关键的cis-参数影响结构辅助RNA翻译 (START) 在真核生物中非AUG编码的启动
Antonin Tidu1, Fatima Alghoul1, Laurence Despons1
1Université de Strasbourg, Institut de Biologie Moléculaire et Cellulaire, Architecture et Réactivité de l'ARN, CNRS UPR9002, 2 allée Konrad Roentgen, F-67084 Strasbourg, France.
NAR genomics and bioinformatics
|June 12, 2024
概括
下游RNA结构可以通过阻断扫描核糖体来促进非AUG启动编码子的翻译启动. 这种结构辅助RNA翻译 (START) 机制在人类中很普遍,影响了替代翻译启动.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 生物信息学是一种生物信息学.
背景情况:
- 转化启动在真核生物中是一个复杂的,受调节的过程,涉及 cis 调节序列和转化作用因子,如真核生物启动因子 (eIF).
- 一个关键的步骤是43S预启动复合体扫描,用于启动核糖体组装和蛋白质合成的启动代码.
研究的目的:
- 调查下游二次结构在STructure-Assisted RNA翻译 (START) 机制中对AUG和非AUG启动的作用.
- 确定下游结构的最佳条件,以促进非AUG翻译的启动.
主要方法:
- 对二次结构稳定性和与非AUG编码子相对位置的分析.
- 在Homo sapiens中对替代翻译启动位点进行全基因组分析.
- 使用选定的上游开放阅读框架 (uORFs) 验证下游结构对翻译启动的影响.
主要成果:
- 下游的二次结构可以通过阻断43S粒子和稳定子-抗子配对来促进非AUG翻译启动.
- 这些结构所需的稳定性因不同细胞类型而异.
- 大约25%的人类替代翻译启动站点拥有能够促进START的下游结构,无论启动代码是什么.
结论:
- 下游RNA结构在调节翻译启动方面发挥着重要作用,特别是通过START机制对非AUG启动密码子起到重要作用.
- START机制是人类翻译领域的一个保存和广泛的监管策略.
- 了解START提供了对替代翻译和基因表达调节的见解.
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