title: Hormonal regulation and expression of the jun-D protooncogene in specific cell types of the rat uterus.
abstract: Steroid hormone regulation and cell-type specific expression of the jun-D protooncogene in rat uterus was examined. Adult, ovariectomized rats were injected with progesterone, testosterone, 17beta-estradiol (E2-17beta), 16alpha-estradiol (E2-16alpha), dexamethasone or cycloheximide. Uteri were collected between 0 and 6 h post-treatment. Northern blot analysis of uterine RNA revealed that induction of jun-D was specific for estrogenic steroids, as progesterone and testosterone had no effect on expression of this member of the jun gene family. Treatment with E2-17beta increased jun-D mRNA levels by approx. 5-fold, with expression reaching peak levels at 3 h after treatment and declining thereafter. Administration of E2-16alpha, a short-acting estrogen that does not cause uterine cell proliferation, increased expression of jun-D but with different kinetics compared to the long-acting E2-17beta. The mRNA levels of jun-D increased by 3-fold 1 h after administration of E2-16alpha but declined soon after. Slight induction of jun-D mRNA by dexamethasone was apparent, but to a much lesser extent compared to estrogen. The protein synthesis inhibitor, cycloheximide, did not block jun-D induction, indicating that this is an "immediate early" response. Expression of Jun-D protein was examined by immunohistochemical methods. E2-17beta treatment activated jun-D primarily in the nuclei of luminal and glandular epithelial cells of the endometrium. These results demonstrate that hormonal induction of jun-D is specific for estrogens and that uterine expression of this protooncogene occurs in a cell-type specific manner.
authors.affiliation: Department of Anatomy, University of Cincinnati College of Medicine, OH 45267-0521, USA.
authors.forename: K P
authors.initials: KP
authors.lastname: Nephew
authors.forename: D K
authors.initials: DK
authors.lastname: Webb
authors.forename: K C
authors.initials: KC
authors.lastname: Akcali
authors.forename: B C
authors.initials: BC
authors.lastname: Moulton
authors.forename: S A
authors.initials: SA
authors.lastname: Khan
mesh_terms: D000818:Animals; D003907:Dexamethasone / Q000494:pharmacology; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D005786:Gene Expression Regulation / Q000235:genetics; D016758:Genes, jun / Q000235:genetics*; D007150:Immunohistochemistry; D010052:Ovariectomy; D011374:Progesterone / Q000031:analogs & derivatives / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013256:Steroids / Q000494:pharmacology*; D014599:Uterus / Q000166:cytology*
chemical_list: D012333:RNA, Messenger; D013256:Steroids; D011374:Progesterone; D004958:Estradiol; D003907:Dexamethasone