Hormonal regulation and expression of the jun-D protooncogene in specific cell types of the rat uterus.
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.
Nephew
K P
KP
Department of Anatomy, University of Cincinnati College of Medicine, OH 45267-0521, USA.
Webb
D K
DK
Akcali
K C
KC
Moulton
B C
BC
Khan
S A
SA
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*
D012333:RNA, Messenger; D013256:Steroids; D011374:Progesterone; D004958:Estradiol; D003907:Dexamethasone