三个鱼基因组揭示了鱼类的祖先进化模式
Richard E Green1, Edward L Braun2, Joel Armstrong3
1Department of Biomolecular Engineering, University of California, Santa Cruz, CA 95064, USA. ed@soe.ucsc.edu david.a.ray@ttu.edu.
概括
鱼基因组显示出异常缓慢的进化,这表明这种特征早于鸟类和恐龙. 这项研究重建了类动物的祖先.
科学领域:
- 进化生物学是进化的生物学.
- 基因组学就是基因组学.
- 进行比较的基因组学.
背景情况:
- 包括鱼,恐龙和鸟类在内的类动物经历了显著的多样化.
- 了解推动这种多样化的基因组变化需要从关键血统中比较基因组数据.
研究的目的:
- 为了提供基因组上下文,为类动物的多样化.
- 为了研究鱼的进化速率和种群历史.
- 为了重建类动物共同祖先的基因组.
主要方法:
- 生成了三种鱼物种的基因组草案:美国鱼,盐水鱼和印度鱼.
- 分析了多个层面的基因组进化:核酸替代,indels,可转移元素,基因家族和合成.
- 综合鱼基因组数据与已发表的鸟类和乌基因组.
主要成果:
- 在所有分析水平的鱼中观察到异常缓慢的基因组进化.
- 推断,缓慢的基因组进化很可能存在于类动物的共同祖先中,而快速进化是鸟类的衍生性质.
- 分析了鱼异构性,这表明在普莱斯托时代减少了种群规模.
- 重建了类动物共同祖先的部分基因组.
结论:
- 鱼的基因组保存得非常出色,这表明分子进化的速度很慢.
- 祖先的龙可能拥有缓慢进化的基因组,与鸟类观察到的快速进化形成鲜明对比.
- 重建的类动物祖先基因组作为未来进化研究的宝贵资源.
相关概念视频
Convergent Evolution
34.9K
Evolution shapes the features of organisms over time, ensuring that they are suited for the environments in which they live. Sometimes, selection pressure leads to the rise of similar but unrelated adaptations in organisms with no recent common ancestors, a process known as convergent evolution.
34.9K
Evolutionary Relationships through Genome Comparisons
7.3K
Genome comparison is one of the excellent ways to interpret the evolutionary relationships between organisms. The basic principle of genome comparison is that if two species share a common feature, it is likely encoded by the DNA sequence conserved between both species. The advent of genome sequencing technologies in the late 20th century enabled scientists to understand the concept of conservation of domains between species and helped them to deduce evolutionary relationships across diverse...
7.3K
Synteny and Evolution
4.1K
John H. Renwick first coined the term “synteny” in 1971, which refers to the genes present on the same chromosomes, even if they are not genetically linked. The species with common ancestry tend to show conserved syntenic regions. Therefore, the concept of synteny is nowadays used to describe the evolutionary relationship between species.
Around 80 million years ago, the human and mice lineages diverged from the common ancestor. During the course of evolution, the ancestral...
Around 80 million years ago, the human and mice lineages diverged from the common ancestor. During the course of evolution, the ancestral...
4.1K
Phylogeny
64.8K
Phylogeny is concerned with the evolutionary diversification of organisms or groups of organisms. A group of organisms with a name is called a taxon (singular). Taxa (plural) can span different levels of the evolutionary hierarchy. For instance, the group containing all birds is a taxon (comprising the class Aves), and the group of all species of daisies (the genus Bellis) is a taxon. Phylogenies can likewise include just one genus (i.e., depict species relationships) or span an entire kingdom.
64.8K
Eukaryotic Evolution
44.0K
The endosymbiont theory is the most widely accepted theory of eukaryotic evolution; however, its progression is still somewhat debated. According to the nucleus-first hypothesis, the ancestral prokaryote first evolved a membrane to enclose DNA and form the nucleus. Conversely, the mitochondria-first hypothesis suggests that the nucleus was formed after endosymbiosis of mitochondria.
Contrary to the endosymbiont theory, the eukaryote-first hypothesis proposes that the simpler prokaryotic and...
Contrary to the endosymbiont theory, the eukaryote-first hypothesis proposes that the simpler prokaryotic and...
44.0K
What is Evolutionary History?
45.2K
Scientists record evolutionary history by analyzing fossil, morphological, and genetic data. The fossil record documents the history of life on Earth and provides evidence for evolution. However, both fossil and living organisms offer evidence that outlines Earth’s evolutionary history.
45.2K


