ZW and XY Sex Chromosomes Drive Rapid and Distinctive Evolution of Sex-Biased Gene Expression.

ABSTRACT: Cichlids are a textbook model system of adaptive radiation and a fascinating example of rapid sex chromosome evolution. Yet in these fish, as in most other taxa, the mechanisms causing sex chromosome turnover and the subsequent impact thereof are unknown. Sexual antagonism was long thought to be a driver of sex chromosome emergence, but experimental support remains scarce. Here, we show that sex-biased genes, often used as indicators of sexual antagonism, are enriched in three different sex chromosome systems of Lake Tanganyika cichlid species that diverged less than 4 million years ago. Moreover, gene expression is feminised in species that transitioned from an XY to a ZW system on the same chromosome. This is achieved by gain of female-biased genes, increase of female sex-bias as well as

SUBMITTER: Hsiung K 

PROVIDER: S-EPMC12617055 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature