域崩和活性位点切除产生广泛的动物线粒体-tRNA合成酶
Bastiaan de Potter1,2, Ingrid Vallee3, Noelia Camacho1
1Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Catalonia, Spain.
Nucleic acids research
|August 28, 2023
概括
氨基酸-tRNA合成酶 (aaRS) 对遗传密码至关重要. 一项新研究揭示了甲基动物线粒体SerRS通过域崩和活性位移而进化,而不是域添加,创造新的功能.
科学领域:
- 生物化学 生化学
- 分子生物学分子生物学
- 进化生物学 进化生物学
背景情况:
- 氨基酸-tRNA合成酶 (aaRS) 是必不可少的酶,它将氨基酸附着到相应的tRNA,这是蛋白质合成和遗传密码的基础.
- 细胞的aaRSs已经进化出具有额外域和拼接变体的复杂结构,导致超越氨基化之外的多样化的细胞功能.
- 异构体甲基动物线粒体SerRS代表了典型的aARS架构的一个不寻常的例外.
研究的目的:
- 为了研究异种类型的甲基动物线粒体SerRS.的进化起源.
- 了解结构和功能上的适应,使其与其同质体祖先有所区别.
- 阐明这种酶获得新型,正交的功能的机制.
主要方法:
- 对同位体和异位体 SerRS 的比较结构分析.
- 生物化学试验以评估氨基化活性和基质特异性.
- 功能性研究以确定和描述酶的直角作用.
主要成果:
- 异种类型的甲基动物线粒体SerRS从同种类型的祖先通过一个子单元的域崩和另一个子单元的活性位点切除进化.
- 这种独特的进化路径保留了必不可少的氨基化活性,同时为直角函数产生了新的表面.
- 这些结构修改直接与酶新发现的细胞作用有关.
结论:
- 甲基动物线粒体SerRS为酶进化提供了一个新的模型,证明了通过域损失和切除而不是添加的重定位.
- 这项研究揭示了古代酶家族如何获得新功能的新范式.
- 这些发现扩大了我们对aARS酶在细胞生物学中扮演的各种角色的理解.
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