通过效应体结合和局部电荷对Lon蛋白酶的Allosteric调制
Justyne L Ogdahl1, Peter Chien1
1University of Massachusetts, Amherst, Department of Biochemistry and Molecular Biology Molecular and Cellular Biology Program.
bioRxiv : the preprint server for biology
|September 16, 2024
概括
单链DNA结合通过增强ATP水解和蛋白质降解来激活Lon蛋白酶. 影响DNA结合部位的突变揭示了Lon蛋白酶活性和寡合化的电荷依赖调节.
科学领域:
- 生物化学 生化学
- 分子生物学分子生物学
- 蛋白质组学是指蛋白质组学.
背景情况:
- 与多种细胞活动相关的ATPase (AAA+) 蛋白酶家族对于细胞蛋白质分解和应激反应至关重要.
- 隆蛋白酶是一种AAA+蛋白酶,通过核酸和基质结合而被全质调节.
- 结合DNA对隆蛋白酶活性的特定影响在很大程度上仍未被描述.
研究的目的:
- 通过单链DNA (ssDNA) 结合来研究Lon蛋白酶的调节.
- 为了确定Lon蛋白酶的一般激活策略.
- 阐明静电相互作用在伦蛋白酶调节中的作用.
主要方法:
- 生化分析测量ATP水解速率和蛋白质降解.
- 位点定向的突变发生改变DNA结合残留物.
- 单分子测量以分析Lon蛋白酶寡合化.
主要成果:
- ssDNA结合通过增加ATP水解率和蛋白质基质降解来增强Lon蛋白酶活性.
- 对于ssDNA结合至关重要的基本残留物中的突变以电荷依赖的方式影响Lon活性.
- 在DNA结合部位引入负电荷模仿ssDNA诱导的激活,而电荷中和降低了活性.
- 伦蛋白酶活性的变化与其寡合体状态的变化相关.
结论:
- 伦蛋白酶活性是由静电相互作用调节的,包括通过ssDNA结合介导的相互作用.
- 在DNA结合部位的特定电荷分布可以直接影响Lon蛋白酶功能和寡合化.
- 这项研究揭示了Lon蛋白酶的新型调节机制,突出了DNA结合,电荷和酶活性之间的相互作用.
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