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病毒样特征和内在无序区域的进化在逆转移素衍生的哺乳动物基因中
Rachele Cagliani1, Diego Forni1, Alessandra Mozzi1
1Scientific Institute IRCCS E. MEDEA, Computational Biology Unit, Bosisio Parini 23842, Italy.
Molecular biology and evolution
|August 5, 2024
概括
来自逆转移体的哺乳动物基因保留了类似病毒的特征. 进化有利于编程的核糖体框架转移和内在无序的区域,影响蛋白质功能和进化速率.
科学领域:
- 进化生物学是进化的生物学.
- 分子进化是分子进化的过程.
- 基因组学就是基因组学.
背景情况:
- 哺乳动物的基因可以起源于逆转移体,后者是移动的遗传元素.
- 一些由逆转移素衍生的蛋白质表现出类似病毒的特征,包括通过 -1 编程的核糖体框架转移进行自我处理和替代性异型生成.
- 这些类似病毒的特征的进化历史和功能含义尚未完全理解.
研究的目的:
- 为了研究28个逆转移素衍生的哺乳动物基因中的病毒状特征的演化.
- 分析了 -1 编程核糖体框架转移的保护和功能影响.
- 探索这些基因内在无序区域,进化速率和积极选择之间的关系.
主要方法:
- 定量分子进化分析,包括同义替代率分析.
- 对蛋白质性质的生物物理分析,专注于内在无序的区域.
- 比较基因组学研究序列模式和哺乳动物 ортолог之间的积极选择.
主要成果:
- 在哺乳动物中,编程的-1核糖体框架转移机制在PEG10,PNMA3和PNMA5中被保存,产生替代蛋白质.
- 这些基因,特别是在灵长类动物中,显示出积极选择的证据,其中一个部位影响了PNMA5囊上的B细胞表位.
- 具有较高内在无序区域含量的逆转移子衍生蛋白更快地进化;正选择针对这些区域,影响后翻译修饰和蛋白质结构.
结论:
- 类似病毒的特征,包括编程的核糖体框架转移,在哺乳动物逆转移素衍生的基因中被进化保存.
- 积极选择对这些蛋白质内的内在无序区域起作用,影响它们的生物物理性质,进化速率,并可能影响它们的功能.
- 这项研究提供了对逆转移素衍生的基因进化轨迹的见解,并突出了内在无序区域在适应中的作用.
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