对于酵母酵母的饥饿诱导的分化,需要独立于的翻译
Wendy V Gilbert1, Kaihong Zhou, Tamira K Butler
1Department of Molecular and Cell Biology, Department of Chemistry, and Howard Hughes Medical Institute, University of California, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|September 1, 2007
概括
细胞内部核糖体进入点 (IRES) 能够在压力期间进行蛋白质合成. 这项研究揭示了酵母侵入性生长中IRES功能的一种新机制,证明了它的生理重要性.
科学领域:
- 分子生物学分子生物学
- 酵母遗传学 酵母遗传学
- 基因规则 基因规则
背景情况:
- 细胞内部核糖体进入点 (IRES) 是未被翻译的mRNA区域,在环境压力期间被建议启动独立于cap的翻译.
- 细胞IRES的生理作用和分子机制在很大程度上仍未被描述.
研究的目的:
- 研究酵母细胞IRES的功能和机制.
- 确定IRES介导的翻译在酵母侵入性生长中的作用.
主要方法:
- 对涉及侵袭性生长的七个酵母基因的分析.
- 在这些基因中识别和描述IRES元素.
- 调查翻译启动因子eIF4G的要求.
- 评估 5'UTR A 丰富元素和多A 结合蛋白 (Pab1) 招募的作用.
- 对5'UTR的突变分析以评估IRES活动和侵入性生长.
主要成果:
- 对于侵入性生长至关重要的七个酵母基因具有强大的IRES.
- 这些IRES取决于eIF4G的启动因子,以实现无上限翻译.
- 5'UTR中的一个非结构化,A丰富的元素招募了Pab1,调解了内部启动.
- 这种机制不同于RNA结构依赖的病毒IRESs.
- 破坏IRES活动的5'UTR突变会损害侵入性生长.
结论:
- 细胞IRES在酵母侵入性生长中具有证明的生理功能.
- 在IRES中介的上限独立翻译对于应激适应至关重要.
- 确定的机制涉及Pab1通过A丰富元素的招聘,与病毒IRES机制不同.
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