表观遗传记忆是由一个效应器的招募特异性在 Heterochromatin 蛋白 1 1 的切换
bioRxiv : the preprint server for biology
|December 11, 2023
概括
异染色蛋白1 (HP1) 同源Swi6氨基酸序列的轻微变化深刻地改变了表观遗传. 这表明一种冗余的机制在染色体调节中演变新的效应特异性.
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.
- 染色体生物学 染色体生物学
背景情况:
- 异染色素蛋白1 (HP1) 蛋白质对于保持转录性沉默的异染色素至关重要.
- HP1蛋白质二元化以招募其他染色质相关因子,在表观遗传中发挥关键作用.
- 对于HP1蛋白的功能专业化所需的变异程度尚不清楚.
研究的目的:
- 调查S. pombe HP1同类物Swi6中氨基酸序列变异如何影响表观遗传.
- 为了确定Swi6中的特定区域,在突变后,导致染色质维护特性发生变化.
主要方法:
- 进行了S. pombe Swi6蛋白的向性突变发生屏幕.
- 在HP1二元化接口附近的辅助表面引入了替换.
- 在体内分析了Swi6变体以检测染色质占用率的变化和蛋白质相互作用.
主要成果:
- 在Swi6中单个氨基酸位置的替代导致了表观遗传遗传的持续增加或损失.
- 这些突变增加了Swi6染色体占用率,并改变了与其他蛋白质的相互作用.
- 修改后的Swi6变种重新编程了H3K9me的维护,这是一个关键的表观遗传标记.
结论:
- 在Swi6中相对较小的氨基酸变化可以导致表观遗传的显著改变.
- 这突出了染色体修饰剂中效应因子特异性的演变的潜在冗余机制.
- 该研究提供了对HP1蛋白的功能专业化和快速演变的分子基础的见解.
相关概念视频
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