The Transcriptional Regulator FOXR1 Is Required for Normal Early Embryogenesis but Dispensable for Male Fertility in Mice

FOXR1 belongs to the large conserved F-box family of DNA binding transcription factors that are involved in various developmental processes and diseases. The gene is important for embryogenesis in a fish model, brain development in mammals, and human FOXR1 was shown to possess oncogenic properties when it is abnormally expressed as a fusion gene. Earlier work on Foxr1 expression in mouse and human suggested roles for the protein in embryogenesis and sexual reproduction. We generated a mouse gene deletion model that revealed an embryonic lethal phenotype with partial penetrance and normal fertility in persistent homozygous male mutants. The results suggest that Foxr1 is functionally redundant in adult male gonads but needed for normal early embryo development and post-natal viability. We discuss our results in the context of publicly available human and rodent genomic and genetic data.