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Updated: Jul 4, 2025

Toeprinting Analysis of Translation Initiation Complex Formation on Mammalian mRNAs

Toeprinting Analysis of Translation Initiation Complex Formation on Mammalian mRNAs

Published on: May 10, 2018

在tRNA中的C²-甲基氨酸促进了蛋白质翻译,通过促进双重m²A-tRNA依赖的编码子的解码

Hong-Chao Duan¹, Chi Zhang¹, Peizhe Song¹

¹Synthetic and Functional Biomolecules Center, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.

Nature communications

|February 3, 2024

概括

N2-甲基氨酸 (m2A) RNA修饰在植物叶绿体和细胞质中发现. 这种修改通过促进放松的tRNA构造来提高翻译效率,揭示了植物基因表达调节的新层.

科学领域:

分子生物学分子生物学
植物科学植物科学
遗传学遗传学是一个

背景情况:

N2-甲基氨酸 (m2A) 是一种在细菌中发现的RNA修饰,由RlmN甲基转移酶安装.
在植物tRNA和rRNA中m2A的功能和患病率在很大程度上仍未被描述.

研究的目的:

为了研究植物RNA中m2A修饰的存在和功能.
识别特定于植物的m2A甲基转移酶及其标.
阐明m2A在植物器官和细胞质内翻译调节中的作用.

主要方法:

在各种植物物种中识别m2A修饰的tRNA和rRNA.
负责m2A装置的阿拉比多普西斯塔利亚纳甲基转移酶 (RLMNL1,RLMNL2,RLMNL3) 的表征.
分析m2A对tRNA构造和翻译效率的影响.

主要成果:

在多种植物物种中,在质细胞rRNA,质细胞tRNA和细胞质tRNA中发现了m2A修饰.
六个质细胞tRNA和两个细胞质tRNA被确定为m2A修饰的目标.
阿拉比多普西斯 RLMNL1,RLMNL2和RLMNL3分别被描述为叶绿体rRNA,叶绿体tRNA和细胞质tRNA的甲基转移酶.
在位置37 (m2A37) 的m2A被证明可以诱导放松的tRNA构造,提高特定编码子的翻译效率.

结论:

m2A是植物中保存的RNA修饰,存在于叶绿体和细胞质中.
m2A在优化翻译效率方面发挥着至关重要的作用,因为它促进了编码子解码.
这项研究揭示了植物中通过m2A修饰调节的转录后基因调节的新机制.

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