SRY signaling cascade

The war between FOXL2 (F) and SOX9/DMRT1 (M)
Early in the development of the embryo, the gonad has the potential to form either testis or ovary. Its fate hasn't yet been determined by "chromosomal sex." Two separate gene regulatory networks fight for control. The SOX9 gene regulatory network tries to shut down FOXL2 and cause the gonads to become the Leydig and Sertoli cells of the testes. The FOXL2 tries to shut down SOX9 and causes the gonads to become the follicular cells of the ovaries.

For the gonads to keep their programming as testes, the SOX9 protein has to keep getting itself produced. If this feed-forward loop is broken, SOX9 slowly dwindles as the proteins are degraded. Since FOXL2 tries to block this feed-forward loop by getting in the way of SOX9's promoter (named TESCO), SOX9 has to block the production of FOXL2 or it will lose its battle to make (and maintain) balls. To keep FOXL2 repressed, SOX9 stimulates the production of a henchman protein, DMRT1. DMRT1 blocks the production of FOXL2 by sitting on the region of DNA promoting its transcription. SOX9 makes more SOX9, and SOX9 makes DMRT1 which blocks FOXL2 which wants to block SOX9, keeping it dominant while keeping FOXL2, and the gonad's hopes and dreams of becoming a uterus, dormant.