Post-transcriptional Regulation of Steroid Hormone Receptors
This review focuses on the post-transcriptional regulation of mRNAs that encode steroid hormone receptors, which exert powerful effects on physiology by regulating gene expression. Recent discoveries in the regulation of gene expression indicate that it i
- PDF / 403,490 Bytes
- 17 Pages / 439.37 x 666.14 pts Page_size
- 62 Downloads / 209 Views
Post-transcriptional Regulation of Steroid Hormone Receptors Nancy H. Ing
1
Introduction
Genome studies of diverse species indicate that mammalian physiology is unique not because of greater numbers of genes, but rather because of greater complexity of gene regulation (Mattick 2001; Maniatis and Reed 2002). Post-transcriptional regulation of gene expression (including mRNA stability and translation) is one of the ways that organisms control and modify the flow of genetic information into the proteome (Keene and Tenenbaum 2002). Within the continuum of gene expression from transcription to protein degradation, regulated mRNA stability is increasingly being recognized as a major effector of gene regulation. The first discoveries of steroid hormone effects on the stabilities of specific mRNAs were made in highly responsive animal tissues that were initiating largescale production of new proteins. Early studies determined that estrogen regulated stabilities of mRNAs in the livers of egg-laying animals at the initiation of oogenesis (McKnight and Palmiter 1979; Dodson and Shapiro 2002). In one example, estrogen stabilized the vitellogenin mRNA in frog liver by 40-fold, increasing the half-life of the mRNA from 16 to 600 h. While estrogen stabilized mRNAs encoding egg proteins, it also destabilized mRNAs encoding serum proteins in the frog liver. The rate of mRNA degradation has been established as equally important as the rate of synthesis in regulating the steady state concentration of the mRNA (Hargrove et al. 1991). The average mRNA half-life in mammalian cells is 24 h, with shortlived messages such as c-fos (FOS) mRNA having 20 min long half-lives and longlived RNAs, such as 28S and 18S rRNAs, having 4 day long half-lives (Hargrove and Schmidt 1989). The half-lives of mRNAs are important in determining how long each mRNA is present to act as a template for translation of proteins. N.H. Ing (*) Department of Animal Science, Texas A&M University, 2471 TAMU, College Station, TX 77843-2471, USA e-mail: [email protected] © Springer International Publishing Switzerland 2016 K.M.J. Menon, A.C. Goldstrohm (eds.), Post-transcriptional Mechanisms in Endocrine Regulation, DOI 10.1007/978-3-319-25124-0_5
91
92
N.H. Ing
In addition, the half-life of the mRNA also controls how rapidly its steady state concentrations can be altered. Expression of genes with short half-lived mRNAs are rapidly regulated by changes in transcription and degradation rates, while long-lived mRNAs may take days to achieve a new steady state level in response to a cell signal such as a steroid hormone. When comparing transcriptional and post-transcriptional up-regulation of gene expression, mRNA stabilization may be advantageous to organisms because it lacks the lag phase and energetic costs that occur for responses that increase the rates of gene transcription. Current reports elucidate post-transcriptional regulation that finely tunes the expression of steroid hormone receptor genes in animal tissues that are healthy or changing with the progres
Data Loading...
