人类Bre1复合体与核酶体结合的结构
Shuhei Onishi1, Kotone Uchiyama1, Ko Sato1
1Department of Biochemistry, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
Nature communications
|March 23, 2024
概括
Bre1复杂结构揭示了它是如何向基因组H2B进行单基因化,这是基因调节和DNA修复的关键过程. 这种结构洞察力澄清了由Bre1A/RNF20和Bre1B/RNF40蛋白质对基因素修饰的机制.
科学领域:
- 分子生物学分子生物学
- 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
背景情况:
- 在Lys120的基因组H2B单双化 (H2Bub1) 对于调节转录和DNA修复至关重要.
- 人类的Bre1复合体,包括Bre1A/RNF20和Bre1B/RNF40,催化H2Bub1.1.
- Bre1蛋白质作为瘤抑制剂,但可以在特定情况下促进癌细胞的增殖.
研究的目的:
- 为了阐明 H2B K120 由 Bre1 复合体所产生的无所不在的结构基础.
- 了解控制这种关键的组素修饰的调节机制.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于确定与核体结合的人类Bre1复合物的结构.
- 生物化学和突变分析,以调查蛋白质核细胞相互作用和无处不在活性.
主要成果:
- 冷-EM结构揭示了Bre1A和Bre1B的RING域如何与核细胞的酸性补丁和DNA相互作用.
- 这些相互作用使该复合物能够招募E2酶和乌比奎用于H2BK120的乌比奎化.
- 突变数据表明RING域的双结合方向,Bre1A与酸性补丁的结合对于无处不在是必不可少的.
结论:
- 这项研究提供了对由Bre1复合体介导的H2BK120特异性无处不在的原子层次见解.
- 研究结果表明,核体DNA的灵活性可能在H2B单双化中起着调节作用.
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