Molecular and biochemical characterization of two P450 enzymes in the ecdysteroidogenic pathway of Drosophila melanogaster.

ABSTRACT: Five different enzymatic activities, catalyzed by both microsomal and mitochondrial cytochrome P450 monooxygenases (CYPs), are strongly implicated in the biosynthesis of ecdysone (E) from cholesterol. However, none of these enzymes have been characterized completely. The present data show that the wild-type genes of two members of the Halloween family of embryonic lethals, disembodied (dib) and shadow (sad), code for mitochondrial cytochromes P450 that mediate the last two hydroxylation reactions in the ecdysteroidogenic pathway in Drosophila, namely the C22- and C2-hydroxylases. When sad (CYP315A1) is transfected into Drosophila S2 cells, the cells metabolize 2-deoxyecdysone (2dE) to E and the [3H]ketotriol (2,22-dideoxyecdysone) to 22-deoxyecdysone. In contrast, dib (CYP302A1) is respons

SUBMITTER: Warren JT 

PROVIDER: S-EPMC123207 | biostudies-literature | 2002 Aug

REPOSITORIES: biostudies-literature