title: Hormonal regulation and characterisation of the mouse Cyp4b1 gene 5'-flanking region.
abstract: The Cyp4b1 structural gene comprises 12 exons that span approximately 23kb. The transcriptional initiation site, mapped by 5(')-RACE and primer extension analyses from kidney mRNA, was found to be 34-bp upstream of the translation initiation site. Cyp4b1 mRNA expression was found restricted to kidney and androgenic up-regulation in several mouse strains was observed. Spatial location investigated by in situ hybridisation revealed abundant and specific expression of Cyp4b1 mRNA in the proximal tubules of the renal cortex. A 1.8-kb murine Cyp4b1 5(')-flanking region, which encompasses a TATA box-like sequence and several putative transcription factor-binding sites, was isolated. Transient transfection studies with different Cyp4b1 promoter constructs indicated that this flanking region exhibits promoter activity when expressed in different cell lines and that a 98-truncated fragment represents the minimal sequence required for basal transcription. Androgen responsiveness was examined by cotransfection with an androgen receptor expression vector, in the presence of androgens.
authors.affiliation: Centre d'Investigacions en Bioqui;mica i Biologia Molecular, Hospital Universitari Vall d'Hebron, Pg. Vall d'Hebron 119-129, Barcelona 08035, Spain.
authors.forename: Joan
authors.initials: J
authors.lastname: Isern
authors.forename: Anna
authors.initials: A
authors.lastname: Meseguer
mesh_terms: D024506:5' Flanking Region; D000595:Amino Acid Sequence; D000818:Animals; D001189:Aryl Hydrocarbon Hydroxylases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D002460:Cell Line; D013196:Dihydrotestosterone / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D017930:Genes, Reporter; D017403:In Situ Hybridization; D007668:Kidney / Q000166:cytology / Q000502:physiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011944:Receptors, Androgen / Q000378:metabolism; D014018:Tissue Distribution; D024363:Transcription Initiation Site
chemical_list: D012333:RNA, Messenger; D011944:Receptors, Androgen; D013196:Dihydrotestosterone; D001189:Aryl Hydrocarbon Hydroxylases; C095029:cytochrome P-450 CYP4B1