一种化的II组内体样反转录酶在宿主细胞DNA修复中发挥作用的演化结构基础
Seung Kuk Park1, Mo Guo1, Jennifer L Stamos1
1Departments of Molecular Biosciences and Oncology, University of Texas at Austin, Austin, TX 78712, USA.
bioRxiv : the preprint server for biology
|January 27, 2025
概括
细菌逆转录酶 (G2L4 RT) 通过微同质介导端结合 (MMEJ) 稳定双链断裂修复 (DSBR) 来帮助DNA修复. 结构洞察力揭示了在DNA修复途径中优化其细胞功能的适应.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
背景情况:
- 之前已经证明,一种化的II组细菌内部类似逆转录酶 (G2L4 RT) 能够通过微同质介导端结合 (MMEJ) 在双链断裂修复 (DSBR) 中发挥作用.
- 移动II组内部编码的RT具有基本的DSBR活动,利用非LTR-retroelement的RT共同的结构特征.
研究的目的:
- 确定G2L4 RT在DSBR中的功能结构基础.
- 阐明新的结构适应,优化G2L4 RT在DSBR中的细胞作用.
主要方法:
- 使用X射线结晶学来确定G2L4 RT.的阿波酶结构.
- 确定了G2L4 RT的快回DNA合成结构,以了解基质相互作用.
主要成果:
- 确定了一个独特的RT3a结构,稳定了在非活性状态中的阿波酶,直到基质结合.
- 发现更长的N端延伸/RT0循环和修改后的活性部位有利于线程化.
- 一个保存的二聚体接口促进了G2L4 RT同聚体定位到DSBR站点,为MMEJ定位单聚体.
结论:
- G2L4 RT具有独特的结构适应性,优化其在DSBR中的细胞功能.
- 这些发现揭示了非LTR-retroelement RT对于专门的细胞作用的演变.
- 这项研究表明,优化RTs用于基因组工程应用的潜力.
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