Nuclear hormone receptors and the Drosophila ecdysone response.

In Drosophila several members of the nuclear hormone receptor super-family are involved in regulating developmental pathways mediated by the steroid hormone ecdysone. At least seven genes encode a set of receptors which are expressed in a complex overlapping temporal and tissue-specific pattern. The variety of Drosophila receptors invites comparisons with mammalian systems and suggests that different receptors may interact to regulate developmental decisions. Once again the humble fruit fly is providing a genetic framework for understanding complex regulatory systems which have been conserved during evolution.