针对H2AK119ub1特异性的DNMT3A与核酶体相互作用的结构基础
Xinyi Chen1, Yiran Guo2,3, Ting Zhao4
1Department of Biochemistry, University of California, Riverside, CA, 92521, USA.
Nature communications
|July 23, 2024
概括
DNA甲基转移酶 DNMT3A1 特别结合于 H2AK119ub1 修饰核体. 这种结构性洞察力揭示了DNA甲基化建立的分子基础及其与病变发生的联系.
科学领域:
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 结构生物学 结构生物学
- 分子生物学分子生物学
背景情况:
- DNA甲基转移酶DNMT3A异型1 (DNMT3A1) 对于建立DNA甲基化模式至关重要.
- DNMT3A1 特别识别了 H2AK119ub1 修饰核体,但这种相互作用的分子基础是未知的.
- 由于调节错误而导致的异常DNA甲基化可能导致致病.
研究的目的:
- 阐明DNMT3A1-核酶相互作用的分子基础.
- 确定DNMT3A1对核体的H2AK119ub1依赖招募的结构机制.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于确定DNMT3A1 UDR片段的结构,该片段与H2AK119ub1修饰核体复合.
- 生物化学分析以调查功能影响和竞争性约束.
主要成果:
- 冷-EM结构显示DNMT3A1 UDR在核体表面广泛结合,包括H2AK119ub1,H2A-H2B酸性补丁和DNA.
- DNMT3A1与H2AK119ub1的相互作用影响了DNMT3A1的细胞功能.
- DNMT3A1和JARID2之间的核细胞结合竞争表明表观遗传路径之间的相互作用.
结论:
- 据报道,H2AK119ub1依赖的DNMT3A1核细胞组关联的分子基础.
- 这种相互作用对DNMT3A1介导的DNA甲基化在发育过程中至关重要.
- 这些发现突出了DNA甲基化与其他表观遗传途径 (如Polycomb抑制) 之间的相互作用.
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