转录因子BZR1与表观遗传因子HD2C互作调控番茄低温抗性的机制

冬春季节设施番茄频繁遭受低温冷害。油菜素内酯（BR）提高番茄耐冷性与脱落酸（ABA）积累增加有关，但具体机制还有待于进一步研究。我们前期工作发现，BR信号下游的转录因子BZR1在低温抗性中具有重要作用，BZR1能与表观遗传因子组蛋白去乙酰化酶HD2C发生互作，而缺失HD2C导致ABA代谢紊乱及低温抗性下降。因此，BZR1可能通过HD2C调控ABA代谢基因的乙酰化提高番茄耐冷性。申请项目研究BZR1和HD2C在调控番茄耐冷性中的作用，并阐明两者的互作关系；挖掘BZR1和HD2C调控的低温抗性关键基因并阐明其功能；明确BZR1和HD2C对ABA代谢基因的组蛋白乙酰化调控。项目的实施有助于阐明BR调控番茄耐冷性的机制，为实现设施亚适宜环境下番茄生产的提质增效提供理论依据。

Tomato plants frequently suffer chilling stress in the greenhouse during spring-winter period. Brassinosteroid (BR)-induced chilling tolerance has been shown to be associated with an increase in the accumulation of abscisic acid (ABA). However, the exact mechanism remains to be further studied. Our previous work found that BZR1, a transcription factor downstream of BR signaling, played an important role in chilling tolerance in tomato. BZR1 interacted with the epigenetic regulator, histone deacetylase HD2C. Silencing of HD2C led to disorders of ABA metabolism and chilling sensitivity. Therefore, BZR1 may regulate histone acetylation of ABA metabolic genes through HD2C to improve tomato chilling tolerance. In this project, we aim to reveal the functions of BZR1 and HD2C in the regulation of tomato chilling tolerance, identify the critical chilling response genes regulated by BZR1 and HD2C and elucidate their functions, and finally dissect the regulation of histone acetylation of ABA metabolic genes by BZR1 and HD2C. The implementation of the project will help elucidate the mechanism by which BR regulates the chilling tolerance of tomato and provide a theoretical basis for the improvement of tomato production efficiency under sub-optimal environmental conditions in the greenhouse.