膜蛋白序列直接翻译后插入的特点
Ilya A Kalinin1, Hadas Peled-Zehavi1, Alon B D Barshap1
1Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel.
Nature communications
|November 25, 2024
概括
许多膜蛋白 (MPs) 使用后翻译途径进行C端螺旋体插入,由特定的C尾序列和YidC插入酶指导. 这确保了适当的蛋白质折叠,并预防疾病.
科学领域:
- 分子生物学分子生物学
- 蛋白质生物化学 蛋白质生物化学
- 细胞机制 细胞机制
背景情况:
- 多延伸膜蛋白 (MP) 需要精确的跨膜螺旋 (TM) 插入才能进行适当的折叠.
- TM插入通常发生在通过Sec translocon的翻译过程中.
- 对于C端TM (cTM) 插入的机制仍然不太了解.
研究的目的:
- 研究MP中C端跨膜螺旋体 (cTM) 的插入机制.
- 为了确定参与cTM插入的细胞机械和蛋白质特征.
- 了解cTM插入缺陷在疾病中的影响.
主要方法:
- 在不同生物体中对MP序列进行比较分析.
- 在大肠杆菌和人类细胞系中进行变异性研究,以评估cTM插入.
- 在cTM插入中涉及的插入酶蛋白的识别.
主要成果:
- 许多MP使用后翻译途径进行cTM插入,绕过Sec的翻译连接.
- 进化优化了C端尾的水友性和长度,以实现高效的cTM插入.
- 在C端尾部的突变破坏了cTM插入,导致蛋白质缺陷,功能丧失和遗传疾病.
- Oxa1家族成员YidC作为E. coli*中cTMs的插酶.
- C尾突变损害了cTMs和YidC之间的相互作用.
结论:
- 膜蛋白序列是精细调整的,以与细胞生物发生机制相互作用,以便适当折叠.
- 由YidC介导的翻译后插入途径对于特定的膜蛋白来说至关重要.
- 这条通路的缺陷有助于人类遗传疾病.
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