Isolation and Characterization of Rat CYP11B Genes Involved in Late Steps of Mineralo- and Glucocorticoid Syntheses*

摘要: We isolated and characterized four forms of rat CYP11B genes, which were tentatively named CYP11B1, -B2, -B3, -B4. Genomic Southern analyses indicated that the members gene subfamily confined to these genes; among them, CYP11B1 -B2 encoded steroid 11 beta-hydroxylase aldosterone synthase, respectively, while CYP11B3 was a highly homologous without known expression product. By being devoid region spanning two exons conserved in other three, CYP11B4 presumably pseudogene. In nucleotide sequences, -B4 showed 95-96 93-100% identities coding 0.5-kilobase 5'-flanking regions, respectively. However, homology between sequences one three CYP11B2 rather low, about 90 50% As whole, than or more genes animals such as cow human. transient transfection experiments using mouse adrenocortical Y1 cells chloramphenicol acetyltransferase constructs, had 4- 10-fold higher promoter activity corresponding regions The possible presence suppressive element(s) noted upstream CYP11B1. Although variant cAMP-responsive element, present all animals, modified -B3 dibutyryl cAMP stimulated activities by 3-fold.