欧核生物抗病毒免疫蛋白通过融合,水平转移和古代遗传产生
Edward M Culbertson1, Tera C Levin1
1University of Pittsburgh, Department of Biological Sciences.
bioRxiv : the preprint server for biology
|July 10, 2023
概括
细胞天生的免疫是古老的和动态的,蛋白质是从早期祖先遗传的,并通过细菌的水平基因转移获得的. 这项研究揭示了像Viperins和cGAS这样的关键抗病毒蛋白的进化历史.
科学领域:
- 进化生物学是进化的生物学.
- 免疫学 免疫学 免疫学
- 微生物学 微生物学
背景情况:
- 动物具有天生的免疫蛋白来检测病毒感染.
- 一些哺乳动物的抗病毒蛋白类似于细菌的抗菌素蛋白,这表明在整个生命中共享天生的免疫力.
- 动物和细菌免疫蛋白之间的进化联系往往被进化距离所掩盖.
研究的目的:
- 为了澄清三种先天免疫家族 (CD-NTases,STINGs,Viperins) 在真核生物中的进化关系.
- 研究这些免疫蛋白的起源和进化轨迹.
- 了解横向基因转移在形成真核生物天生的免疫力中的作用.
主要方法:
- 在真核生物中对蛋白质多样性的深度采样.
- 对CD-NTase,STING和Viperin蛋白家族的遗传学分析.
- 比较基因组学来追踪基因转移事件.
主要成果:
- 维培林和OAS家族CD-NTases是古老的,早于最后一个真核生物共同祖先.
- 至少有四次来自细菌的横向基因转移事件将新的免疫基因引入了真核生物.
- 通过HGT产生了明显的真核CD-NTase超级家族 (Mab21,包括cGAS和eSMODS),cGAS通过动物特异性的重复而多样化.
- 毒刺在细菌和真核生物中通过融合域混合进化.
结论:
- 细胞天生的免疫是一个动态的系统,建立在古老的基础上,并由细菌的抗菌素基因增强.
- 横向基因转移一再为真核生物提供了新的抗病毒能力.
- 了解这些进化过程对于理解先天免疫的多样性和功能至关重要.
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