细胞转化增强剂元素,招募真核生物启动因子3的细胞转化增强剂元素
Jiří Koubek1, Jaswinder Kaur1, Shivani Bhandarkar1
1Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, USA.
概括
细胞启动因子3 (eIF3) 与特定的mRNA序列结合,影响蛋白质的产生. 这一发现揭示了调节基因表达的新机制,特别是在压力条件下.
科学领域:
- 分子生物学分子生物学
- 基因表达规范 基因表达规范
- 蛋白质合成 蛋白质合成
背景情况:
- 翻译启动是控制真核生物基因表达的关键,高度调节的步骤.
- 细胞启动因子3 (eIF3) 在核糖体招募中发挥关键作用,用于正规和替代翻译途径.
研究的目的:
- 研究eIF3与5'-未翻译区域 (5' UTRs) 的直接结合如何影响mRNA特异性蛋白质输出.
- 为了确定eIF3-5' UTR相互作用的结合动机和功能相关性.
主要方法:
- 采用高通量方法来测量酵母eIF3与4252个基因中的5' UTRs的结合亲和力.
- 分析的重点是确定特定的结合动机,并将结合与核糖体密度和压力下翻译效率相关联.
主要成果:
- eIF3 特别与含有非结构化动机 AMAYAA 的 5' UTR 的子集结合.
- 通过eIF3结合的mRNA在生长细胞中表现出更高的核糖体密度.
- 这些eIF3结合的mRNA在特定的细胞应激条件下优先转化.
结论:
- 一个新型的转化增强剂类别通过eIF3结合5' UTRs的介导被确定.
- 这种相互作用为由核心启动因子调节的mRNA特定翻译程序提供了一种机制.
- 这些发现突出了eIF3在调节细胞应激反应中的基因表达中的作用.
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