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Natural selection and repeated patterns of molecular evolution following allopatric divergence.

ABSTRACT: Although geographic isolation is a leading driver of speciation, the tempo and pattern of divergence at the genomic level remain unclear. We examine genome-wide divergence of putatively single-copy orthologous genes (POGs) in 20 allopatric species/variety pairs from diverse angiosperm clades, with 16 pairs reflecting the classic eastern Asia-eastern North America floristic disjunction. In each pair, >90% of POGs are under purifying selection, and <10% are under positive selection. A set of POGs are under strong positive selection, 14 of which are shared by 10-15 pairs, and one shared by all pairs; 15 POGs are annotated to biological processes responding to various stimuli. The relative abundance of POGs under different selective forces exhibits a repeated pattern among pairs despite an ~10 million-year difference in divergence time. Species divergence times are positively correlated with abundance of POGs under moderate purifying selection, but negatively correlated with abundance of POGs under strong purifying selection.

SUBMITTER: Dong Y

PROVIDER: S-EPMC6744222 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Natural selection and repeated patterns of molecular evolution following allopatric divergence.

Dong Yibo Y Chen Shichao S Cheng Shifeng S Zhou Wenbin W Ma Qing Q Chen Zhiduan Z Fu Cheng-Xin CX Liu Xin X Zhao Yun-Peng YP Soltis Pamela S PS Wong Gane Ka-Shu GK Soltis Douglas E DE Xiang Qiu-Yun Jenny QJ

eLife 20190802

Although geographic isolation is a leading driver of speciation, the tempo and pattern of divergence at the genomic level remain unclear. We examine genome-wide divergence of putatively single-copy orthologous genes (POGs) in 20 allopatric species/variety pairs from diverse angiosperm clades, with 16 pairs reflecting the classic eastern Asia-eastern North America floristic disjunction. In each pair, >90% of POGs are under purifying selection, and <10% are under positive selection. A set of POGs ...[more]

PMID: 31373555

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Natural selection and repeated patterns of molecular evolution following allopatric divergence.

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Natural selection and repeated patterns of molecular evolution following allopatric divergence.

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