证据表明,真核生物和真核细胞原核生物是直接的亲属.
1Molecular Biology Institute, University of California, Los Angeles 90024.
Science (New York, N.Y.)
|July 3, 1992
概括
由于基因分歧,真核生物的起源仍然不清楚. 通过比较延长因子EF-1α基因,在真核生物和真核细胞中发现了一个独特的11-氨基酸段,这表明真核细胞是真核生物最接近的细菌亲属.
科学领域:
- 分子生物学分子生物学
- 进化生物学是进化的生物学.
- 基因组学就是基因组学.
背景情况:
- 很难确定真核生物的进化历史和遗传学起源.
- 细胞核基因与 prokaryotic 基因发生了显著的分歧,使进化分析复杂化.
研究的目的:
- 为了研究真核生物和原核生物之间的遗传关系.
- 为了识别分子标记,可以揭示真核细胞的起源.
主要方法:
- 跨多种生物体的延长因子EF-1α基因的比较序列分析.
- 特定氨基酸序列段的识别和比较,包括11-氨基酸插入.
主要成果:
- 在真核生物的EF-1α序列中发现了一个独特的11-氨基酸段.
- 这11个氨基酸部分也存在于幼细胞 (极度热友,硫代谢细菌) 中.
- 在所有其他细菌系和相关的类似基因 (EF-2,IF-2) 中,插入物不存在.
结论:
- 共有的11个氨基酸插入物的存在强烈地表明了密切的进化关系.
- 细胞代表了基于EF-1α基因序列数据的真核生物的最近存活的亲属 (姐妹分类).
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