Involved in the metabolism of insect hormones; responsible for ecdysteroid C25-hydroxylase activity. May be involved in the breakdown of synthetic insecticides. Steroid biosynthesis; ecdysteroid biosynthesis. First seen at the early (syncytial) blastoderm stage 4. During cellularization of the blastoderm (stage 5), stripes of expression appear and remain through to stage 10. Expression becomes undetectable during germ band retraction (stages 11-14). By stage 15, some expression resumes in the primordium of the ring gland, so that by stage 17 strong expression is seen, but only in the ring gland. This specific localization continues throughout the larval instars (at protein level). Expressed in the prothoracic gland cells of the larval ring gland (RG). Levels decline just after the molt to the third instar then increase later during the wandering stage. Low levels of expression are seen in the larval brain and fat body. In the adult, majority of expression is restricted to the ovaries, with low levels in the head and carcass of both sexes. Expressed both maternally and zygotically. Member of the Halloween gene group. Belongs to the cytochrome P450 family. It is uncertain whether Met-1 or Met-14 is the initiator.