拟南芥E3泛素连接酶ATL5调控种子寿命的作用机制研究

种子寿命是生态学和农业上具有双重意义的性状。寻找调控种子寿命关键基因，特别是调节基因，并阐明其作用机制，对于国家粮食安全与种质资源保存具有重要意义。我们前期发现，拟南芥ATL5（Arabidopsis Tóxicos en Levadura 5）突变后种子寿命显著降低。ATL5是植物特有的RING型E3泛素连接酶家族成员，其介导的蛋白质选择性降解是生物体内最精细的调控体系之一。由于干种子基因组绝大部分基因在种子发育后期已转录成储存mRNA，加强对种子贮藏与萌发过程种子寿命相关的转录后调控机制研究就显得尤为必要。为此，本项目拟采用多学科结合的方法，确定ATL5在调控种子寿命中的功能，筛选ATL5作用的底物蛋白，解析ATL5对底物蛋白稳定性调节与种子寿命的关系，阐明ATL5介导的种子寿命翻译后调控新机制。理论上将拓展人们对种子寿命调控机理的认识，实践上为提高种子耐贮性提供新的关键基因。

Seed longevity is an important trait from both ecological and agricultural perspectives. Mining and clarifying key genes especially regulatory genes, in controlling seed longevity and elucidating the molecular mechanism is of great significance to both the safe grain production and plant germplasm conservation. We previously found that disruption of Arabidopsis ATL5 (Arabidopsis Tóxicos en Levadura) showed seed ageing phenotype. ATL5 is a number of plant-specific RING-type E3 ligase family. The ubiquitin-proteasome pathway is one of the most important regulatory mechanisms for protein degradation in plant. Due to the late stage of seed maturation, the dried seed has completed the transcription of most of the seed genome. Therefore, it is essential to emphasizing research on seed longevity process regulated by post-transcriptional regulation mechanism during seed storage and germination. To this end, the current project intends to use multidisciplinary approaches to study the function of Arabidopsis ATL5 in regulating seed longevity; to analyze the substrate proteins of ATL5, to analyze the regulatory effect of ATL5 on the stability of substrate proteins, and to clarify new post-translational mechanisms of ATL5 in regulating seed longevity. This project will theoretically enrich the mechanism in regulating seed longevity, and practically provide new key resources for molecular design breeding to improve seed storability.