水稻热激转录因子HsfA2b调控非生物胁迫抗性的功能分析OA北大核心CSTPCD

[Objective]Rice is often affected by various abiotic stresses during growth and development,which severely restricts rice yield.Heat shock transcription factors(HSFs),as an important element of resistance to abiotic stresses in plant,can enhance plant resistance to abiotic stresses by regulating the expressions of a series of stress related genes.This study aims to investigate the function and mechanism of rice heat shock transcription factor OsHsfA2b regulating abiotic stresses,which may provide excellent gene resource and theoretical support for cultivating new rice varieties with stress resistance.[Method]We constructed OsHsfA2b-overexpressed and RNAi rice transgenic plants,then their seedlings were treated with high temperature,low temperature,drought,and high salt,respectively,and their phenotypes were observed and survival rates were counted.The detection of reactive oxygen species(ROS)deposition by DAB staining,and expression levels of antioxidant pathway related genes OsSOD and OsCAT with RT-qPCR after abiotic stress treatment,aiming to analyze the regulatory effect of OsHsfA2b on the antioxidant pathway.[Result]The rice HSF gene OsHsfA2b was induced significantly by abiotic stress conditions,such as high temperature,low temperature,drought,and high salt.Compared with the wild-type plants,OsHsfA2b-overexpressed transgenic plants significantly enhanced the resistance to abiotic stresses,as well as survival rate,and less damage.On the contrary,both resistance and survival rate of OsHsfA2b-RNAi plants to abiotic stresses decreased,and the plants were severely damaged.Moreover,the ROS deposition in OsHsfA2b-overexpressed plants decreased compared with NPB and RNAi plants under abiotic stress.Correspondingly,OsHsfA2b induced the expressions of antioxidant pathway related genes OsSOD and OsCAT,suggesting that OsHsfA2b suppressed ROS accumulation to reduce its damage caused by abiotic stress induction.[Conclusion]The above results indicate that OsHsfA2b is induced by abiotic stresses and positively regulates rice resistance to abiotic stresses through antioxidant pathways,and it is an excellent gene resource for rice stress-resistance breeding.