一个拟南芥锌指蛋白及其互作转录因子在植物与病原细菌互作中的调控网络解析

Many zinc finger proteins (ZFPs) have been confirmed to be involved in plant development and abiotic stress responses, but information about the biological role of specific ZFP in plant-pathogen interaction and in the phytohormone interaction is limited. Previously, we found that the transcript levels of cysteine2/histidine2 (C2H2)-type transcription factor ZINC FINGER OF ARABIDOPSIS THALIANA 6 (ZAT6) were largely induced by various stress treatments, and AtZAT6 positively modulated plant resistance to bacterial pathogen infection. Based on yeast two-hybrid screen, we identified 18 transcription factors as ZAT6-interacting proteins, and verified the association of ZAT6 with some of them in vivo using bimolecular fluorescence complementation (BiFC) analysis. Additionally, we are identifying the direct targets of AtZAT6 through Chromatin Immunoprecipitation (ChIP)-seq. Furthermore, we will investigating the involvement of these genes such as AtIAA17 in plant-pathogen interaction and the interacted proteins and target genes of these genes, as well as the signaling pathway of AtZAT6-formed transcriptional modules and interacting complex through molecular genetic experiments. Taken together, we will reveal the regulatory mechanisms underlying AtZAT6-mediated plant-pathogen interaction, as well as the related phytohormone interaction. Based on these results, gene homologs from agricultural plants will be cloned and functionally analyzed in order to increase stress resistance through transgenic approach.

锌指蛋白作为一类大家族的转录因子，在植物非生物胁迫应答中非常重要，然而它们是否在植物免疫应答中的信号通路还不清楚。前期工作中，申请人分离了一个受各种胁迫诱导的拟南芥锌指结构转录因子AtZAT6，并发现其正调控植物的抗病性。基于酵母双杂交系统，我们获得了18个与AtZAT6相互作用的转录因子，并对部分感兴趣的蛋白互作进行了验证；同时，基于染色质免疫共沉淀的测序技术，我们正在分离AtZAT6直接调控的下游基因和顺式作用元件。下一步，我们将研究候选基因在植物免疫应答中的功能，及对下游基因的影响；同时通过原生质体转化系统研究候选蛋白对相应信号传导途径的影响，了解其这些蛋白复合体和转录因子-下游基因在协同参与植物抗病信号传导中的功能。通过以上研究，我们将探讨AtZAT6及其互作蛋白等信号途径参与植物免疫抗性的分子网络。同时，相关作用因子的鉴定也为后期通过基因工程提高植物对逆境胁迫的抗性提供基础。

拟南芥锌指结构转录因子ZAT6在植物非生物胁迫应答和抗病反应中非常重要，然而其信号通路还有待进一步鉴定。在本项目中，我们鉴定出ZAT6的上游调控因素（褪黑素和生长素）和下游基因（花青素合成途径中相关基因和植物抗病相关基因），从上下游关系上鉴定出ZAT6介导的花青素合成和抗病反应。另外，我们筛选并验证ZAT6与两个转录因子（IAA17和IDD15）互作，结合众多转录因子参与的激素互作调控分析（ZAT6 & IDD15-YUC2启动子-生长素合成，ZAT6 & IAA17-生长素信号），阐明了ZAT6及其互作转录因子参与植物胁迫信号的分子机理。同时获得抗病性提高的转基因植株，结合相关作用因子的鉴定，为后期通过基因工程提高植物对逆境胁迫的抗性提供了基础。