降解的26S蛋白质组的结构景观揭示了TXNL1的结构特异性结合
Connor Arkinson1,2,3, Christine L Gee1,2,3, Zeyuan Zhang4
1California Institute for Quantitative Biosciences, University of California at Berkeley, Berkeley, CA, USA.
Nature structural & molecular biology
|November 6, 2025
概括
26S蛋白质组根据其活动状态不同地使用辅因子TXNL1. 时间解析的冷EM揭示了TXNL1如何结合并调节蛋白质降解和由蛋白质酶体展开.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 生物化学 生物化学
背景情况:
- 26S蛋白酶对细胞蛋白质降解,平衡和质量控制至关重要.
- 蛋白质体相互作用的辅因子动态调节蛋白质体功能和基质降解.
研究的目的:
- 为了阐明与人类26S蛋白质组结合的氧化还原活性辅因子TXNL1的高分辨率结构.
- 了解TXNL1结合如何随着蛋白酶体构造和ATPase运动状态而变化.
主要方法:
- 时间分辨率的冷电子显微镜 (cryo-EM) 在和和亚基显微镜TXNL1度.
- 生物物理和生物化学实验.
- 高分辨率的结构确定.
主要成果:
- 鉴定出了不同的TXNL1结合模式,这取决于蛋白质体构造和ATPase活性.
- TXNL1在静止状态的蛋白酶体中表现出低亲和度结合,并在积极降解状态中表现出高亲和度结合,覆盖了Rpn11的催化槽.
- 化EM结构捕获了蛋白酶体展开基质 (mEos3.2) 并揭示了转位期间的ATPase六合体动态.
结论:
- 蛋白质体的不同构造状态协调辅因子结合和基质处理.
- 这些发现提升了通过AAA+电机进行蛋白质转位的模型.
- TXNL1在调节蛋白质酶体介导的蛋白质降解和展开方面发挥着关键作用.
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