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MHC IIB的演变多样性跨鱼鱼辐射

Carlos Lozano-Martín¹, Seraina E Bracamonte¹, Marta Barluenga¹

¹Museo Nacional de Ciencias Naturales, CSIC, Madrid, Spain.

Genome biology and evolution

|June 14, 2023

概括

主要基因相容性复合 (MHC) 基因在鱼中显示出跨大陆的广泛相似性,可能是由于跨物种的多态性. 这表明古老的MHC等位基因对各种物种的免疫适应至关重要.

科学领域:

进化生物学是进化的生物学.
免疫遗传学免疫遗传学
分子生态学分子生态学

背景情况:

主要基因相容性复合体 (MHC) 基因具有高度多态性,对于脊椎动物的适应性免疫是必不可少的.
MHC等位基系谱和物种系谱之间的不一致性很常见,通常归因于由寄生虫介导的平衡选择驱动的跨物种多态 (TSP).
对MHC等位基因相似性的替代解释包括聚合或内向等后分类机制.

研究的目的:

调查推动非洲和新热带鱼辐射中MHCIIB类多样性的进化机制.
为了确定不同鱼谱系中观察到的MHC等位基因相似性的原因.
探讨TSP与聚合或内向等后分类机制之间的作用.

主要方法:

综合审查可用的MHC IIBDNA序列数据从鱼.
在不同的类辐射中对MHC IIB等位基因序列进行比较分析.
探索进化模式,以区分TSP,收和内进.

主要成果:

在不同大陆的鱼物种中发现了广泛的MHC IIB等位基因相似性.
观察到的等位基因相似性强烈表明跨物种多态性 (TSP).
在来自不同大陆的物种中,在MHC中也发现了共同的功能相似性.

结论:

长期维持特定的MHC等位基因及其共享功能意味着它们在免疫适应中的关键作用.
某些MHC变异可能是适应各种环境的必要条件,即使在数百万年的物种分歧之后.
这项研究强调了MHC在脊椎动物免疫反应中的进化意义,跨越了广的地质时间尺度.

关键词:

适应性辐射适应性的辐射平衡选择选择的选择.融合进化的趋同.功能上的超级类型.主要的组织相容性复杂.

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