Simón D. Sun, Jessica Tollkühn
Sex hormones are a primary source for biological variation throughout the animal kingdom, from morphological characteristics to elaborate courtship displays. These steroids, such as estrogens and androgens, are indispensable for the development and function of the nervous tissues that mediate sex differences in reproduction, metabolism, and social behavior. Crucially, the cognate receptors for sex hormones are transcription factors that bind DNA to regulate expression of nearby genes. Although there has been substantial recent progress in dissecting the neural circuitry that regulates sex-differential behaviors, there is a dearth of understanding regarding how sex hormones act on this circuitry to modulate behavior. Here, we focus on the transcriptional actions of sex hormone receptors and the functions of their target genes, particularly voltage-gated ion channels. We put forth a framework in which sex hormone receptor modulation of gene expression affects cell activity states across interconnected brain regions, leading to emergent social behaviors.