H/ACA snRNP依赖的核糖体生物发生调节了多重氨酸蛋白的翻译
Shane M Breznak1, Yingshi Peng2, Limin Deng1,3
1Department of Biological Sciences, RNA Institute, University at Albany, 1400 Washington Avenue, LSRB 2033D, Albany, NY 12222, USA.
Science advances
|June 21, 2023
概括
干细胞的分化依赖于核糖体生物发生和翻译. 这项研究揭示了H/ACA小核核糖核蛋白 (snRNP) 复合体选择性地转化CAG重复含有信使RNA,这对卵细胞特异性至关重要.
科学领域:
- 发展生物学 发展生物学
- 分子和细胞生物学分子和细胞生物学
- 遗传学 是一个遗传学.
背景情况:
- 干细胞,包括多索菲拉生殖系干细胞 (GSCs),在终端分化过程中增强核糖体生物发生和翻译.
- 小核核核糖蛋白 (snRNP) 的H/ACA复合体对于核糖体RNA (rRNA) 和核糖体生产的伪化至关重要.
研究的目的:
- 研究H/ACA snRNP复合体在GSC分化和卵细胞特异化中的作用.
- 确定核糖体水平如何影响分化过程中特定信使RNA的翻译.
主要方法:
- 在GSC中,H/ACA snRNP复合物的耗尽.
- 对信使RNA翻译的分析,专注于CAG三核酸重复丰富转录.
- 操纵拉巴胺素 (TOR) 活动的标,以调节核糖体水平.
主要成果:
- H/ACA snRNP复合体对于卵细胞的特异化至关重要.
- 减少的核糖体水平影响了CAG重复含有信使RNA的翻译,包括分化因子.
- 观察到核糖体在 oogenesis 期间的转录中在 CAG 重复时被丰富.
- 升高的TOR活性挽救了H/ACA snRNP复合物-贫乏生殖系中的差异化缺陷.
- 拉帕米辛治疗降低了含有多重谷氨的蛋白质水平.
结论:
- 核糖体生物发生和水平控制干细胞分化.
- 核糖体对CAG重复含有的转录的选择性翻译是关键机制.
- H/ACA snRNP 复合体在 oogenesis 过程中调节翻译起着至关重要的作用.
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