通过Bre1进行的素H2B单双化机制
Fan Zhao1, Chad W Hicks1, Cynthia Wolberger2
1Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Nature structural & molecular biology
|October 23, 2023
概括
基斯H2B的无处不在性调节了关键的细胞过程. Bre1 E3 酶结构显示了它如何结合核细胞和DNA,指导无胺转移,并表明了基因素 E3 酶特异性的一般机制.
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.
- 生物化学 生物化学
背景情况:
- 基斯修饰,如基斯H2B在K120/123的单双化,是基本细胞过程的关键调节者.
- 这些过程包括转录,DNA复制和DNA损伤反应.
- 了解催化这些修饰的酶是解读基因调节和细胞维护的关键.
研究的目的:
- 为了阐明由RING E3结合酶Bre1.1进行的希斯H2B泛化的结构基础.
- 了解Bre1如何与核细胞和DNA相互作用以促进其酶活性.
- 提出一个关于E3结合酶如何实现基因素特异性的一般机制.
主要方法:
- 用X射线晶体学来确定与核细胞组合的Bre1 E3结合酶的结构.
- 生物化学试验用于研究Bre1,核细胞和E2酶Rad6.6之间的相互作用.
- 与其他基因素E3结合酶进行结构比较分析.
主要成果:
- 双重型Bre1 E3酶通过其酸性补丁与核体结合,将E2酶Rad6定位为ubiquitin转移到基因素H2B.
- 一个RING域的Bre1与核体酸性补丁相互作用,而另一个接触DNA.
- 结构洞察力揭示了Bre1的非E2结合的RING域如何可能有助于组蛋白特异性.
结论:
- 与核体结合的Bre1的结构提供了H2B无处不在的分子机制.
- Bre1利用与核细胞和DNA的独特相互作用来实现基质识别和ubiquitin-conjugating酶的定位.
- 这些发现表明,在基因素修饰途径中,E3酶特异性的保存机制存在.
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