细胞分裂素介导的拟南芥对灰霉菌的抗性反应机制

植物形成了复杂而精细的防御反应网络以抵御环境中各种病原微生物的侵袭。细胞分裂素（CK）是一类重要的植物激素，在调控植物生长发育及抵抗各种环境胁迫中发挥着重要的作用，但其参与的植物对腐生型病原菌防御机制尚不清楚。本项目拟以拟南芥和腐生型病原菌灰霉菌（Botrytis cinerea）为研究对象，1）通过qPCR、激素含量测定等方法检测CK对灰霉菌的响应；2）利用外源CK预处理的野生型植株（WT）和CK突变体对灰霉菌的抗性变化鉴定CK对灰霉菌抗性的影响；3）通过RNA-seq和激素含量测定等方法检测内源CK信号被抑制后，灰霉菌诱导的JA/ET、SA信号途径发生的变化，利分析外源MeJA或SA预处理的WT和JA/ET/SA突变体中灰霉菌诱导的CK信号的变化，以解析在对灰霉菌的抗性反应中CK与植物重要防御机制JA/ET、SA的交叉反应。本研究将为阐明植物对腐生型病原菌抗性反应的分子机制奠定基础。

To respond to pathogen attack, selection and associated evolution has led to the creation of plant immune system that is a highly effective and inducible defense system. Cytokinins (CKs) are essential plant hormones that control almost every aspect of plant growth, development and also function in mediating plant defense against a lot of enviromental stresses. However, the mechanism of CKs in plant defense against necrotrophic pathogen is still largely unknown. In this study we will use Arabidopsis and necrotrophic pathogen Botytis cinerea as subject investigated. 1) The changes of CK levels upon B. cinerea infection will be analyzed by qRT-PCR and the quantification of CK concentration in plants. 2) The effect of exogenous CK application or endogenous CK deficiency on host defense to B. cinerea will be confirmed. 3) To reveal the interactions between CK and JA/ET/SA signal pathway regulating plant immune responses to B. cinerea, comparative gene expression and JA/ET/SA concentration analysis between wild type (WT) and CK mutants upon B. cinerea infection will be performed; corresponding comparative analysis will be done for CK in exogenous MeJA or SA treated WT and in JA/ET/SA deficient mutants. These results will provide more insights into the role of CK in modulating host stress responses towards necrotroph B. cinerea.