在陆地牛和牛中复制的霍克斯基因集群的进化
Finn McHale1, Peter O Mulhair2, Peter W H Holland1
1Department of Biology, University of Oxford, Oxford, UK.
概括
陆地牛和 (Stylommatophora) 显示了Hox基因集群在古代基因组重复后如何演变. 它们的基因组织揭示了类似于脊椎动物在重复后的霍克斯基因进化模式.
科学领域:
- 基因组学就是基因组学.
- 进化生物学 进化生物学
- 发育生物学 发展生物学
背景情况:
- 包含陆地牛和牛的类型Stylommatophora在它们的进化历史上经历了一次重要的基因组复制事件.
- 了解无脊椎动物中后重复的霍克斯基因集群进化,为记录完善的脊椎动物重复提供了一个比较模型.
研究的目的:
- 在祖先基因组复制后,研究陆地类动物中Hox基因集群的组织和进化.
- 为了比较Hox基因集群在Stylommatophora中的进化轨迹与脊椎动物中的进化轨迹.
主要方法:
- 用基因组数据分析来研究霍克斯基因组织.
- 用聚合酶链反应 (PCR) 来实验验证基因组发现.
主要成果:
- 分析了10种Stylommatophora和1种相关物种,在所有采样种群中揭示了碎片化的Hox基因集群.
- 在染色体中分散的HoxA群通常含有9个基因 (8个在子中),而在另一个染色体上的HoxB群通常有7个基因 (6个在非洲大陆牛中).
- 没有分析的物种保留了11个祖先的Hox基因的完整补充,这表明显著的基因损失和重排.
结论:
- 在Stylommatophora中复制的霍克斯基因的保留模式与在复制的脊椎动物霍克斯基因集群中观察到的具有显著相似之处.
- 这项研究强调了在基因复制事件后,在多样化的动物血统中,Hox基因集群组织中的融合进化策略.
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