具有异常DNA聚合酶活性的POLQ变体可以防止紫外线诱导的细胞死亡
bioRxiv : the preprint server for biology
|December 8, 2025
概括
变异型DNA聚合酶Q (POLQ) 在修复循环butan胺二次体 (CPD) 中显示效率降低,但可以保护细胞免受紫外线辐射诱导的死亡,这表明它在癌症中起着双重作用.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 癌症研究 癌症研究
背景情况:
- 基因组聚合酶对基因组稳定性至关重要,防止基因突变导致未经修复的DNA损伤.
- 包括DNA聚合酶Q (POLQ) 在内的DNA修复途径的变体与各种癌症有关.
- 最近对黑色素瘤中的POLQ变体的鉴定突出了它们在癌症进展中的潜在作用.
研究的目的:
- 为了研究患者衍生的POLQ变体的DNA修复能力.
- 评估POLQ变体在绕过和延伸DNA超越循环butan胺二元体 (CPD) 的作用.
- 为了确定POLQ变异对紫外线辐射暴露后细胞存活率的影响.
主要方法:
- 生化分析测量DNA聚合酶活性.
- 测试POLQ变种在CPD病变中绕过和扩展DNA的能力.
- 在存在POLQ变异的情况下,在紫外线暴露后评估细胞活力.
主要成果:
- 与野生型 (WT) POLQ相比,来自患者的POLQ变体在绕过和扩展CPD病变的DNA方面表现出较低的效率.
- 在DNA合成过程中,POLQ表现出更喜欢合蛋白的偏好.
- 在三种测试的POLQ变体中,有两种提供了对紫外线诱导的细胞死亡的保护.
结论:
- 波尔克变种已经损害了CPD DNA损伤绕过和延伸能力.
- 波尔克在DNA修复中发挥作用,偏好用于 purin 结合.
- POLQ变种可以提高细胞存活率,可能有助于基因组不稳定性和癌症细胞活力.
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