特普辛绑定LC3B以促进ATG9A的贩运和交付
Natalie S Wallace1,2, John E Gadbery1,2, Cameron I Cohen1,2
1Department of Biological Sciences, Vanderbilt University, Nashville, TN 37232.
Molecular biology of the cell
|February 21, 2024
概括
素蛋白与LC3B结合,对于从高尔基河运输ATG9A至关重要. 素的损失破坏了自细胞结构和ATG9A向细胞外围的传递.
科学领域:
- 细胞生物学 细胞生物学
- 分子和细胞生物学分子和细胞生物学.
- 蛋白质相互作用 蛋白质相互作用
背景情况:
- 素是适应蛋白4 (AP-4) 囊泡中的辅助蛋白.
- AP-4囊泡从跨戈尔吉网络 (TGN) 运输ATG9A,这对于自细胞生物发生是必不可少的.
- 目前尚不清楚特普辛的生物功能.
研究的目的:
- 为了调查tepsin的生物作用.
- 为了确定tepsin与自相关蛋白质的相互作用.
- 阐明特普辛在货物贩运和自细胞生物发生中的作用.
主要方法:
- 在tepsin.co中的LC3-交互区域 (LIR) 图案的in silico识别.
- 生物化学测定 (热量测量) 和结构建模以表征tepsin-LC3B相互作用.
- 在HeLa细胞中进行siRNA敲击,以评估tepsin在ATG9A贩运和自细胞形成中的作用.
- 野生类型和突变型特普辛的重新引入,以确认其功能性作用.
主要成果:
- 素通过其LIR动机直接通过微分子亲和力与LC3B结合.
- 特普辛的枯竭破坏了TGN和其外围分布的ATG9A出口.
- 素的损失会增加自细胞体积和数量,但不会影响自细胞的流量.
- 突变tepsin的LIR动机或N端损害了ATG9A的局部化.
结论:
- 特普辛在TGN的货物出口中发挥着重要作用.
- 素对于含有ATG9A的囊泡的正确输送至关重要.
- 素通过与LC3B的相互作用,有助于自细胞的结构完整性.
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