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Updated: May 11, 2025

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Xenopus laevis as a Model to Identify Translation Impairment
Published on: September 27, 2015
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一个金属离子介导的功能二分法在翻译质量控制过程中编码了可塑性
Jotin Gogoi1, Komal Ishwar Pawar1, Koushick Sivakumar1,2
1CSIR-Centre for Cellular and Molecular Biology, Hyderabad, 500007, Telangana, India.
Nature communications
|April 16, 2025
概括
蛋白质校对中的离子确保了遗传密码的准确性. 这项研究揭示了这些离子在压力下如何保护翻译忠实性,在数十亿年的时间里,在阿兰-tRNA合成酶和三-tRNA合成酶之间功能上有所分歧.
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:
- 遗传代码翻译需要校对,以进行质量控制和应激适应.
- 阿拉尼尔-tRNA合成酶 (AlaRS-Ed) 和三尼尔-tRNA合成酶 (ThrRS-Ed) 编辑域共享一个共同的结构和Zn2+结合基因.
- 这些领域的功能差异,特别是金属离子的使用,是关键的.
研究的目的:
- 阐明AlaRS-Ed和ThrRS-Ed校对模块的操作二分法的结构和功能基础.
- 了解Zn2+在保护对反应性氧物种 (ROS) 的翻译忠实性的作用.
- 调查这些校对机制的进化分歧.
主要方法:
- 对tRNA合成酶编辑域的结构分析.
- 生物化学测试以评估酶活性和忠实性.
- 进化论的比较分析.
主要成果:
- 在AlaRS-Ed中的Zn2+保护ROS,确保细胞存活的Ala-codons的高保真翻译.
- ThrRS-Ed活动由ROS调节,允许对Thr-codon误译的耐受性.
- 一个单一的氨基酸变化解释了AlaRS-Ed和ThrRS-Ed之间的功能差异.
结论:
- 蛋白质质量控制与可调节的金属结合部位的氧化还原信号集成.
- 通过tRNA合成酶对金属离子利用的进化分歧影响了在压力下细胞的健康状况.
- 这项研究突出了自从最后的普世共同祖先 (LUCA) 以来,适应遗传翻译环境条件的保存机制.
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