Dataset Information

Dead-End Hybridization in Walnut Trees Revealed by Large-Scale Genomic Sequence Data.

ABSTRACT: Although hybridization plays a large role in speciation, some unknown fraction of hybrid individuals never reproduces, instead remaining as genetic dead-ends. We investigated a morphologically distinct and culturally important Chinese walnut, Juglans hopeiensis, suspected to have arisen from hybridization of Persian walnut (J. regia) with Asian butternuts (J. cathayensis, J. mandshurica, and hybrids between J. cathayensis and J. mandshurica). Based on 151 whole-genome sequences of the relevant taxa, we discovered that all J. hopeiensis individuals are first-generation hybrids, with the time for the onset of gene flow estimated as 370,000 years, implying both strong postzygotic barriers and the presence of J. regia in China by that time. Six inversion regions enriched for genes associated with pollen germination and pollen tube growth may be involved in the postzygotic barriers that prevent sexual reproduction in the hybrids. Despite its long-recurrent origination and distinct traits, J. hopeiensis does not appear on the way to speciation.

SUBMITTER: Zhang WP

PROVIDER: S-EPMC8760940 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Dead-End Hybridization in Walnut Trees Revealed by Large-Scale Genomic Sequence Data.

Zhang Wei-Ping WP Cao Lei L Lin Xin-Rui XR Ding Ya-Mei YM Liang Yu Y Zhang Da-Yong DY Pang Er-Li EL Renner Susanne S SS Bai Wei-Ning WN

Molecular biology and evolution 20220101 1

Although hybridization plays a large role in speciation, some unknown fraction of hybrid individuals never reproduces, instead remaining as genetic dead-ends. We investigated a morphologically distinct and culturally important Chinese walnut, Juglans hopeiensis, suspected to have arisen from hybridization of Persian walnut (J. regia) with Asian butternuts (J. cathayensis, J. mandshurica, and hybrids between J. cathayensis and J. mandshurica). Based on 151 whole-genome sequences of the relevant t ...[more]

PMID: 34687315

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Dataset Information

Dead-End Hybridization in Walnut Trees Revealed by Large-Scale Genomic Sequence Data.

Publications

Dead-End Hybridization in Walnut Trees Revealed by Large-Scale Genomic Sequence Data.

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