ER来源的COPII囊泡是自噬隔离膜（IM）和自噬体形成的膜来源之一，但其与自噬相关膜结构互作机制尚不清楚。已有文献报道酵母ER上形成COPII囊泡的区域（ERES）紧邻新月形IM尖端，此处恰为自噬关键跨膜蛋白Atg9在IM上的定位位点。我们前期研究证明衣被蛋白Sec24磷酸化调控COPII囊泡由ER-Golgi运输向自噬通路分流，并促进Sec24-Atg9结合。不能被磷酸化的突变体中，Sec24-Atg9结合和IM形成受阻，但ER-Golgi运输不受影响。故推测：Hrr25通过磷酸化Sec24，调控Sec24-Atg9结合，介导COPII囊泡与IM互作，促进IM形成和延伸。我们将以酵母为模型，综合运用超高分辨率显微成像、电镜、活细胞成像等技术，阐明COPII-IM互作模式、分子基础和对自噬体形成的影响，并探索利用体外重构系统模拟互作过程，从而验证假说并为绘制膜性结构互作网络图谱提供信息。

ER-derived COPII vesicles have been proposed to be membrane source for isolation membrane (IM) and autophagosome formation during nutrient starvation. The mechanism of the interaction between COPII vesicles and autophagic membranes is not clear. It has been reported in the budding yeast Saccharomyces cerevisiae., ER exit site, a specialized domain of ER where COPII vesicles are formed, is associated with the edge of IM where the autophagy related transmembrane protein Atg9 is localized. Our preliminary data showed the phosphorylation of the membrane-distal surface of the COPII coat protein Sec24 by Hrr25 kinase facilitates the interaction of Sec24 with Atg9 to regulate the abundance of autophagosomes during starvation. Phosphorylation of Sec24 is specifically required for macroautophagy, but not ER-Golgi transport. In Sec24 T324A/T325A/T328A mutant which can’t be phosphorylated by Hrr25，Sec24-Atg9 interaction and IM formation are affected while ER-Golgi transport is essentially normal. To test the hypothesis that phosphorylation of Sec24 by Hrr25 facilitates the Sec24-Atg9 binding and COPII-IM interaction, a variety of approaches including super-resolution SIM microscropy、electron microscropy、live cell imaging and autoradiography will be used to explore the interaction between COPII vesicles and isolation membrane and determine the role of Sec24 phosphorylation in this process. In vitro reconstitution will also be used to identify precise molecular mechanisms involved in the COPII-IM interaction. Our studies will facilitate the detailed mechanistic understanding of interaction between COPII vesicles and autophagic membrane structure and provide information for generating membranous structure interactome maps.