通过RAD4/XPC进行损伤识别和DNA结合的最小能量途径
Aadarsh Raghunathan1, Marimuthu Krishnan1
1Center for Computational Natural Sciences and Bioinformatics (CCNSB), International Institute of Information Technology, Gachibowli, Hyderabad, Telangana 500032, India.
Journal of chemical information and modeling
|September 25, 2025
概括
XPC/RAD4蛋白通过识别紫外线损伤的DNA来启动DNA修复. 分子动力学揭示了一种限制速度的DNA扭曲和基础翻转机制,这对于损伤修复至关重要.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 遗传学 遗传学 是一个
背景情况:
- 紫外线辐射会导致DNA损伤,形成pyrimidine-pyrimidone (6-4) 光产物 (6-4PP).
- XPC/RAD4蛋白质复合体对于检测6-4PP和启动核酸切除修复至关重要.
- 了解XPC/RAD4介导的病变识别和修复的精确机制对于基因组完整性至关重要.
研究的目的:
- 阐明XPC/RAD4启动维修紫外线诱导的DNA损伤的分子机制.
- 将XPC/RAD4与受损DNA结合所涉及的能量格局和形状变化映射出来.
主要方法:
- 分子动力学 (MD) 模拟
- 雨采样是统一的采样方式.
- 推拉弹性带 (NEB) 方法来确定最小能量路径 (MEP).
主要成果:
- 最初的DNA审讯涉及部分解和开放,部分损伤挤出.
- 一个限制速度的步骤,以5'基点翻转为特征,被确定为瓶.
- 顺序基点翻转 (损伤,5'基点,3'基点) 和β-hairpin插入稳定了最终的XPC/RAD4-DNA复合体.
结论:
- 这项研究揭示了控制XPC/RAD4DNA修复启动的关键构造中间体和能量.
- 对基翻转机制的洞察力为核酸切除修复提供了更深入的理解.
- 这项工作促进了对与皮肤疾病和癌症相关的DNA损伤反应途径的了解.
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