灵活性和分布式合成调节人类DNA聚合酶α-酶中的RNA原始化和移交
John J Cordoba1,2, Elwood A Mullins2,3, Lauren E Salay1,2,4
1Chemical and Physical Biology Program, Vanderbilt University, Nashville, Tennessee, USA.
bioRxiv : the preprint server for biology
|August 14, 2023
概括
细胞DNA复制需要通过聚合酶α-原酶 (pol-prim) 来合成RNA/DNA原料. 它的 PRIM2C 域名.
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:
- 细胞DNA复制始于由聚合酶α-原酶 (pol-prim) 进行的RNA/DNA原始合成.
- 聚原酶包括原酶 (PRIM1/PRIM2C) 和聚合酶α (POLA1cat) 的子单元.
- PRIM2C调节RNA原料合成,然后转移到POLA1cat进行DNA扩展.
研究的目的:
- 阐明通过pol-prim.调节RNA原料合成的机制.
- 为了研究结构动力学和基质亲和力调节多元原始函数.
- 了解PRIM2C,PRIM1和POLA1cat在原料合成和交付中的相互作用.
主要方法:
- 微角X射线散射 (SAXS) 和电子显微镜 (EM) 用于研究聚原体结构.
- 交叉连接与EM相结合,可视化基质结合酶的方向.
- 微尺度热泳 (MST) 用于量化基质结合亲缘关系.
主要成果:
- 聚烯表现出显著的结构变异性,合成能力较低的构造物种群.
- PRIM1催化域对模板和RNA原始模板的亲和力很低.
- PRIM2C显示出高度的亲和力和灵活的链接,促进了原料合成和交付.
结论:
- 通过PRIM2C的灵活,高亲和度的相互作用和PRIM1的低亲和度来控制RNA原始合成.
- 域间的灵活性和差异化的基质亲和力决定了高效的原料合成和转移到聚合酶α.
- 这种机制确保了真核细胞DNA复制的准确启动.
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