香蕉果实成熟软化过程中淀粉降解的转录调控机制解析

香蕉属于跃变型果实，果实采收后极易成熟软化。未成熟的香蕉果肉主要成分是淀粉，其含量在果实成熟软化过程中急剧下降。淀粉降解是由多种酶共同参与完成的，但目前对于淀粉降解酶在淀粉降解中的作用及其协同调控淀粉降解机制研究较少。转录因子及其蛋白质修饰参与淀粉降解，但转录因子是否可以直接调控果实淀粉降解，从而参与果实成熟软化，其具体的转录调控网络又是什么等关键问题，目前并不清楚。.为此，本项目以两种饱满度不同的香蕉果实为材料，获得参与淀粉降解的主要酶基因家族成员及调控这些成员的转录因子，筛选、鉴定与转录因子修饰有关的互作蛋白，并进一步分析转录因子发生修饰后对其调控淀粉降解关键酶基因的影响。研究结果可以明确参与香蕉果肉淀粉降解相关的转录因子，揭示这些成熟相关转录因子及其蛋白质修饰与果实淀粉降解的关系，对于深入阐明果实成熟调控机制，拓展果实成熟调控网络具有重要的理论意义。

Banana, being a typical climacteric fruit, is highly prone to ripening and softening after harvest. Starch is the primary component in pulp of unripe banana and its content declines dramatically during softening. Starch degradation is a complicated process regulated by several enzymes, but until recently, little information is available about the roles of enzymes involved in starch degradation as well as the mechanism underlying transcriptional regulation of this process. Although transcription factors (TFs) along with their post-translational modifications are known to mediate starch degradation process, some critical issues like whether TFs regulating the starch degradation resulting in ripening and softening of fruit and the corresponding transcriptional regulatory networks are still largely unclear. . In this project, fruit at two different maturity stages were used as experimental materials, members of gene families encoding enzymes involved in starch degradation and their upstream TFs were identified, and then the interacting proteins with these TFs associated with protein modifications are screened and characterized, Moreover, the effect of TFs with post-translational modifications on the regulation of targets involved in starch degradation is also investigated. The results of our project will provide novel information about TFs and their corresponding transcriptional regulatory networks involved in starch degradation, expand our understanding of the relationship between ripening-related TFs along with their post-translational modifications and starch degradation in fruit, and provide a theoretical basis for further elucidating and advancing the regulatory mechanism underlying fruit ripening.