细胞酵母V1-ATPase旋转机制的洞察力是由高分辨率单分子研究揭示的
Seiga Yanagisawa1, Zain A Bukhari1, Karlett J Parra2
1School of Life Sciences, Arizona State University, Tempe, AZ, United States.
Frontiers in molecular biosciences
|April 3, 2024
概括
这项研究揭示了缺少H和C子单元的真空ATP依赖性质子 (V-ATPases) 的独特旋转动力学. 这些发现为V-ATPases的旋转机制及其与F型ATPases的差异提供了新的见解.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 真空ATP依赖性质子 (V-ATPases) 是旋转机器,对于细胞过程至关重要.
- 细胞V-ATPases通过涉及C和H子单元的可逆分解来调节.
- 通过ATP水解,通过V1和Vo复合体驱动质子.
研究的目的:
- 为了研究缺乏H和C子单元 (V1ΔHC) 的Saccharomyces cerevisiae V1-ATPase的高分辨率单分子旋转动力学.
- 为了阐明在ATP水解过程中以前未被描述的旋转状态和停留时间.
- 为了比较V-ATPases与F型ATPases的旋转机制.
主要方法:
- 高分辨率单分子研究跟踪时间和旋转位置.
- 在缺乏H和C子单元 (V1ΔHC) 的Saccharomyces cerevisiae中分析V1-ATPase旋转.
- 研究限制MgATP对旋转动态的影响.
主要成果:
- V1ΔHC旋转表现出120度的电动冲击,具有明显的停留时间.
- 独特的特点包括摇摇欲的旋转,~45°的停留,以及更长的~112°的停留.
- 约112°停留时间和发生率在限制MgATP时增加,表明MgATP结合.
- 建议MgADP释放发生在45°左右.
结论:
- 该研究提供了关于V1ΔHC旋转动态的第一个高分辨率单分子数据.
- 结果为V-ATPases中旋转机制的分子基础提供了新的见解.
- 突出了V型和F型ATPases之间的基质结合和产品释放旋转位置的关键差异.
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