title: A molecular genetic approach to the biosynthesis of the insect steroid molting hormone.
abstract: Insect growth, development, and molting depend upon a critical titer of the principal molting hormone of arthropods, 20-hydroxyecdysone (20E). Although the structure of 20E as a polyhydroxylated steroid was determined more than five decades ago, the exact steps in its biosynthesis have eluded identification. Over the past several years, the use of the fly database and the techniques and paradigms of biochemistry, analytical chemistry, and molecular genetics have allowed the cloning and sequencing of four genes in the Halloween gene family of Drosophila melanogaster, all of them encoding cytochrome P450 (CYP) enzymes, each of which mediates one of the four terminal hydroxylation steps in 20E biosynthesis. Further, the sequence of these hydroxylations has been determined, and developmental alterations in the expression of each of these genes have been quantified during both embryonic and postembryonic life.
authors.affiliation: Department of Biology, University of North Carolina, Chapel Hill North Carolina 27599, USA.
authors.forename: Lawrence I
authors.initials: LI
authors.lastname: Gilbert
authors.forename: James T
authors.initials: JT
authors.lastname: Warren
mesh_terms: D000818:Animals; D012831:Bombyx / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D029721:Drosophila Proteins / Q000378:metabolism; D004331:Drosophila melanogaster / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D004440:Ecdysone / Q000096:biosynthesis* / Q000235:genetics*; D026461:Ecdysteroids / Q000737:chemistry / Q000378:metabolism*; D015870:Gene Expression; D005786:Gene Expression Regulation; D017344:Genes, Insect / Q000235:genetics; D023281:Genomics / Q000379:methods; D006900:Hydroxylation; D019476:Insect Proteins / Q000737:chemistry / Q000235:genetics; D018402:Manduca / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D009154:Mutation
chemical_list: D029721:Drosophila Proteins; D026461:Ecdysteroids; D019476:Insect Proteins; D004440:Ecdysone; D003577:Cytochrome P-450 Enzyme System; C465627:sad protein, Drosophila; C416219:DIB protein, Drosophila