A role for a neo-sex chromosome in stickleback speciation

Article

关键词: REPRODUCTIVE ISOLATION;    CICHLID FISH;    THREESPINE STICKLEBACKS;    SEGREGATION DISTORTION;    SYMPATRIC SPECIATION;    Y-CHROMOSOME;    EVOLUTION;    DROSOPHILA;    SELECTION;    GASTEROSTEUS;   

DOI  :  10.1038/nature08441

来源: SCIE

【 摘 要 】

Sexual antagonism, or conflict between the sexes, has been proposed as a driving force in both sex-chromosome turnover and speciation. Although closely related species often have different sex-chromosome systems, it is unknown whether sex-chromosome turnover contributes to the evolution of reproductive isolation between species. Here we show that a newly evolved sex chromosome contains genes that contribute to speciation in threespine stickleback fish (Gasterosteus aculeatus). We first identified a neo-sex chromosome system found only in one member of a sympatric species pair in Japan. We then performed genetic linkage mapping of male-specific traits important for reproductive isolation between the Japanese species pair. The neo-X chromosome contains loci for male courtship display traits that contribute to behavioural isolation, whereas the ancestral X chromosome contains loci for both behavioural isolation and hybrid male sterility. Our work not only provides strong evidence for a large X-effect on reproductive isolation in a vertebrate system, but also provides direct evidence that a young neo-X chromosome contributes to reproductive isolation between closely related species. Our data indicate that sex-chromosome turnover might have a greater role in speciation than was previously appreciated.

【 授权许可】

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