在人类VEGF IRES中,G-四重复的RNA对于独立于帽子的翻译启动至关重要
Mark J Morris1, Yoichi Negishi, Cathy Pazsint
1Department of Chemistry and Biochemistry, Kent State University, Kent, Ohio 44242, United States.
Journal of the American Chemical Society
|November 26, 2010
概括
这项研究揭示了VEGF mRNA中的可切换RNA G-四重复.
科学领域:
- 分子生物学分子生物学
- 基因规则 基因规则
- 结构RNA结构RNA结构
背景情况:
- 在5'-UTR中的RNA G-四复合体通常会抑制封顶依赖的翻译.
- 在内部核糖体进入部位 (IRES) 介导的翻译中,G四重复的作用较少被理解.
研究的目的:
- 为了研究一个富G元素在人类VEGF mRNA的5'-UTR中的作用.
- 要确定这个元素是否形成G-四重复结构,以及它在翻译启动中的功能.
主要方法:
- 结构分析以确定G-四重复形成.
- 功能性测试以评估翻译启动.
- 突变性研究探讨了序列结构功能关系.
主要成果:
- 在VEGF mRNA 5'-UTR.中展示了一个"可切换"的RNA G-四重复结构.
- 展示了这个G-quadruplex对于IRES介导的翻译启动至关重要.
- 确定了影响翻译调节的依赖序列的构造转换.
结论:
- 这是关于构造灵活的RNA G-四重复的第一份报告,对于IRES介导的翻译至关重要.
- 在转化启动过程中,VEGF mRNA G-quadruplex 具有可调节的调控作用.
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