在它们的膜组装后,Sec18 (NSF) 和Sec17 (SNAP) 促进了膜融合
Hongki Song1, Karina Lopes1, Amy Orr1
1Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755.
Molecular biology of the cell
|October 30, 2024
概括
Sec17和Sec18蛋白驱动膜融合,Sec18和Sec17的N环异极性对于最初的膜结合和随后的融合至关重要. 这个机制调节核聚变能力,独立于SNARE复杂级别.
科学领域:
- 细胞生物学 细胞生物学
- 膜贩运活动 膜贩运
- 蛋白质与蛋白质的相互作用
背景情况:
- 膜融合对于细胞过程至关重要.
- SNARE蛋白质调解了膜融合,能量来自拉链.
- Sec17和Sec18 (分别是酵母Sec17p和Sec18p的同类) 是关键的调节剂.
研究的目的:
- 为了研究Sec18和Sec17 N-域无极环在膜融合中的作用.
- 要确定这些因素是否需要用于膜协会或融合后协会.
主要方法:
- 构建了Sec17 (TM-Sec17) 的一个跨膜定变体.
- 评估了Sec17,Sec18和TM-Sec17存在或不存在的膜融合.
- 量化跨SNARE复合体水平和核聚变能力.
主要成果:
- 对于最初的膜准,Sec18和Sec17无极环是必不可少的.
- 即使不需要膜准,TM-Sec17无极循环也可以增强Sec17/18驱动的融合.
- 聚变能力,而不是跨SNARE复杂水平,是由Sec17,Sec18和Sec17 N-loop规范的.
结论:
- Sec18和Sec17无极循环连续作用:首先用于膜准,然后驱动快速聚变.
- 该Sec17/18复合体调节了对接膜的融合能力,独立于SNARE复合体形成水平.
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