title: The human type II 17 beta-hydroxysteroid dehydrogenase gene encodes two alternatively spliced mRNA species.
abstract: The isozymes of the 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) gene family are responsible for the formation of the 17 beta-hydroxysteroids delta 5-androstene-3 beta,17 beta-diol, testosterone, 17 beta-estradiol, and dihydrotestosterone from their corresponding 17-ketosteroid precursors, thus playing a pivotal role in the formation of active sex steroids in both steroidogenic and peripheral target tissues. To clone the type II 17 beta-HSD gene, the full-length cDNA type II 17 beta-HSD was used as probe to screen a human leukocyte genomic DNA library. The type II 17 beta-HSD gene contains seven exons and spans > 40 kbp. The type II 17 beta-HSD gene encodes two alternatively spliced mRNAs that give rise to the previously identified type IIA 17 beta-HSD protein of 387 amino acids, as well as to a related 291-amino-acid type IIB 17 beta-HSD protein of unknown function. RNA blot analysis revealed the presence of a major 1.45-kb transcript that is abundant in placenta and endometrium. The mRNA cap site has been localized in a region between 179 and 167 nucleotides upstream of the ATG start codon by RNase protection and S1 nuclease mapping analyses. Cloning of the 17 beta-HSD type II gene provides us with the tools to study its transcriptional expression.
authors.affiliation: CHUL Research Center, Québec, Canada.
authors.forename: Y
authors.initials: Y
authors.lastname: Labrie
authors.forename: F
authors.initials: F
authors.lastname: Durocher
authors.forename: Y
authors.initials: Y
authors.lastname: Lachance
authors.forename: C
authors.initials: C
authors.lastname: Turgeon
authors.forename: J
authors.initials: J
authors.lastname: Simard
authors.forename: C
authors.initials: C
authors.lastname: Labrie
authors.forename: F
authors.initials: F
authors.lastname: Labrie
mesh_terms: D015067:17-Hydroxysteroid Dehydrogenases / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D004717:Endometrium / Q000201:enzymology; D005091:Exons; D005260:Female; D015723:Gene Library; D005796:Genes; D005822:Genetic Vectors; D012739:Gonadal Steroid Hormones / Q000096:biosynthesis; D006801:Humans; D007527:Isoenzymes / Q000235:genetics*; D008969:Molecular Sequence Data; D010920:Placenta / Q000201:enzymology; D012326:RNA Splicing; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D012739:Gonadal Steroid Hormones; D007527:Isoenzymes; D012333:RNA, Messenger; D015067:17-Hydroxysteroid Dehydrogenases