谱系特异性氨基酸定义了Rad51和Dmc1重组酶的原质子-原质子接口的功能属性
Mike Petassi1, Yeonoh Shin1, Aidan M Jessop1
1Department of Biochemistry & Molecular Biophysics, Columbia University Irving Medical Center, New York, New York, USA.
The Journal of biological chemistry
|December 10, 2025
概括
DNA重组Rad51和Dmc1的演化方式不同. Rad51限制了芳香残留物,而Dmc1具有更广泛的功能格局,突出了它们独特的进化路径.
科学领域:
- 分子生物学分子生物学
- 进化生物学 进化生物学
- 结构生物学 结构生物学
背景情况:
- 细胞有两个主要的DNA重组:Rad51 (分裂和半分裂) 和Dmc1 (仅发生半分裂).
- 这些蛋白质被认为起源于一个单一的祖先基因复制事件.
- 了解它们的进化关系是解读它们独特功能的关键.
研究的目的:
- 为了研究Rad51和Dmc1DNA重组之间的进化关系.
- 分析Rad51和Dmc1.1.之间的保存芳香残留物中的结构和功能差异.
- 探索这两个关键重组的功能约束和进化轨迹.
主要方法:
- 高分辨率冷电子显微镜 (cryo-EM) 用于确定与单链DNA (ssDNA) 结合的Saccharomyces cerevisiae Rad51和Dmc1丝的结构.
- 生物信息分析以确定保存的残留物.
- 自然序列变异的遗传分析和深度突变分析,以探测功能耐受性.
主要成果:
- 化EM结构揭示了一对堆叠的界面芳香氨基酸残留物,这些残留物在Rad51中保存,但在Dmc1.1中不存在.
- 功能分析显示,Rad51纤维中的这些芳香残留物具有高度受约束的序列空间.
- 相比之下,Dmc1丝在同等位置呈现出广泛的功能景观.
结论:
- Rad51和Dmc1的独特进化路径是由它们的界面芳香残留的差异突出显示的.
- 这些结构和功能差异可能有助于Rad51和Dmc1在DNA修复和重组中的独特作用.
- 这项研究提供了对重组酶进化和功能专业化的分子基础的见解.
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