The TSJT1 protein belongs to the class-II glutamine amidotransferase(GATase)superfamily.Research on the functions and underlying mechanisms of TSJT1 in plants is limited.In this study,the abscisic acid(ABA)-inducible ...The TSJT1 protein belongs to the class-II glutamine amidotransferase(GATase)superfamily.Research on the functions and underlying mechanisms of TSJT1 in plants is limited.In this study,the abscisic acid(ABA)-inducible gene IbTSJT1 was isolated from drought-tolerant sweetpotato line Xushu 55-2.Its expression was strongly induced by PEG6000 and ABA.The IbTSJT1 protein was localized in the nucleus and cell membrane.IbTSJT1-overexpressing sweetpotato plants exhibited significantly enhanced drought tolerance.Their ABA and proline contents and superoxide dismutase(SOD)and peroxidase(POD)activities were increased,and their reactive oxygen species(ROS)scavenging-related genes were upregulated under drought stress.The stomatal aperture assay confirmed that the IbTSJT1-overexpressing plants had greater sensitivity to ABA.The results of yeast onehybrid(Y1H)assay,electrophoretic mobility shift assay(EMSA),luciferase reporter assay and ChIP-qPCR assay indicated that IbABF2 can directly bind to the cis-acting ABA-responsive element(ABRE)in the IbTSJT1 promoter to activate the expression of IbTSJT1.These findings suggest that IbTSJT1 mediates ABA-dependent drought stress responses and enhances drought tolerance by inducing stomatal closure and activating the ROS scavenging system in transgenic sweetpotato.Our study provides a novel gene for improving drought tolerance in sweetpotato and other plants.展开更多
基金supported by the earmarked fund for CARS-10-Sweetpotato and the Beijing Food Crops Innovation Consortium Program,China(BJLSTD03)。
文摘The TSJT1 protein belongs to the class-II glutamine amidotransferase(GATase)superfamily.Research on the functions and underlying mechanisms of TSJT1 in plants is limited.In this study,the abscisic acid(ABA)-inducible gene IbTSJT1 was isolated from drought-tolerant sweetpotato line Xushu 55-2.Its expression was strongly induced by PEG6000 and ABA.The IbTSJT1 protein was localized in the nucleus and cell membrane.IbTSJT1-overexpressing sweetpotato plants exhibited significantly enhanced drought tolerance.Their ABA and proline contents and superoxide dismutase(SOD)and peroxidase(POD)activities were increased,and their reactive oxygen species(ROS)scavenging-related genes were upregulated under drought stress.The stomatal aperture assay confirmed that the IbTSJT1-overexpressing plants had greater sensitivity to ABA.The results of yeast onehybrid(Y1H)assay,electrophoretic mobility shift assay(EMSA),luciferase reporter assay and ChIP-qPCR assay indicated that IbABF2 can directly bind to the cis-acting ABA-responsive element(ABRE)in the IbTSJT1 promoter to activate the expression of IbTSJT1.These findings suggest that IbTSJT1 mediates ABA-dependent drought stress responses and enhances drought tolerance by inducing stomatal closure and activating the ROS scavenging system in transgenic sweetpotato.Our study provides a novel gene for improving drought tolerance in sweetpotato and other plants.
