title: Cytochrome P450 CYP307A1/Spook: a regulator for ecdysone synthesis in insects.
abstract: The prothoracic gland (PG) has essential roles in synthesizing and secreting a steroid hormone called ecdysone that is critical for molting and metamorphosis of insects. However, little is known about the genes controlling ecdysteroidogenesis in the PG. To identify genes functioning in the PG of the silkworm, Bombyx mori, we used differential display PCR and focused on a cytochrome P450 gene designated Cyp307a1. Its expression level positively correlates with a change in the hemolymph ecdysteroid titer. In addition, Drosophila Cyp307a1 is encoded in the spook locus, one of the Halloween mutant family members showing a low ecdysone titer in vivo, suggesting that Cyp307a1 is involved in ecdysone synthesis. While Drosophila Cyp307a1 is expressed in the early embryos and adult ovaries, the expression is not observed in the PGs of embryos or third instar larvae. These results suggest a difference in the ecdysone synthesis pathways during larval development in these insects.
authors.affiliation: Department of Integrated Biosciences, Rm. 201, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan.
authors.forename: Toshiki
authors.initials: T
authors.lastname: Namiki
authors.forename: Ryusuke
authors.initials: R
authors.lastname: Niwa
authors.forename: Takashi
authors.initials: T
authors.lastname: Sakudoh
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Shirai
authors.forename: Hideaki
authors.initials: H
authors.lastname: Takeuchi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kataoka
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D012831:Bombyx / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D003577:Cytochrome P-450 Enzyme System / Q000145:classification / Q000235:genetics* / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics; D004440:Ecdysone / Q000096:biosynthesis*; D020869:Gene Expression Profiling; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D010802:Phylogeny; D012333:RNA, Messenger / Q000032:analysis; D016415:Sequence Alignment
chemical_list: D029721:Drosophila Proteins; D012333:RNA, Messenger; D004440:Ecdysone; D003577:Cytochrome P-450 Enzyme System