EMC纠正了多通道膜蛋白的拓
Haoxi Wu1, Luka Smalinskaitė1, Ramanujan S Hegde2
1MRC Laboratory of Molecular Biology, Cambridge, UK.
Nature structural & molecular biology
|November 13, 2023
概括
哺乳动物的多通路蛋白在碳结末附近,由内质网膜膜蛋白质复合体 (EMC) 在翻译后插入. 这种序列机制确保了适当的蛋白质拓和生物发生.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 蛋白质生物化学 蛋白质生物化学
背景情况:
- 大多数真核生物多通道膜蛋白以共同翻译的方式插入到内质网膜膜.
- 跨膜域 (TMDs) 通常在它们从核糖体中出现时被插入.
研究的目的:
- 在哺乳动物的多通道蛋白中研究卡基终端TMD的插入机制.
- 确定内细胞网膜蛋白复合体 (EMC) 在蛋白质生物发生过程中的作用.
主要方法:
- 特定站点的交叉链接来绘制蛋白质相互作用的地图.
- 对TMD插入和蛋白质拓学的分析.
主要成果:
- 炭基末端TMDs是由EMC在翻译后插入的.
- 通过EMC介导的插入在很大程度上独立于TMD的水性.
- 插入是短的,未充电的C尾和前面未组装的TMD捆的偏好.
结论:
- 多通路蛋白可以在共同翻译上被不完全插入,因此需要在翻译后插入EMC以获得正确的拓和生物发生.
- 这种序列机制可能适用于大约250个多通道蛋白,包括对神经传递至关重要的离子通道子单元.
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