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Using Phylogenetic Analysis to Investigate Eukaryotic Gene Origin
Published on: August 14, 2018
生殖系:细菌的一个非超热友的祖先
Céline Brochier1, Hervé Philippe
1Phylogénie, Bioinformatique et Génome, UMR 7622 CNRS, Université Pierre et Marie Curie, 9 quai St Bernard, 75005 Paris, France.
Nature
|May 17, 2002
概括
细菌的宇宙祖先可能不是热爱. 对核糖体RNA (rRNA) 序列的新分析表明,细菌的起源非超热友好,而浮游生物可能是最早的群体.
科学领域:
- 微生物进化过程中的微生物.
- 人类遗传学 是一个学科.
- 分子生物学分子生物学
背景情况:
- 生命的早期树,基于核糖体RNA (rRNA) 序列,建议超热友 (热爱) 生物体是第一个出现的.
- 这导致了这样的假设,即所有生命的宇宙祖先都是超热的.
- 然而,这种最初的解释一直在争论,因为在植物遗传学分析中存在潜在的偏见.
研究的目的:
- 通过更强大的方法重新评估细菌系谱.
- 确定超热友细菌是否确实代表了最早的分支血统.
- 为了确定最古老的细菌类.
主要方法:
- 重新分析来自不同细菌系的核糖体RNA (rRNA) 基因序列.
- 应用先进的遗传学方法来重建细菌生命树.
- 对分支秩序和祖先状态重建的比较分析.
主要成果:
- 超热性细菌系,如Aquificales和Thermotogales,在修订后的基因组中并不是最早的基因系.
- 数据表明,细菌的共同祖先可能不是超热的.
- 根据这项分析,植物菌群 (Planctomycetales) 似乎是最早的分离的细菌群.
结论:
- 细菌具有高热性普遍祖先的假设并未得到这一修订后的遗传学分析的支持.
- 细菌的祖先状态很可能是介质性或非高热性.
- 浮游生物 (Planctomycetales) 代表了理解早期细菌进化的重要血统.
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