Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drou...Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drought and osmotic stresses in apple(Malus×domestica Borkh.)remain unclear.Here,we functionally characterized the apple GroupⅢWRKY gene MdWRKY115.qRT-PCR analysis showed that MdWRKY115 expression was up-regulated by drought and osmotic stresses.GUS activity analysis revealed that the promoter activity of MdWRKY115 was enhanced under osmotic stress.Subcellular localization and transactivation assays indicated that MdWRKY115 was localized to the nucleus and had a transcriptional activity domain at the N-terminal region.Transgenic analysis revealed that the overexpression of MdWRKY115 in Arabidopsis plants and in apple callus markedly enhanced their tolerance to drought and osmotic stresses.DNA affinity purification sequencing showed that MdWRKY115 binds to the promoter of the stress-related gene MdRD22.This binding was further verified by an electrophoretic mobility shift assay.Collectively,these findings suggest that MdWRKY115 is an important regulator of osmotic and drought stress tolerance in apple.展开更多
High temperature(HT)is one of the most important environmental stress factors and seriously threatens plant growth,development,and production.VQ motif-containing proteins are transcriptional regulators that have been ...High temperature(HT)is one of the most important environmental stress factors and seriously threatens plant growth,development,and production.VQ motif-containing proteins are transcriptional regulators that have been reported to regulate plant growth and developmental processes,including responses to biotic and abiotic stresses.However,the relationships between VQ motif-containing proteins and HT stress have not been studied in depth in plants.In this study,transgenic apple(Malus domestica)plants overexpressing the apple VQ motif-containing protein-coding gene(MdVQ37)were exposed to HT stress,and the transgenic lines exhibited a heat-sensitive phenotype.In addition,physiological and biochemical studies revealed that,compared with WT plants,transgenic lines had lower enzymatic activity and photosynthetic capacity and lower amounts of nonenzymatic antioxidant system metabolites under HT stress.Transcriptome analysis revealed 1379 genes whose expression differed between the transgenic lines and WT plants.GO and KEGG pathway analyses showed that transcription factor activity and plant hormone signaling pathways were differentially influenced and enriched in the transgenic lines.Salicylic acid(SA)content analysis indicated that overexpression of MdVQ37 reduced the content of endogenous SA by regulating the expression of SA catabolism-related genes,which ultimately resulted in disruption of the SA-dependent signaling pathway under HT stress.The application of SA slightly increased the survival rate of the transgenic lines under HT stress.Taken together,our results indicate that apple MdVQ37 has a regulatory function in basal thermotolerance by modulating the activity of transcription factors and SA homeostasis.Overall,this study provides novel insights that improve our understanding of the various functions of VQ motif-containing proteins.展开更多
基金supported by grants from the Natural Science Foundation of Hebei Province(Grant No.C2022204086)the Hebei Apple Innovation Team of Modern Agricultural Industry Technology System(Grant No.HBCT2021100211)the National Natural Science Foundation of China(Grant No.32072524).
文摘Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drought and osmotic stresses in apple(Malus×domestica Borkh.)remain unclear.Here,we functionally characterized the apple GroupⅢWRKY gene MdWRKY115.qRT-PCR analysis showed that MdWRKY115 expression was up-regulated by drought and osmotic stresses.GUS activity analysis revealed that the promoter activity of MdWRKY115 was enhanced under osmotic stress.Subcellular localization and transactivation assays indicated that MdWRKY115 was localized to the nucleus and had a transcriptional activity domain at the N-terminal region.Transgenic analysis revealed that the overexpression of MdWRKY115 in Arabidopsis plants and in apple callus markedly enhanced their tolerance to drought and osmotic stresses.DNA affinity purification sequencing showed that MdWRKY115 binds to the promoter of the stress-related gene MdRD22.This binding was further verified by an electrophoretic mobility shift assay.Collectively,these findings suggest that MdWRKY115 is an important regulator of osmotic and drought stress tolerance in apple.
基金This work was supported by the National Key Research and Development Program of China(2018YFD1000303)earmarked funds for the China Agriculture Research System(CARS-27)the National Natural Science Foundation of China(31401852 and 31701894)。
文摘High temperature(HT)is one of the most important environmental stress factors and seriously threatens plant growth,development,and production.VQ motif-containing proteins are transcriptional regulators that have been reported to regulate plant growth and developmental processes,including responses to biotic and abiotic stresses.However,the relationships between VQ motif-containing proteins and HT stress have not been studied in depth in plants.In this study,transgenic apple(Malus domestica)plants overexpressing the apple VQ motif-containing protein-coding gene(MdVQ37)were exposed to HT stress,and the transgenic lines exhibited a heat-sensitive phenotype.In addition,physiological and biochemical studies revealed that,compared with WT plants,transgenic lines had lower enzymatic activity and photosynthetic capacity and lower amounts of nonenzymatic antioxidant system metabolites under HT stress.Transcriptome analysis revealed 1379 genes whose expression differed between the transgenic lines and WT plants.GO and KEGG pathway analyses showed that transcription factor activity and plant hormone signaling pathways were differentially influenced and enriched in the transgenic lines.Salicylic acid(SA)content analysis indicated that overexpression of MdVQ37 reduced the content of endogenous SA by regulating the expression of SA catabolism-related genes,which ultimately resulted in disruption of the SA-dependent signaling pathway under HT stress.The application of SA slightly increased the survival rate of the transgenic lines under HT stress.Taken together,our results indicate that apple MdVQ37 has a regulatory function in basal thermotolerance by modulating the activity of transcription factors and SA homeostasis.Overall,this study provides novel insights that improve our understanding of the various functions of VQ motif-containing proteins.
