一个RNA结合蛋白MHZ9通过翻译调控介导乙烯信号转导的机制研究

乙烯在水稻生长发育及环境适应性上发挥着重要作用。乙烯信号研究多集中于拟南芥，水稻乙烯信号转导机制与双子叶模式植物拟南芥相比既有保守性又存在特殊性。拟南芥发现EIN2-C能进入P-body抑制EBF1/2 mRNA翻译，而EBF1/2 mRNA的识别与翻译抑制机理以及全基因组水平的翻译调控规律仍需深入研究。本项目围绕水稻乙烯反应突变体mhz9展开，MHZ9是一个具有RNA结合活性的GYF蛋白，与OsEIN2-C形成复合体结合OsEBF1/2 mRNA进而抑制翻译。拟通过进一步的遗传学、分子生物学分析揭示MHZ9在乙烯信号翻译调控中的作用机制。并期望通过RNA-IP seq、CLIP-seq和Ribo-seq联合分析，解析水稻乙烯信号转导中的全基因组水平翻译调控规律。本项目将鉴定一个新的乙烯信号调控组分，解析翻译层面的调控机制，为作物的分子设计育种提供基因资源和改良依据。

Ethylene plays a considerable role in rice growth, development, and environmental adaptability. The ethylene signaling pathway has been established in Arabidopsis. However, both conserved and distinct mechanisms of the ethylene signaling pathway have been discovered in rice compared to Arabidopsis. In Arabidopsis, EIN2-C translocates into P-body to inhibit the translation of EBF1/2 mRNA. There are several questions still to be answered: How does EIN2-C recognize EBF1/2 mRNA, and what is the specific mechanism of translation inhibition. What are the genome-wide translation regulation patterns. This project revolves around the ethylene response mutant mhz9. MHZ9 is a glycine-tyrosine-phenylalanine (GYF) domain-containing RNA-binding protein. MHZ9 and OsEIN2-C interact to form a complex that directly binds to OsEBF1/2 mRNA 3′UTR for translation inhibition. Further genetics, biochemistry and molecular biology studies in this project should reveal the mechanism by which MHZ9 regulates translation in ethylene signaling. Together with the RNA-IP seq, CLIP-seq, and Ribo-seq in further studies will uncover the genome-wide translational regulation patterns in ethylene signaling. The project should provide genetic resources and theory for agronomic traits improvement by characterization of a novel regulatory component and revealing the underlying mechanisms of translation regulation in the ethylene signaling pathway.