通过m6进行翻译解码的调制 mRNA的修改
Sakshi Jain1, Lukasz Koziej2, Panagiotis Poulis1
1Max Planck Institute for Multidisciplinary Sciences, Göttingen, 37077, Germany.
Nature communications
|August 8, 2023
概括
N6-甲基氨酸 (m6A) 修改了mRNA,影响了细菌的翻译. 这种m6A修饰通过破坏复合体的稳定和增加tRNA掉落来阻碍核糖体解码,影响蛋白质合成.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 遗传学 是一个遗传学.
背景情况:
- N6-甲基氨酸 (m6A) 是一种流行的mRNA修饰,影响mRNA代谢.
- 已知mRNA编码区域内的m6A可以抑制翻译延长.
研究的目的:
- 阐明m6A在细菌翻译系统中调节解码的机制.
- 为了研究m6A在翻译过程中对核糖体-mRNA-tRNA相互作用的影响.
主要方法:
- 使用了快速动力学,单分子福斯特共振能量转移 (smFRET) 和单粒子冷电子显微镜 (cryo-EM) 的组合.
- 分析了核糖体复合体的稳定性和tRNA下降率在m6A的存在和缺席下.
- 检查了mRNA编码子构造及其在氨基酸-tRNA结合后的重塑.
主要成果:
- m6A不会阻碍氨基酸tRNA与核糖体的初始结合.
- 由于复合体稳定性降低和tRNA掉落增加,在m6A的存在下,较少的核糖体成功完成解码.
- m6A倾向于动态的mRNA编码子构造,这些构造与正规的编码子-反编码子配对不太兼容,并且被核糖体拒绝.
结论:
- m6A的修改,即使在直接的子-子相互作用部位之外,也可能干扰基配对和核糖体识别.
- 这些相互作用通过影响解码忠实性和复杂稳定性来调节翻译效率.
- 这项研究揭示了一个新的机制,即mRNA修改调节基因表达在翻译水平.
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