通过mRNA分离的激活剂进行一般的翻译抑制
1Howard Hughes Medical Institute, Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona 85721, USA.
Cell
|September 24, 2005
概括
Dhh1p和Pat1p蛋白抑制翻译并促进处理器官中的mRNA降解. 它们的活动平衡翻译,影响细胞控制.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
背景情况:
- 细胞mRNA的命运涉及翻译终止和组装到信使核糖蛋白 (mRNP) 复合体中.
- 这些mRNP积聚在处理体 (P体) 中,这是mRNA衰变和室内降解机制的关键地点.
- 了解从翻译到mRNA衰变的过渡对于细胞调节至关重要.
研究的目的:
- 为了确定参与mRNA从翻译到P体积累的转换中的蛋白质.
- 阐明脱皮激活剂 Dhh1p 和 Pat1p 在转化控制和 P 体形成中的作用.
- 研究Dhh1p和Pat1p调节mRNA命运的机制.
主要方法:
- 对缺乏或过度表达 Dhh1p 和 Pat1p 的酵母菌株进行基因分析.
- 在体外翻译试验中使用 Dhh1p.
- 在体内实验涉及抑制转化启动的实验.
主要成果:
- Dhh1p和Pat1p的功能是翻译抑制剂和P体形成的促进剂.
- 缺少 Dhh1p 和 Pat1p 的菌株在 mRNA 分割,P 体形成和转化抑制中表现出缺陷.
- 过度表达 Dhh1p 或 Pat1p 会导致翻译抑制,P体形成和生长停止.
- Dhh1p及其人类同类RCK/p54在体外抑制翻译;通过抑制体内翻译启动来绕过这种抑制.
结论:
- Dhh1p和Pat1p介导着一种保存的转化抑制机制,该机制针对mRNA进行切割.
- 这种机制是翻译控制的重要组成部分,并且与积极翻译具有竞争平衡.
- 改变这种平衡是调节基因表达在翻译水平的一个基本方面.
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