在dNTP选择子域中,SNP相关的氨基酸残留替代物降低了聚β聚合酶活性
Olga A Kladova1, Timofey E Tyugashev1, Aleksandr A Miroshnikov2
1Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia.
Biomolecules
|May 24, 2024
概括
在DNA聚合酶β (Polβ) 基因中的单核酸多态性可以改变其功能. 变种G274R,G290C和R333W显示活动减少,可能增加未修复的DNA损伤.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 生物化学 生物化学
背景情况:
- DNA聚合酶β (Polβ) 对于基因组稳定性和基因切除修复 (BER) 是至关重要的.
- 在POLB基因中的单核酸多态 (SNPs) 可以导致Polβ酶性质的改变,并与癌症有关.
- 特定的氨基酸位置 (Gly-274,Gly-290,Arg-333) 与Polβ功能有关,并在瘤中观察到.
研究的目的:
- 为了研究自然发生的多态变体G274R,G290C和R333W的DNA聚合酶β的功能影响.
- 阐明这些特定的氨基酸替代如何影响Polβ的酶活性,DNA结合和聚合效率.
主要方法:
- 进行了动态分析,以量化Polβ变体的酶活性.
- 用分子动力学模拟来检查由氨基酸替代引起的结构和动态变化.
- 进行了空隙填充,原料延长和脱氧核酸三酸结合的测试.
主要成果:
- 这三种多态变体 (G274R,G290C,R333W) 都表现出降低的聚合酶活性.
- 替代的G274R和R333W显著削弱了空隙填充和原料延伸能力.
- 这些变异表明脱氧核酸三酸盐结合亲和力降低,聚合常数较低,与局部蛋白质结构的改变有关.
结论:
- 研究的Polβ变体 (G274R,G290C,R333W) 具有减少的酶功能.
- 这些功能性缺陷表明,在未经修复的DNA损伤的积累中可能发挥作用.
- 这些发现强调了特定的Polβ残留物在维护基因组完整性方面的重要性及其对疾病的影响.
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