作为自细胞生物发生的支架Atg17综合体的架构
Michael J Ragusa1, Robin E Stanley1, James H Hurley1
1Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892.
Cell
|December 11, 2012
概括
宏自包括在前自体结构 (PAS) 的Atg9囊泡中形成一个光体. 晶体结构揭示了Atg17-Atg29-Atg31复杂二分化如何驱动PAS形成并启动光体组装.
科学领域:
- 细胞生物学 细胞生物学
- 结构生物学是结构生物学.
- 生物化学 生物化学
背景情况:
- 宏观自是一种重要的细胞过程,用于降解和回收细胞质成分.
- 胞形成是宏自的初始步骤,由酵母体的自前结构 (PAS) 介导.
- 该PAS作为一个核化站点用于光体组装,涉及特定的蛋白质,如Atg9.
研究的目的:
- 阐明在PAS早期的法戈核形成的结构基础.
- 了解Atg17-Atg29-Atg31复合体在PAS组织和自启动中的作用.
- 为了研究Atg17含有囊泡被招募和组织到孔中的机制.
主要方法:
- 使用X射线晶体学来确定2:2:2Atg17-Atg29-Atg31复合体的3.05 Å分辨率结构.
- 结构分析的重点是Atg17的新月形状和复合物的二元化接口.
- 该研究还考虑了Atg1及其EAT域在膜结合和曲率传感中的功能作用.
主要成果:
- 晶体结构揭示了Atg17-Atg29-Atg31复合体内一个半月形的Atg17蛋白.
- 确定Atg17-Atg31-Atg29复合体的二元化对于PAS形成和自是必不可少的.
- 发现Atg1的C端EAT域感知了膜曲率,并介导了囊泡结合,促进了孔的形成.
结论:
- Atg17-Atg29-Atg31复合体的二维结构为PAS的Atg9囊泡组织提供了一个结构框架.
- 这种组织对于在宏观自过程中启动孔形成至关重要.
- 这些发现表明一种机制,其中蛋白质复合体二元化和膜曲率感应合作构建初始自细胞体.
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