Organization and expression of genes encoding prostatic steroid binding protein.
We have cloned the genes for prostatic steroid binding protein to study the mechanism whereby their expression is regulated by testosterone. The genes for the C1 and C2 polypeptides are probably unique whereas there are two genes C3(1) and C3(2) for the C3 polypeptide of which only the former is transcribed in vivo. The state of DNA methylation associated with the two genes for C3 also differ, insofar as C3(1) is demethylated in ventral prostate from 14-28 days of age, whereas the C3(2) gene remains hypermethylated. The organization of all four genes is similar and appreciable DNA sequence homologies suggest that they may have arisen from a single ancestral gene. To study C3 expression and its hormonal regulation we have introduced the cloned genes into mouse S115 cells, an androgen-responsive cell line. Both genes were accurately transcribed and their expression was stimulated up to fivefold by 10(-8) M testosterone in approximately one third of the clones tested. To delineate the site of action of the hormone we have constructed chimeric genes consisting of putative C3 promoters and regulatory sequences together with a marker gene, interferon. This chimeric gene resulted in interferon production but its expression was stimulated by less than twofold in all clones tested. Therefore, these results indicate that, in mouse cells, testosterone does not interact directly with the rat C3 promoter but, in certain clones, may act post-transcriptionally.
D000727:Androgen-Binding Protein / Q000235:genetics*; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics*; D002478:Cells, Cultured; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects; D008297:Male; D051379:Mice; D009876:Operon; D011467:Prostate / Q000378:metabolism*; D060789:Prostatein; D051381:Rats; D060765:Secretoglobins; D013739:Testosterone / Q000494:pharmacology; D014598:Uteroglobin; D060788:Mammaglobin B
D000727:Androgen-Binding Protein; D002352:Carrier Proteins; D004247:DNA; D060789:Prostatein; D060765:Secretoglobins; D013739:Testosterone; D014598:Uteroglobin; C511484:Scgb1d2 protein, rat; C511483:Scgb1d4 protein, rat; C556468:Scgb2a1 protein, rat; D060788:Mammaglobin B