对DNMT3B的全调节和动态组合的结构基础
Jiuwei Lu1, Jian Fang1, Hongtao Zhu2
1Department of Biochemistry, University of California, Riverside, CA92521, USA.
Nucleic acids research
|November 9, 2023
概括
DNA甲基转移酶DNMT3B的寡合化受其域的调节,影响DNA甲基化. 这项研究揭示了对DNMT3B的结构性见解.
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:
- 对DNA甲基转移酶DNMT3B的寡合化对其功能至关重要.
- 在动态组合中,DNMT3B的N端域 (PWWP,ADD) 和C端甲基转移酶 (MTase) 域之间的相互作用尚未完全理解.
研究的目的:
- 阐明DNMT3B寡合化及其调节的结构机制.
- 调查PWWP和ADD域在DNMT3B的自身抑制和性调节中的作用.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于确定 DNMT3B 在各种寡合体状态中的结构.
- 生物化学试验用于研究域相互作用和功能影响.
主要成果:
- ADD域与MTase域相互作用,形成类似于DNMT3A的自身抑制性构造.
- PWWP域和ICF突变参与DNMT3B四聚体形成的全调节.
- 对ADD和PWWP域与基因素修饰的差异性结合 (H3K4me0,H3K36me3) 影响了DNMT3B的功能.
- DNMT3B的寡合化与其基质结合位点的折叠相结合.
结论:
- 结构和生化数据为DNMT3B的全调节提供了机械洞察力.
- 这项研究阐明了DNMT3B的动态组装和调节,通过域相互作用和寡合化.
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