用人类核体重置酵母表观基因组
1Institute for Systems Genetics, Department of Biochemistry and Molecular Pharmacology, NYU Langone Health, New York, NY 10016, USA.
Cell
|December 5, 2017
概括
研究人员用人体基因组替代了"人性化"酵母. 这揭示了基因调节和染色质重塑的洞察力,为研究基因组变异提供了一个新的平台.
科学领域:
- 分子生物学
- 遗传学
- 细胞生物学
背景情况:
- 基因组对于人类和酵母的基因调节至关重要,尽管有十亿年的进化差异.
- 保存的基质子功能突出显示了染色质结构在基本细胞过程中的重要性.
研究的目的:
- 在酵母中研究人类核细胞的功能兼容性.
- 探索酵母在利用人体染色体时使用的适应机制.
- 建立一个新的酵母模型来研究人类的基因组变异和表观遗传学.
主要方法:
- 酵母菌株被设计为表达人类核心核体,取代内源性酵母组织蛋白.
- 分析了细胞分裂基因的适应性和抑制性突变.
- 为了恢复强壮的生长,进行了基因组残留转化.
- 核素定位,DNA占用率,RNA含量和染色体重塑动态进行了评估.
主要成果:
- 人类核细胞最初只能与基因组变异H3.1功能,需要显著的细胞适应.
- 酵母通过抑制突变或无体积变异而适应,以及特定的基因组残留变化恢复了生长.
- 人类核体采用了类似酵母的定位和重复的长度,受酵母DNA和染色体重塑剂的影响.
- 人类核细胞具有更高的DNA占用率,减少了全球RNA含量,并且染色质重塑受损,减缓了适应.
结论:
- 人性化的酵母模型提供了一个独特的平台来剖析染色质功能和基因组变异的作用.
- 这项研究揭示了核体结构和动态的差异如何影响基因调节和细胞适应.
- 这项研究为了解色素与多种细胞过程之间的联系开辟了新的途径.
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