抗病毒Mx蛋白具有古老的起源,在真核生物中广泛分布
Caroline A Langley1,2,3, Peter A Dietzen1,2,3, Michael Emerman2,3
1Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, WA 98195.
概括
对于抗病毒防御至关重要的Mx蛋白质起源于真核生物进化的早期,早于脊椎动物的干扰素系统. 这些Dynamin超级家族蛋白质在各种生命形式中表现出古老的病毒和抗病毒作用.
科学领域:
- 进化生物学是进化的生物学.
- 病毒学 病毒学
- 细胞动态 细胞动态
背景情况:
- Mx蛋白赋予广泛的抗病毒活性.
- Mx蛋白属于Dynamin蛋白超级家族 (DSP),参与细胞动力学.
- Mx蛋白的进化起源在很大程度上是未知的.
研究的目的:
- 研究Mx蛋白的进化起源和古代功能.
- 为了确定Mx蛋白是否早于脊椎动物干扰素系统.
- 探索Mx蛋白,其他Dynamin超级蛋白和病毒元素之间的关系.
主要方法:
- 通过扩展分类学抽样进行全面的族群基因组分析.
- 在真核生物和病毒中对Dynamin超级家族蛋白质的基因分析.
- 蛋白质家族和进化史的比较分析.
主要成果:
- 在脊椎动物中,Mx蛋白早于干扰素信号系统.
- 在真核生物中,一个古老的,单体的Dynamin超级家族蛋白质系包括脊椎动物和无脊椎动物的Mx蛋白质,真菌的MxF蛋白质和植物/藻类的Dynamin 4A/4C蛋白质.
- 胺超级家族蛋白质被发现与病毒蛋白质交织在一起,表明反复复发的病毒基因获取.
- 类似Mx的蛋白质可能可以追溯到Eukarya的起源.
结论:
- 超级Dynamin家族具有悠久的进化历史,与病毒和抗病毒功能交织在一起.
- Mx蛋白具有古老的起源和作用,可以追溯到复杂的免疫系统之前.
- 宿主Dynamin超级家族蛋白质的病毒盗窃在整个进化过程中发生了多次.
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