RRC ID 11316
著者 Maeda S, Nakashima A, Yamada R, Hara N, Fujimoto Y, Ito Y, Sonobe H.
タイトル Molecular cloning of ecdysone 20-hydroxylase and expression pattern of the enzyme during embryonic development of silkworm Bombyx mori.
ジャーナル Comp Biochem Physiol B Biochem Mol Biol
Abstract In various insects, 20-hydroxyecdysone (20E) is indispensable for embryonic development. In eggs of the silkworm Bombyx mori, 20E has been demonstrated to be produced by two metabolic pathways: de novo synthesis from cholesterol and dephosphorylation of ovary-derived physiologically inactive ecdysteroid phosphates. In the former, ecdysone 20-hydroxylase (E20OHase) has been suggested to be a key enzyme. In the latter, it has been demonstrated that the dephosphorylation of ecdysteroid phosphates is catalyzed by a specific enzyme, ecdysteroid-phosphate phosphatase (EPPase). In this study, a cDNA encoding E20OHase was cloned from 3-day-old nondiapause eggs of B. mori and sequenced using PCR techniques. The protein exhibited the signature sequences characteristic of P450 enzymes, and mediated the conversion of ecdysone to 20E using the baculovirus expression system. Semi-quantitative analysis revealed that the E20OHase mRNA is expressed predominantly during gastrulation and organogenesis in nondiapause eggs, but is scarcely detected in diapause eggs whose development is arrested at the late gastrula stage. The developmental changes in the expression patterns of E20OHase and EPPase suggest that both enzyme activities are regulated at the transcription level, and both enzymes contribute cooperatively to 20E formation during embryonic development.
巻・号 149(3)
ページ 507-16
公開日 2008-3-1
DOI 10.1016/j.cbpb.2007.11.015
PII S1096-4959(07)00444-7
PMID 18226571
MeSH Amino Acid Sequence Animals Aryl Hydrocarbon Hydroxylases / chemistry Aryl Hydrocarbon Hydroxylases / genetics* Baculoviridae Base Sequence Bombyx / embryology* Bombyx / enzymology* Chromatography, High Pressure Liquid Cloning, Molecular DNA, Complementary / genetics Embryonic Development* Gene Expression Regulation, Developmental Gene Expression Regulation, Enzymologic Magnetic Resonance Spectroscopy Molecular Sequence Data Phylogeny RNA, Messenger / genetics RNA, Messenger / metabolism Sequence Alignment Sequence Homology, Amino Acid Steroid Hydroxylases / chemistry Steroid Hydroxylases / genetics*
IF 2.219
引用数 18
WOS 分野 ZOOLOGY BIOCHEMISTRY & MOLECULAR BIOLOGY
リソース情報
カイコ NA