Müllerian duct maintenance at the cranial region is promoted by Gata2

The paradigm of sexual differentiation holds that female embryos retain Müllerian ducts (the precursor of female reproductive tract organs) by default in the absence of anti-Müllerian hormone (AMH). Whether Müllerian duct maintenance requires active signaling has remained unclear. Here, we show that deletion of mesenchymal Gata2 induces selective regression of the cranial Müllerian duct (future oviduct). This regression did not result from ectopic AMH signaling but from loss of region-specific NRG1 signaling. In contrast, the caudal Müllerian duct (future uterus) was retained but displayed disrupted epithelial differentiation when Gata2 was deleted in either mesenchymal or epithelial compartments. Our findings reveal a region-specific, GATA2-dependent program that actively maintains the cranial Müllerian duct, reshaping our understanding of female reproductive tract development.