title: Regional expression of androgen receptor coregulators and androgen action in the mouse epididymis.
abstract: Endocrine regulation of the mouse initial segment (IS) and distal caput  epididymides was studied using genome-wide profiling of gene expression. Among  the IS-enriched genes, 29% were significantly down-regulated 1 day after  gonadectomy. Of those genes, dihydrotestosterone (DHT) supplementation was not  sufficient to maintain their pregonadectomy level of expression in 70%. Of the  caput-enriched genes, 16% were significantly down-regulated after gonadectomy,  and of those genes, DHT supplementation did not maintain the initial level of  expression in 28%. Identical data were obtained by clustering analyses  performed for the expression data of epididymal genes. Furthermore, the  microarray data revealed that 26 androgen receptor coregulators were expressed  in the epididymis, of which several were confirmed by quantitative reverse  transcriptase polymerase chain reaction analysis. This suggests putative  involvement of these proteins in the segment-specific regulation of the  epididymal genes. The pattern of epididymal gene expression in the novel  proximal epididymis-specific androgen receptor knockout mouse ProxE-ARKO, with  severe hypotrophy and hypoplasia of the caput epithelium, furthermore  suggested that a subset of genes whose expression cannot be maintained by  systemic androgen alone still require either direct lumicrine androgen action  or a permissive effect of circulating testosterone. It is evident that  testicular factors, one of which could be the high-concentration luminal  androgen, are important for the expression of IS-enriched genes, whereas the  expression of distal caput-enriched genes is typically regulated by systemic  androgens.
authors.affiliation: Department of Physiology, Institute of Biomedicine, University of Turku, Turku, Finland. petra.sipila@utu.fi
authors.forename: Petra
authors.initials: P
authors.lastname: Sipilä
authors.forename: Anton
authors.initials: A
authors.lastname: Krutskikh
authors.forename: Dwi Ari
authors.initials: DA
authors.lastname: Pujianto
authors.forename: Matti
authors.initials: M
authors.lastname: Poutanen
authors.forename: Ilpo
authors.initials: I
authors.lastname: Huhtaniemi
mesh_terms: D000818:Animals; D013196:Dihydrotestosterone / Q000378:metabolism* / Q000494:pharmacology; D004822:Epididymis / Q000187:drug effects / Q000378:metabolism*; D020869:Gene Expression Profiling; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D009919:Orchiectomy; D011944:Receptors, Androgen / Q000378:metabolism*; D013739:Testosterone / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D011944:Receptors, Androgen; D013196:Dihydrotestosterone; D013739:Testosterone