重新定义80S单体的翻译状态
Erin E Heyer1, Melissa J Moore1
1Howard Hughes Medical Institute, RNA Therapeutics Institute and Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA.
Cell
|February 13, 2016
概括
在酵母体中,单体,不仅仅是多体,都在积极转化mRNA. 这种核糖体群对于调节特定mRNA的翻译至关重要,包括那些被无意中介衰变 (NMD) 准的.
科学领域:
- 分子生物学
- 遗传学
- 生物化学
背景情况:
- 核糖体以单体和多体的形式存在,多体被广泛研究.
- 单体细胞中翻译的作用和范围仍然存在争议和不太了解.
- 了解单体的功能是了解细胞蛋白质合成的关键.
研究的目的:
- 研究Saccharomyces cerevisiae中的80S单体的转化活性和意义.
- 确定单体池中的启动与延长核糖体的比例.
- 识别与单体占用相关的mRNA特征.
主要方法:
- 使用核糖体分析来分析80S单体的转化状态.
- 在不同的mRNA群体中量化了核糖体占用率.
- 与特定的mRNA特征和调节作用相关的单体丰富.
主要成果:
- 大多数80S单体被发现是积极延长的,而不是启动翻译.
- 大多数mRNA显示了一些单体占用,在无意中介衰变 (NMD) 目标和上游开放读取框架 (uORF) 上进行了丰富.
- 单体在较短的ORF和相对于启动时间的较快延长的ORF中占主导地位,特别是编码低丰度调节蛋白的ORF.
结论:
- 单体在整体转化输出中起着重要的,但往往被低估的作用.
- 单体占用是特定mRNA子集的关键调节机制,包括NMD目标和调节蛋白的mRNA.
- 这些发现强调了单体在通过翻译精确调节基因表达的重要性.
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