Open AccessRapid regulation of c-myc protooncogene expression by progesterone in the avian oviduct.
Author(s) -
Karen Fink,
Eric D. Wieben,
Gayle E. Woloschak,
Thomas C. Spelsberg
Publication year - 1988
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.85.6.1796
Subject(s) - oviduct , messenger rna , biology , medicine , endocrinology , steroid , gene expression , receptor , rna , transcription (linguistics) , gene , steroid hormone , progesterone receptor , microbiology and biotechnology , hormone , biochemistry , genetics , linguistics , philosophy , cancer , estrogen receptor , breast cancer
The mRNA levels of genes known to be regulated by sex steroids are not altered until 1 hr or longer after steroid treatment, although the steroid receptor complexes are bound to nuclear acceptor sites within 5 min. In a search for early regulation of gene transcription, total chick oviduct RNA was isolated at various times after injection (i.p.) of progesterone and analyzed for c-myc expression. Levels of c-myc mRNA began to decrease in response to progesterone by 10 min after injection. The mRNA levels continued to decrease, reached a 70% reduction at 30 min, and returned to control values by 8 hr after steroid injection. Changes in alpha-tubulin mRNA levels were markedly less in these same RNA preparations. The effect was dependent on the dose of the steroid and was target-tissue specific. These changes occurred much more rapidly than changes in egg-white protein mRNA levels. Vehicle alone did not alter c-myc mRNA levels. Early regulated genes such as c-myc may represent the initial site of action of steroid receptors in the genome.