Characterization, expression and transcriptional regulation of P450c17-I and -II in the medaka, Oryzias latipes.
Recently we reported the isolation of two types of cytochrome P450c17s (steroid 17alpha-hydroxylase/C17, 20 lyase) encoded by two different genes, from genomes of teleost fish. In this study, we characterized the expression profile, enzymatic activity and transcriptional regulation of P450c17-I and -II in the medaka ovary. Similar to tilapia, medaka P450c17-I possessed both hydroxylase and lyase activities, while P450c17-II possessed only the hydroxylase activity. In situ hybridization and gene expression profiles during 48h prior to spawning indicated that P450c17-I is responsible for the production of estradiol-17beta during oocyte growth, while P450c17-II for the production of 17alpha, 20beta-dihydroxy-4-pregnen-3-one during oocyte maturation and cortisol production in the head kidney. Luciferase assays and expression profiles of transcription factors as revealed by real time PCR suggested that P450c17-I and -II expression are tightly controlled by Ad4BP/SF-1, Lrh-1, Foxl2, and Dax1 during the 48 h prior to spawning.
Zhou
Lin-Yan
LY
Laboratory of Reproductive Biology, National Institute for Basic Biology, Okazaki 444-8585, Japan.
Wang
De-Shou
DS
Shibata
Yasushi
Y
Paul-Prasanth
Bindhu
B
Suzuki
Aya
A
Nagahama
Yoshitaka
Y
D000818:Animals; D002855:Chromatography, Thin Layer / Q000379:methods; D003001:Cloning, Molecular; D005786:Gene Expression Regulation; D006854:Hydrocortisone / Q000378:metabolism; D017403:In Situ Hybridization; D007668:Kidney / Q000378:metabolism; D006899:Mixed Function Oxygenases / Q000378:metabolism; D009990:Oryzias / Q000235:genetics*; D011401:Promoter Regions, Genetic; D013254:Steroid 17-alpha-Hydroxylase / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics*; D013997:Time Factors; D014158:Transcription, Genetic
D006899:Mixed Function Oxygenases; D013254:Steroid 17-alpha-Hydroxylase; D006854:Hydrocortisone