反应剂和产品的协同合效应促进了Sir2中的脱乙烯化循环
Zhen Bai1, Duy Phuoc Tran1, Akio Kitao1
1School of Life Science and Technology, Institute of Science Tokyo, 2-12-2 Ookayama, Meguro, Tokyo 152-8550, Japan.
Journal of chemical information and modeling
|October 13, 2025
概括
通过辅因子结合循环动态,Sir2脱乙酶活性由p53乙化调节. 乙化p53的结合打开了NAD+的口袋,通过tandemallostery增强了脱乙化.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 翻译后的修改,如Nε-乙化,对于蛋白质功能调节至关重要.
- 赛尔图因 (例如,SIRT1,Sir2) 是依赖NAD+的脱乙酶,影响转录,新陈代谢和应激反应.
- 特别是K382的p53乙化会影响其稳定性和活性,但涉及Sir2的机制尚不清楚.
研究的目的:
- 研究Sir2辅因子结合环 (CBL) 在NAD+结合和p53.3脱乙烯化中的作用.
- 阐明 Sir2 与乙化和非乙化 p53 复合体中的结构动态.
主要方法:
- 传统的分子动力学 (MD) 模拟.
- 平行级联选择MD (PaCS-MD) 模拟.
- 转移分析. 转移分析.
主要成果:
- p53乙化诱导Sir2的CBL的结构变化,调节NAD+结合口袋状态 (开放/关闭).
- 乙化p53结合促进了一个开放的NAD+口袋 (前进异质体),而非乙化p53结合则有利于一个封闭的状态 (反向异质体).
- 乙化K382启动信号通路,汇聚到CBL,突出其在NAD+结合和脱乙化中的作用,通过"并列化"机制.
结论:
- Sir2的CBL对于调节NAD+结合和p53脱乙基化至关重要.
- 受到p53乙化状态影响的CBL的构造动力学,通过连续的全效应驱动加速反应周期.
- 这项研究揭示了一种新的Sirtuin活性调节机制,涉及p53乙化和合化.
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