tRNA 形状是人类肠道中一个古老的 pyrrolysyl-tRNA 合成酶的标识元素
Natalie Krahn1, Jingji Zhang2, Sergey V Melnikov3
1Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA.
Nucleic acids research
|December 15, 2023
概括
研究人员确定了pyrrolysine整合的tRNA身份关键元素. 这些特征对于解-tRNA合成酶 (PylRS) 附着解至关重要,使得非正规氨基酸在蛋白质合成中的使用成为可能.
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:
- 转移RNAs (tRNAs) 对于蛋白质翻译至关重要,它将编码子与特定的氨基酸连接起来.
- 氨基酸-tRNA合成酶 (aaRS) 将正确的氨基酸连接到其相关的tRNA,这一过程对遗传代码的忠实性至关重要.
- 氨酸 (pyl) 是第22个氨基酸,通过专门的tRNA (tRNAPyl) 和合成酶 (PylRS) 配对结合在一起.
研究的目的:
- 研究特定的pyrrolysyl-tRNA合成酶 (MaPylRS) 与来自Candidatus Methanomethylophilus alvus的同类tRNA (tRNAPyl) 之间的相互作用的tRNA身份元素.
- 了解通过截断的PylRS (ΔpylSn) 介导的罗素合并的结构和功能基础.
主要方法:
- 氨基化试验被用来测量罗利与tRNAPyl.pyl的附着效率.
- 在体外翻译试验中评估了pyrrolysine在蛋白质中的功能性结合.
- 用分子动力学模拟来分析tRNA结构和灵活性.
主要成果:
- 在ΔpylSn tRNAPyl中确定了五个关键身份元素,这些元素对于MaPylRS的识别和活性是必要的.
- 在位置8缺少一个基和一个G-U摇摆对 (G28:U42) 显著影响了tRNA结构.
- 发现特定的G-C基对 (G3:C70和G5:C68) 有助于tRNA刚性.
结论:
- 这项研究阐明了特定的tRNA结构特征,这些特征决定了MaPylRS的识别,这对于氨酸的纳入至关重要.
- 了解这些身份元素可以了解非正规氨基酸结合的演变和机制.
- 这些发现有助于合成生物学和蛋白质工程的更广泛领域.
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