SRA

Changes in gene expression represent an important source for phenotypical innovation. Yet, how such changes emerge and impact the evolution of traits remains elusive. Here, we explore the molecular mechanisms associated with the development of masculinizing ovotestes in female moles. By performing comparative analyses of epigenetic and transcriptional data in mole and mouse, we identified SALL1 as a co-opted gene for the formation of testicular tissue in mole ovotestes. Chromosome conformation capture analyses highlight a striking conservation of the 3D organization at the SALL1 locus, but a prominent evolutionary turnover of enhancer elements. Interspecies reporter assays support the capability of mole-specific enhancers to activate transcription in urogenital tissues. Through overexpression experiments in transgenic mice, we further demonstrate the capability of SALL1 to induce the ectopic gene expression programs that are a signature of mole ovotestes. Our results highlight the co-option of gene expression, through changes in enhancer activity, as a prominent mechanism for the evolution of traits. We used ChIP-seq for three histone modifications, H3K4me1, H3K4me3 and H3K27ac to identify regulatory elements in developing gonads Overall design: We performed enhancer identification analyses using the software CRUP and combining the three histone marks