title: Liver receptor homologue-1 (LRH-1) activates the promoter of brain aromatase (cyp19a2) in a teleost fish, the medaka, Oryzias latipes.
abstract: The medaka, Oryzias latipes, like other fish, have two distinct aromatase genes, the ovarian (cyp19a1) and brain (cyp19a2) forms. We previously reported that Ad4BP/SF-1, a member of the NR5A subfamily, plays an important role in the regulation of cyp19a1 expression in medaka ovarian follicles during vitellogenesis. In the present study, we investigated whether liver receptor homologue-1 (LRH-1), another NR5A subfamily member, is involved in the regulation of cyp19a2 expression in the medaka brain. In situ hybridization analysis revealed that LRH-1 was expressed in the hypothalamus, where it colocalized with aromatase (cyp19a2). We then showed by transient transfection assays that LRH-1 was able to increase expression of a cyp19a2 reporter gene in various mammalian cell lines, and that mutation of a putative LRH-1 binding site within the cyp19a2 promoter abolished this effect. Taken together, these findings suggest that LRH-1 plays a role in regulating cyp19a2 expression in the medaka brain. This is the first to demonstrate in vitro the activation of brain aromatase by LRH-1 in the vertebrate brain.
authors: Department of Basic Biology, The Graduate University for Advanced Studies, Okazaki, Japan.
authors: Yuki
authors: Y
authors: Ohmuro-Matsuyama
authors: Kataaki
authors: K
authors: Okubo
authors: Masaru
authors: M
authors: Matsuda
authors: Shigeho
authors: S
authors: Ijiri
authors: Deshou
authors: D
authors: Wang
authors: Guijun
authors: G
authors: Guan
authors: Taiga
authors: T
authors: Suzuki
authors: Makoto
authors: M
authors: Matsuyama
authors: Ken-Ichiro
authors: K
authors: Morohashi
authors: Yoshitaka
authors: Y
authors: Nagahama
mesh_terms: D000818:Animals; D001141:Aromatase / Q000032:analysis / Q000235:genetics*; D001483:Base Sequence; D001921:Brain / Q000201:enzymology*; D002460:Cell Line; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D008969:Molecular Sequence Data; D009990:Oryzias / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear / Q000032:analysis / Q000235:genetics / Q000502:physiology*; D015534:Trans-Activators / Q000032:analysis / Q000235:genetics / Q000502:physiology*; D024363:Transcription Initiation Site
chemical_list: D012333:RNA, Messenger; D018160:Receptors, Cytoplasmic and Nuclear; D015534:Trans-Activators; D001141:Aromatase