Emergence of genetic sex determination in an environmentally sex-determined animal
Abstract
The evolution of genetic sex determination (GSD) from environmental sex determination (ESD) remains a fundamental issue in evolutionary biology. However, the mechanisms driving the transition, particularly in its earliest stages, are largely unknown. Here, we report a genetic variant in the ESD species, Daphnia pulex , in which structural variations on chromosome I have suppressed recombination. This suppression appears to have facilitated the accumulation of divergent features of two chromosome I haplotypes, resulting in differentiation of the linked sex-determining gene Dfh . This process has led to the emergence of a mixed-mating system, in which sex determination is jointly regulated by genetic and environmental factors, with ongoing divergence in chromosomal structure continuing to develop between the two haplotypes at the population level. These findings suggest that processes analogous to early sex-chromosome evolution are occurring in this ESD species, offering insights into the molecular mechanisms underlying the emergence of GSD.
Article Details
Journal Info
Proceedings of the National Academy of Sciences
National Academy of Sciences
Authors (15)
Wen Wei
Biodesign Center for Mechanisms of Evolution, Arizona State University
Man Lin
Biodesign Center for Mechanisms of Evolution, Arizona State University
Trent Bishop
Biodesign Center for Mechanisms of Evolution, Arizona State University
Ryan Shahriari
Biodesign Center for Mechanisms of Evolution, Arizona State University
Yue Hao
Logan Graham
Biodesign Center for Mechanisms of Evolution, Arizona State University
Bret L. Coggins
Department of Biological Sciences, Notre Dame University
Hannah Jee
Biodesign Center for Mechanisms of Evolution, Arizona State University
Emma Fonseca
Biodesign Center for Mechanisms of Evolution, Arizona State University
Swatantra Neupane
Division of Biological Sciences, University of Missouri
Li Wang
The Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital Zhengzhou China
Sen Xu
Division of Biological Sciences, University of Missouri
Erin Kim
Biodesign Center for Mechanisms of Evolution, Arizona State University
Michael Lynch
Biodesign Center for Mechanisms of Evolution
Zhiqiang Ye
Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, School of Life Sciences, Central China Normal University