1. Sexual antagonism drives the displacement of polymorphism across gene regulatory cascades
- Author
-
Alexander J. Stewart, Max Reuter, and Mark S. Hill
- Subjects
Male ,0106 biological sciences ,Evolution ,Population ,Locus (genetics) ,Biology ,010603 evolutionary biology ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Gene expression ,Genetic variation ,Animals ,Gene Regulatory Networks ,Allele ,education ,Evolutionary dynamics ,Gene ,030304 developmental biology ,General Environmental Science ,Regulation of gene expression ,Sex Characteristics ,0303 health sciences ,education.field_of_study ,Binding Sites ,Polymorphism, Genetic ,General Immunology and Microbiology ,Reproduction ,General Medicine ,Mating Preference, Animal ,Adaptation, Physiological ,Sexual dimorphism ,Evolutionary biology ,Female ,General Agricultural and Biological Sciences - Abstract
Males and females have different reproductive roles and are often subject to contrasting selection pressures. This sexual antagonism can lead, at a given locus, to different alleles being favoured in each sex and, consequently, to genetic variation being maintained in a population. Although the presence of sexually antagonistic (SA) polymorphisms has been documented across a range of species, their evolutionary dynamics remain poorly understood. Here, we study SA selection on gene expression, which is fundamental to sexual dimorphism, via the evolution of regulatory binding sites. We show that for sites longer than 1 nucleotide, expression polymorphism is maintained only when intermediate expression levels are deleterious to both sexes. We then show that, in a regulatory cascade, expression polymorphism tends to become displaced over evolutionary time from the target of SA selection to upstream regulators. Our results have consequences for understanding the evolution of sexual dimorphism, and provide specific empirical predictions for the regulatory architecture of genes under SA selection.
- Published
- 2019