番茄质外体H2O2与MAPK互作在冷驯化提高交叉抗性中的作用机制研究

Both NADPH oxidase-mediated apoplastic H2O2 and mitogen-activated protein kinase (MAPK) play pivotal roles in plant response to multiple biotic and abiotic stresses. However, the crosstalk between them in induction of cross tolerance to abiotic stresses remains to be elucidated. In this project, cold acclimation-induced responses and tolerance in tomato plants to aboitic stresses (chilling, heat, paraquat, drought, et al.) will be analyzed. To further elucidate the crosstalk mechanism between RBOH and MAPK, the changes in H2O2 accumulation, activity of NADPH oxidase, transcripts of RBOH1/2 and MAPK1/2/3, activation of MAPK1/2/3, and stress responsive and defense related genes will be investigated in both tomato RBOH1/2 and MAPK1/2/3-silenced plants after cold acclimation pretreatment and subsequent abiotic stresses treatments. Meanwhile, tomato gene expression microarray and yeast two-hybrid system were used to isolate the key genes and proteins downstream of RBOH-MAPK. These results will not only give insight into the mechanism of crosstalk between RBOH1/2 and MAPK1/2/3 in cold acclimation-induced tolerance in tomato crops, but also supply theoretical basis and technical guidance for vegetable production.

RBOH (respiratory burst oxidase homologs)编码的质膜NADPH氧化酶产生的H2O2和促分裂原活化蛋白激酶（MAPK）在植物响应生物与非生物逆境胁迫的信号转导中起重要作用，然而，两者之间的互作机制及其在植物驯化提高抗性中的作用还尚不清楚。本项目以设施主栽作物番茄为材料，研究不同温度和时间的冷驯化对植株低温、高温、干旱和光氧化胁迫抗性、质膜NADPH氧化酶、H2O2和MAPK信号通路关键元件的影响；通过VIGS沉默番茄RBOH1/2和MAPK1/2/3这两类在抗逆反应中发挥关键作用的基因，并结合番茄基因芯片和酵母双杂交等技术，揭示RBOH1/2-MAPK1/2/3互作在抗逆信号转导中的作用及其下游调控基因和蛋白，建立冷驯化-RBOH1/2- MAPK1/2/3 -抗逆反应-交叉抗性的作用模型，为利用驯化机制服务蔬菜生产提供理论依据和技术指导。

针对冷驯化提高番茄交叉抗性的主题，我们研究了冷驯化过程中RBOH1介导产生的质外体过氧化氢（H2O2）和促分裂原活化蛋白激酶1/2（MPK1/2）蛋白的互作机制及其在提高番茄交叉抗性中的作用；明确了冷驯化刺激硝酸还原酶（NR）依赖的一氧化氮（NO）信号和MPK1/2信号互作进而激发下游CBF（C-repeat Binding Factor）途径来实现番茄冷抗性的提高；通过发掘上游的钙依赖蛋白激酶（CPKs）家族基因，发现了CPK27在冷驯化过程中的关键作用；具体阐明了H2O2-NO-MPK1/2与CPK27在冷驯化提高冷抗性中的关系；全面解析了脱落酸（ABA）积累与以上信号分子之间互作提高番茄抗逆性的分子机制。发表标注SCI论文10篇，获得国家科技进步二等奖1项。