在异染色质调节错误期间绘制表观遗传适应的动态图
bioRxiv : the preprint server for biology
|July 28, 2023
概括
细胞可以通过重新分配质子修饰,如H3K9甲基化,以表观遗传方式适应压力. 这种表观遗传适应是缓慢的,但为未来的环境挑战建立了一个可调节的记忆.
科学领域:
- 表观遗传学和分子生物学
- 细胞适应机制 细胞适应机制
- 基因组学和染色质动力学
背景情况:
- 细胞通过遗传突变进行了经典的适应,但没有DNA变化的表观遗传机制使得适应变化更难理解.
- 建议对适应性表型进行重新分配的质子修饰,特别是H3K9甲基化 (H3K9me).
- H3K9me通常保持基因组完整性,但可以用于适应.
研究的目的:
- 为了研究由H3K9me再分配驱动的表观遗传适应的动态.
- 揭示适应性H3K9me建立的时间尺度和机制.
- 为了确定是否表观遗传状态在消除压力后是可遗传的.
主要方法:
- 开发了一种精确的基因工程方法,以触发H3K9me在裂变酵母中按需重新分配.
- 利用长期连续培养来追踪基因组规模的RNA和染色质变化.
- 在应激暴露之前,期间和之后监测H3K9me动态.
主要成果:
- 适应性H3K9me重新分配发生在相对于应激的缓慢时间尺度上.
- 捕获了动态的H3K9me再分配事件,导致了适应性解决方案的趋同.
- 细胞在消除压力时建立了新的转录和染色质状态,而不是恢复到原始状态.
结论:
- 通过H3K9me再分配进行表观遗传适应是一个缓慢但可遗传的过程.
- 这种机制使细胞能够寻找和编码适应性解决方案.
- 这些发现对理解耐药性和细胞对感染的反应有意义.
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