胆固醇减弱了含有CARC的两性的孔形成能力
Ilya P Oleynikov1, Alexander M Firsov1, Natalia V Azarkina1
1A. N. Belozersky Institute of Physico-Chemical Biology, M. V. Lomonosov Moscow State University, Leninskie Gory 1, Bld. 40, Moscow 119992, Russia.
International journal of molecular sciences
|January 25, 2025
概括
人工P4,A1和A4破坏细胞膜. 含有胆固醇识别序列的A4和P4形成毛孔并影响膜潜力,而A1需要更高度,胆固醇不会阻碍毛孔形成.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 膜生物物理学 膜生物物理学
背景情况:
- 人工酸P4,A1和A4模仿流感M1蛋白质碎片.
- P4和A4具有胆固醇识别序列 (CARC),与A1.1不同.
- 以前的研究表明P4和A4的细胞毒性作用,表明膜破坏.
研究的目的:
- 为了调查质细胞毒性破坏膜假设.
- 分析P4,A1和A4在阿索莱克膜上的解效应.
- 确定胆固醇在酸诱导的膜变化中的作用.
主要方法:
- 研究了A4对脂质体中的膜电位 (Δψ) 的影响,使用瓦利诺米辛-K+扩散和细胞染色体c氧化酶 (CcO).
- 在酸P4,A1和A4的存在下,研究了从脂质体中释放的素.
- 研究了胆固醇对诱导脱和孔隙形成的影响.
主要成果:
- 在亚微分子度下,A4迅速消散了膜电位 (Δψ).
- 脱离含有CcO的蛋白质体需要更高的A4度,这表明酶相互作用.
- 胆固醇的存在削弱了A4的解效应.
- 亚微粒度A4和P4诱导了素的释放,表明孔隙形成,这是由胆固醇减缓的.
- 微分子A1导致胆固醇独立的孔隙形成.
结论:
- 酸P4,A4和A1 (在较高度下) 在阿索莱克膜中形成孔隙.
- 在A4和P4中的CARC序列与胆固醇相互作用,阻碍毛孔形成.
- A4的快速解效应很可能是由于质子导电性增加,而不是孔隙形成.
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