植物ESCRT组分AtBRO1调控可溶性液泡蛋白运输参与种子发育的分子机制

液泡在植物生长发育、防御以及其它许多生理过程中发挥重要作用。种子内液泡蛋白如何正常储藏是一个重要科学问题。申请人在前期研究中发现植物内吞体分选转运复合物（ESCRT）新型组分AtBRO1调控膜蛋白分选至液泡，并在近期初步发现AtBOR1可调控液泡分选受体（VSR）的转运，参与可溶性液泡蛋白的运输和种子发育。基于此，本项目将以拟南芥为材料，明确AtBRO1参与种子发育过程中可溶性液泡蛋白转运的功能，探讨AtBRO1影响VSR转运的分子基础，鉴定AtBRO1蛋白复合体组分，并最终阐明AtBRO1蛋白复合体相互协作调控种子内可溶性液泡蛋白转运的分子机制。本项目研究成果将对植物种子内液泡蛋白转运机制，尤其是植物ESCRT在可溶性液泡蛋白、膜蛋白液泡运输过程中交叉调控机制有一个较全面和清晰的认识，将为农林作物种子品质改良提供理论依据。

Vacuole plays vital roles in plant development, defense, and many physiological processes. How the vacuolar protein in the seed properly stored and precisely controlled are important scientific questions. In the previous studies, we have identified a new plant ESCRT component AtBRO1 which is involved in membrane proteins transport into the vacuole. In the preliminary studies, we found that AtBRO1 plays function in the soluble vacuolar proteins transport, including the seed storage proteins and lytic enzymes. Based on these results, we propose to investigate the molecular mechanism of AtBRO1 in the process of soluble vacuolar proteins transport during seed development in Arabidopsis. The main researches include: 1) to confirm the function of AtBRO1 in the soluble vacuolar proteins transport during seed development; 2) to discover the molecular basis of AtBRO1 in regulating the VSR sorting; and 3) to identify the AtBRO1 protein complex and thus reveal their molecular functions in soluble vacuolar proteins transport during seed development. These studies will greatly improve our understanding of the regulatory mechanisms of vacuolar protein transport during seed development. Especially, it will bring new insights about the ESCRT function of cross-talk between soluble vacuolar protein transport and membrane protein sorting in plants. This project will finally provide theoretical supports for improving the quality of crop seeds.