线

Eric Bazin1, Sylvain Glémin, Nicolas Galtier

  • 1CNRS UMR 5171-Génome, Populations, Interactions, Adaptation-Université Montpellier 2 34095 Montpellier Cedex 5, France.

Science (New York, N.Y.)
|April 29, 2006
PubMed
概括

与预期相反,动物的线粒体DNA (mtDNA) 多样性与物种丰富或生态不相关. 反复的适应性进化,而不是中性过程,解释了这种模式,影响了生物多样性和保护相关性.

相关概念视频

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Mutation, Gene Flow, and Genetic Drift

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Conservation of Small Populations02:04

Conservation of Small Populations

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Gene Evolution - Fast or Slow?02:05

Gene Evolution - Fast or Slow?

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Genome Size and the Evolution of New Genes03:21

Genome Size and the Evolution of New Genes

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Genome Size and the Evolution of New Genes03:21

Genome Size and the Evolution of New Genes

While every living organism has a genome of some kind (be it RNA, or DNA), there is considerable variation in the sizes of these blueprints. One major factor that impacts genome size is whether the organism is prokaryotic or eukaryotic. In prokaryotes, the genome contains little to no non-coding sequence, such that genes are tightly clustered in groups or operons sequentially along the chromosome. Conversely, the genes in eukaryotes are punctuated by long stretches of non-coding sequence.
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The genomes of eukaryotes are punctuated by long stretches of sequence which do not code for proteins or RNAs. Although some of these regions do contain crucial regulatory sequences, the vast majority of this DNA serves no known function. Typically, these regions of the genome are the ones in which the fastest change, in evolutionary terms, is observed, because there is typically little to no selection pressure acting on these regions to preserve their sequences.
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