所有肺鱼的基因组提供了基因组扩张和四足动物进化信息
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在PubMed上查看摘要
概括
此摘要是机器生成的。肺鱼的基因组揭示了鱼-四足动物的转变. 在Lepidosiren悖论中,大量的基因组扩张与可转移元素抑制的减少有关,影响了四肢的发育.
科学领域
- 进化生物学
- 基因组学
- 发育生物学
背景情况
- 肺鱼对于理解脊椎动物从水到陆的转变至关重要.
- 它们的基因组提供了关于纪鱼类-四足动物过渡的分子见解.
研究的目的
- 对非洲 (Protopterus annectens) 和南美 (Lepidosiren paradoxa) 肺鱼的基因组进行新的测序和分析.
- 调查肺鱼进化的基因组基础和鱼-四足动物的转变.
主要方法
- 整个基因组测序的Protopterus和莱皮多西伦悖论.
- 与Neoceratodus forsteri和其他脊椎动物进行基因组比较分析.
- 对可转移元素活动和基因调节的分析.
主要成果
- 莱皮多西伦悖论基因组是测序的最大动物基因组 (91 Gb),主要是由于扩展的基因间区域和高重复含量的内基因 (90%).
- 由于仍然活跃的可转移元素 (TE),肺鱼基因组正在积极扩张,而Lepidosiren在过去1亿年中呈现出快速扩张.
- 基因组扩张与抑制TE的基因,如PIWI相互作用RNA和特定的指/KRAB域蛋白的减少表达相关.
- 尽管有TE活动,肺鱼染色体保留了祖先四足动物型的特征.
- 在Neoceratodus的肢体状中,存在1亿年左右的表型静止与Lepidosiren-Protopterus祖先的副次肢体损失形成鲜明对比,这与声波刺肢体特异性增强剂的损失有关.
结论
- 肺鱼基因组提供了一个独特的窗口, 了解鱼类-四足动物转变背后的分子和发育事件.
- 肺鱼的巨大基因组大小和活跃的可转移元素为基因组进化动态提供了洞察力.
- 一些肺鱼系的四肢状附属体的丧失与声音等关键发育基因的调节性变化有关.
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