中间锦鸡儿WRKY转录因子参与非生物胁迫的分子机制

WRKY transcription factors, one of the largest families of transcriptional regulators in plants, play important roles in plant development and various stress responses. Caragana intermedia, a native desert perennial shrub belonging to the Leguminosae family, is proved to be strongly resistant to stress, and is a good material for screening genes of resistance. Based on previous transcriptome data of C. intermedia under drought stress performed in our lab, we obtained 28 CiWRKYs with completely open reading frame, and analyzed their respossive to five different abiotic stresses. Through functional studies 2 of the CiWRKYs which respond to different adversities, it is found that the different functions displayed in those CiWRKYs compared with the homologous genes of Arabidopsis. The aim of this study is to explore more WRKY genes that have differential function with Arabidopsis homologues in C. intermedia. In this study, 3-7 genes will be selected from the other 26 CiWRKYs for function identification. Through over expression of CiWRKYs and their Arabidopsis homologues in C. intermedia and A. thaliana, the function of WRKYs under different abiotic stress conditions will be analyzed. The molecular regulatory network for 1-2 CiWRKYs will be constructed to elucidate the similarities and differences of the homologous genes between Arabidopsis and C. intermedia involved in stress resistance, and to evaluate their potential application in transgenic plants. The results will lay the foundation and provide gene resources for screening and cultivating of new varieties of forest and forage with strong stress resistant.

WRKY转录因子是植物最大的转录调节子家族之一，参与了许多植物生物学的进程。中间锦鸡儿是豆科锦鸡儿属植物，耐逆性强，是挖掘抗逆基因的优良物种。在前期中间锦鸡儿干旱转录组研究基础上，我们获得了28个CiWRKYs基因并进行了逆境响应表达谱分析，通过对其中2个CiWRKYs功能研究发现其与拟南芥同源基因可能具有不同的功能。本项目旨在挖掘更多的、与拟南芥同源基因功能具有差异的CiWRKY基因。基于此，拟根据逆境响应表达谱继续从中挑选3-7个CiWRKYs作为候选基因，通过在模式植物拟南芥和中间锦鸡儿毛状根中表达，比较分析候选基因在干旱等逆境胁迫中的作用。选取1-2个重要的CiWRKYs构建分子调控网络，明确其与拟南芥同源基因参与逆境胁迫功能的异同，同时评价CiWRKY转入植物后的抗逆能力及可能的应用前景。通过本研究为筛选和培育抗逆能力强的林木和牧草新品种提供新的基因资源。

WRKY转录因子是植物最大的转录调节子家族之一，参与了许多植物生物学的进程。中间锦鸡儿是豆科锦鸡儿属植物，耐逆性强，是挖掘抗逆基因的优良物种。本课题组对干旱处理的中间锦鸡儿进行了转录组测序，获得了大量抗逆相关基因。通过克隆中间锦鸡儿抗非生物胁迫关键的WRKY基因，在拟南芥或中间锦鸡儿毛状根中进行过表达或敲除，研究其生理功能，进而探究其参与逆境胁迫环境的分子机制，评价其转入植物后的抗逆能力及可能的应用前景，为筛选和培育抗逆能力强的林木和牧草新品种提供新的基因资源。.项目按申请书和计划任务书实施，筛选克隆了CiWRKY12、CiWRKY15、CiWRKY17、CiWRKY23、CiWRKY30、CiWRKY36、CiWRKY41-1、CiWRKY48、CiWRKY50、CiWRKY57等10个中间锦鸡儿响应非生物胁迫的关键WRKY转录因子的编码基因，进行了拟南芥遗传转化，并开展了响应干旱、冷、高盐等非生物胁迫和生长发育调控等相关的生物学研究。发现CiWRKY36可能在光及激素信号通路中发挥重要作用，可能是暗形态建成的正调控因子；CiWRKY17基因过表达后加速拟南芥发育和衰老，可能参与了生长发育进程调节。相关研究发表学术论文7篇，其中SCI论文2篇。同时建立中间锦鸡儿毛状根遗传转化体系并进行了优化，相关技术申请国家发明专利2项，其中授权1项。