CELL-SPECIFIC NUCLEAR RECEPTOR REGULATES THE STEROID HYDROXYLASES

Recent studies of the gene regulation of the cytochrome P450 steroid h ydroxylases have established a key role for an orphan nuclear receptor , designated steroidogenic factor I (SF-I). SF-I binds to shared promo ter elements upstream of the steroid hydroxylases to mediate their coo rdinate expression in steroidogenic cells. Analyses of SF-1 expression during mouse embryonic development showed that SF-1 is expressed from the earliest stages of organogenesis of the steroidogenic tissues, su ggesting an intimate link between SF-1 and steroidogenic cell differen tiation. Finally, in gene disruption experiments, the gene encoding SF -I was shown to be essential for development of the adrenal glands and gonads. These results establish the essential role of this orphan nuc lear receptor in the development and function of the primary steroidog enic tissues.