在S1中的疏水性残留物调节电压感应酸酶中的酶功能和电压感应
Vamseedhar Rayaprolu1, Heini M Miettinen1, William D Baker1
1Department of Cell Biology and Neuroscience, Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA.
The Journal of general physiology
|May 21, 2024
概括
电压感应酸酶 (VSP) 的S1螺旋中的突变改变了酶活性和电压感应. S1螺旋对VSP功能至关重要,调整着对电信号的反应变化的结构.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 生物物理学的生物物理.
背景情况:
- 电压感应域 (VSD) 将电信号转化为细胞反应.
- 在大多数蛋白质中,VSD螺旋体S1-S3是结构性的,但在电压感应酶 (VSP) 和质子通道中存在例外.
- 在VSP功能中S1螺旋的特定作用仍未完全阐明.
研究的目的:
- 为了研究S1螺旋对VSP功能的贡献.
- 了解S1螺旋中的突变如何影响VSP活动,动力学和电压依赖.
- 探索S1螺旋在VSD形状变化和VSP二元化中的作用.
主要方法:
- 在VSP的S1螺旋中,四种疏水性氨基酸的局部定向突变发生,转化为氨酸.
- 评估VSP活动的电压依赖性和酶动力学.
- 分析VDS运动的电压依赖性.
- 在基因编码的电压指示器中引入突变.
主要成果:
- 在S1螺旋中的突变将电压依赖转移到更高的电压,改变了基板反应和脱化动力学.
- VSD运动显示电压依赖转移到较低的电压,揭示了第二个电压依赖的运动.
- VSP二分化被保留,这表明内部或间子单元相互作用调解S1螺旋效应.
- 电压指示器的突变改变了光学读数,影响了动力学和电压依赖性.
结论:
- S1螺旋对于调整VSP对膜电位的形态反应至关重要.
- S1螺旋突变显著影响VSP功能和电压感应域动态.
- 这些发现为VSP和相关的电压传感蛋白的调节机制提供了洞察力.
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