low temperature tolerance in offspring by regulating endogenous ABA levels and maintaining the redox homeostasis and the balance of carbohydrate metabolism, which provided a potential approach for cold resistant cultivation in wheat.
PMID: 35871526
Funct Plant Biol , IF:3.101 , 2022 Jul doi: 10.1071/FP21290
Identifying conserved genes involved in crop tolerance to cold stress.
Low temperature is a limiting factor for crop productivity in tropical and subtropical climates. Cold stress response in plants involves perceiving and relaying the signal through a transcriptional cascade composed of different transduction components, resulting in altered gene activity. We performed a meta-analysis of four previously published datasets of cold-tolerant and cold-sensitive crops to better understand the gene regulatory networks and identify key genes involved in cold stress tolerance conserved across phylogenetically distant species. Re-analysing the raw data with the same bioinformatics pipeline, we identified common cold tolerance-related genes. We found 236 and 242 commonly regulated genes in sensitive and tolerant genotypes, respectively. Gene enrichment analysis showed that protein modifications, hormone metabolism, cell wall, and secondary metabolism are the most conserved pathways involved in cold tolerance. Upregulation of the abiotic stress (heat and drought/salt) related genes [heat shock N-terminal domain-containing protein, 15.7kDa class I-related small heat shock protein-like, DNAJ heat shock N-terminal domain-containing protein, and HYP1 (HYPOTHETICAL PROTEIN 1)] in sensitive genotypes and downregulation of the abiotic stress (heat and drought/salt) related genes (zinc ion binding and pollen Ole e 1 allergen and extensin family protein) in tolerant genotypes was observed across the species. Almost all development-related genes were upregulated in tolerant and downregulated in sensitive genotypes. Moreover, protein-protein network analysis identified highly interacting proteins linked to cold tolerance. Mapping of abiotic stress-related genes on analysed species genomes provided information that could be essential to developing molecular markers for breeding and building up genetic improvement strategies using CRISPR/Cas9 technologies.
PMID: 35785800
Funct Plant Biol , IF:3.101 , 2022 Aug , V49 (9) : P832-843 doi: 10.1071/FP22005
Feasibility of using melatonin content in pepper (Capsicum annuum) seeds as a physiological marker of chilling stress tolerance.
Department of Horticulture, Kahramanmaras Sutcu Imam University, Kahramanmaras, Turkey.; Department of Plant Ecophysiology, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland.; Department of Horticulture, Yozgat Bozok University, Yozgat, Turkey.
The presence of melatonin, a known animal hormone, has been confirmed in many evolutionary distant organisms, including higher plants. It is known that melatonin increases tolerance to stress factors as a wide spectrum antioxidant. Tolerant genotypes have generally higher melatonin content than sensitive ones, and exposure to stressful conditions is known to increase endogenous melatonin levels. However, endogenous melatonin levels in seeds have never been used to select genotypes tolerant to abiotic stresses. Thus, in this study, the existence of possible relationship between seed melatonin levels of 28 pepper (Capsicum annuum L.) genotypes and their germination and emergence performance under chilling conditions (15 degrees C) was investigated. The results indicated that these parameters were much better for pepper genotypes with higher seed melatonin contents while those having less than 2ngg-1 additionally exhibited elevated levels of MDA and H2 O2 but lower antioxidant enzyme activities. Thus, a positive relationship between seed melatonin content and chilling stress tolerance has been shown, suggesting a possible use of endogenous melatonin levels as a criterion in selecting chilling stress tolerant varieties. To save considerable time, money and labour, it is recommended that genotypes with lower melatonin contents are excluded from breeding programmes that aim to develop new stress tolerant genotypes.
PMID: 35701365
PeerJ , IF:2.984 , 2022 , V10 : Pe13746 doi: 10.7717/peerj.13746
Genome-wide identification and expression pattern analysis of lipoxygenase gene family in turnip (Brassica rapa L. subsp. rapa).
College of Horticulture, Xinjiang Agricultural University, Urumqi, Xinjiang, China.
Turnip (Brassica rapa L. subsp. rapa) is an important crop with edible and medicinal values, and various stresses, especially salt stress and drought stress, seriously threaten the yield of turnips. LOXs play important roles in regulating plant growth and development, signal transduction, and biotic and abiotic stress responses through secondary metabolites produced by the oxylipin metabolic pathway, and although the turnip genome has been published, however, the role of LOX family genes in various abiotic stress responses has not been systematically studied in turnips. In this study, a total of 15 LOX genes (BrrLOX) were identified in turnip, distributed on six chromosomes. Phylogenetic tree analysis classified these LOX genes into two classes: three 9-LOX proteins and 12 13-LOX type II proteins. Gene duplication analysis showed that tandem and segmental duplication were the main pathways for the expansion of the BrrLOX gene family. The Ka and Ks values of the duplicated genes indicate that the BrrLOX gene underwent strong purifying selection. Further analysis of the cis-acting elements of the promoters suggested that the expression of the BrrLOX gene may be influenced by stress and phytohormones. Transcriptome data analysis showed that 13 BrrLOX genes were expressed at one or more stages of turnip tuber development, suggesting that LOX genes may be involved in the formation of turnip fleshy roots. The qRT-PCR analysis showed that four stresses (salt stress, drought stress, cold stress, and heat stress) and three hormone treatments (methyl jasmonate, salicylic acid, and abscisic acid) affected the expression levels of BrrLOX genes and that different BrrLOX genes responded differently to these stresses. In addition, weighted gene co-expression network analysis (WGCNA) of BrrLOX revealed seven co-expression modules, and the genes in these co-expression modules are collectively involved in plant growth and development and stress response processes. Thus, our results provide valuable information for the functional identification and regulatory mechanisms of BrrLOX in turnip growth and development and stress response.
PMID: 35898937
Mol Biol Rep , IF:2.316 , 2022 Aug , V49 (8) : P7347-7358 doi: 10.1007/s11033-022-07527-6
Expression of a Pennisetum glaucum gene DREB2A confers enhanced heat, drought and salinity tolerance in transgenic Arabidopsis.
National Institute for Plant Biotechnology, Pusa Campus, New Delhi, India.; PG School, ICAR-Indian Agricultural Research Institute, Pusa Campus, New Delhi, 110012, India.; National Institute for Plant Biotechnology, Pusa Campus, New Delhi, India. jasdeep_kaur64@yahoo.co.in.; PG School, ICAR-Indian Agricultural Research Institute, Pusa Campus, New Delhi, 110012, India. jasdeep_kaur64@yahoo.co.in.
BACKGROUND: Pearl millet (Pennisetum glaucum) is an essential cereal crop, whose growth and yield are not impacted by abiotic stresses, such as drought, heat, and cold. The DREB transcription factors (TF) are some of the largest groups of TFs in plants and play varied roles in plant stress response and signal transduction. METHODS AND RESULTS: In the present study, PgDREB2A gene encoding a DREB transcription factor in pearl millet was functionally characterized in Arabidopsis. DREB2A proteins contain a conserved domain that binds toethylene responsive element binding factors. Three different T1 transgenic lines overexpressing PgDREB2A gene were identified by Southern blot. Quantitative real-time polymerase chain reaction exhibited that PgDREB2A could be induced under drought conditions. As compared with the control, PgDREB2A overexpressing transgenic Arabidopsis showed increased rate of seed germination and root growth in transgenic lines under higher concentrations of mannitol, NaCl, ABA, heat and cold stress. Additionally, PgDREB2A transgenic lines showed enhanced durability after rehydration and tolerance to drought and salt stress was augmented with increased proline and reduced MDA build-up and diminishing water loss. CONCLUSIONS: Results from this study suggested that PgDREB2A as a transcription factor may improve endurance to various abiotic stresses and can be employed for developing crops tolerant to abiotic stresses.
PMID: 35666421