title: Human leukotriene B4 omega-hydroxylase (CYP4F3) gene: molecular cloning and chromosomal localization.
abstract: Leukotriene B4 (LTB4) omega-hydroxylase catalyzes the conversion of LTB4 into a biologically less active product, 20-hydroxy-LTB4. In a preceding paper (Kikuta et al., 1993), we showed human polymorphonuclear leukocyte (PMN) LTB4 omega-hydroxylase to be a novel form of cytochrome P450, designated CYP4F3, on the basis of its cDNA cloning and expression in yeast cells. Here, we have isolated the gene encoding CYP4F3 and determined its genomic organization and chromosomal localization. The CYP4F3 gene contained 13 exons and spanned approximately 22.2 kb. The cDNA of CYP4F3 contained 5050 nucleotides excluding the poly(A) tail. The translation initiation codon (ATG) was present in exon II. Primer extension and S1 mapping analyses indicated that the transcription initiation site is 49 nucleotides upstream from the 3' end of exon I, and no other initiation sites were detected. A TATA-box-like sequence (TACAT) and 120-b GC-rich sequence were observed just before transcription initiation site. Several putative regulating elements recognized by the GATA family, MZF-1, CACCC binding protein, and C/EBP, were identified in its 5' flanking region. Genomic DNA screening for CYP4F3 and Southern blot analysis suggested the existence of other CYP4F genes in addition to CYP4F3 and CYP4F2 in the human genome. Fluorescence in situ hybridization demonstrated that the CYP4F3 gene is located at 19p13.2.
authors.affiliation: Department of Food Science and Technology, Faculty of Engineering, Fukuyama University, Hiroshima, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kikuta
authors.forename: M
authors.initials: M
authors.lastname: Kato
authors.forename: Y
authors.initials: Y
authors.lastname: Yamashita
authors.forename: Y
authors.initials: Y
authors.lastname: Miyauchi
authors.forename: K
authors.initials: K
authors.lastname: Tanaka
authors.forename: N
authors.initials: N
authors.lastname: Kamada
authors.forename: M
authors.initials: M
authors.lastname: Kusunose
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D015139:Blotting, Southern; D002874:Chromosome Mapping; D002888:Chromosomes, Human, Pair 19; D003001:Cloning, Molecular; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D000072470:Cytochrome P450 Family 4; D006801:Humans; D017403:In Situ Hybridization / Q000379:methods; D006899:Mixed Function Oxygenases / Q000235:genetics*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger; D014158:Transcription, Genetic
chemical_list: D012333:RNA, Messenger; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D000072470:Cytochrome P450 Family 4; C040780:leukotriene B4 20-hydroxylase