Understanding the mechanisms of regulation of gene expression is essential to a comprehension of development and differentiation, and thus, cancer and other disorders that may arise when these processes go awry. Glucocorticoids and progestins regulate numerous processes in normal physiology and disease including pregnancy, lung and breast development, stress response, inflammation, and cancer. The receptors for these steroid hormones control these processes by regulation transcription of target genes. Our long term goal is to understand the molecular details of these regulatory mechanisms. Such knowledge could drive the improvement of existing therapeutic regimens and the development of novel avenues for intervention, particularly in endocrine-dependent neoplasia and inflammatory disease. This application addresses two very broad and fundamental issues in the regulation of gene expression. The first is the role of chromatin in gene expression and the second is how two transcription factors that have little ability to distinguish individual DNA target sites can mediate very different biological actions. The focus of the first aim is to apply new strategies we have developed or brought to the lab to maintain the recycling of glucocorticoid receptor activity in the context of an in vitro transcription system. A key feature of this system is that it employs chromatin templates in order to understand mechanisms of receptor action in a more biologically relevant context.
The second aim builds on the first to examine the role of individual coregulatory proteins in glucocorticoid receptor action in vitro. The role of chromatin remodeling and modification will be a special focus. The third and fourth aims are directed toward understanding mechanisms of differential gene regulation by glucocorticoid and progesterone receptors. We will exploit differentially expressed genes we have recently identified in aim three for mechanistic studies.
In aim four we will expand on our novel finding that the chromatin environment surrounding a promoter can influence gene regulation by receptors in both a qualitative and quantitative fashion by identifying additional examples and analyzing the chromosomal sites to understand the basis of this regulation. Together these studies will make significant contributions to our understanding of hormone action.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK037061-17
Application #
6721261
Study Section
Endocrinology Study Section (END)
Program Officer
Margolis, Ronald N
Project Start
1986-07-01
Project End
2006-03-31
Budget Start
2004-04-01
Budget End
2006-03-31
Support Year
17
Fiscal Year
2004
Total Cost
$231,394
Indirect Cost
Name
University of Colorado Denver
Department
Pathology
Type
Schools of Medicine
DUNS #
041096314
City
Aurora
State
CO
Country
United States
Zip Code
80045
Wang, Stanley Y; Ahn, Bonnie S; Harris, Rebecca et al. (2004) Fluorescence anisotropy microplate assay for analysis of steroid receptor-DNA interactions. Biotechniques 37:807-8, 810-7
Wan, Yihong; Nordeen, Steven K (2003) Overlapping but distinct profiles of gene expression elicited by glucocorticoids and progestins. Recent Prog Horm Res 58:199-226
Lambert, James R; Nordeen, Steven K (2003) CBP recruitment and histone acetylation in differential gene induction by glucocorticoids and progestins. Mol Endocrinol 17:1085-94
Wan, Yihong; Nordeen, Steven K (2002) Overlapping but distinct gene regulation profiles by glucocorticoids and progestins in human breast cancer cells. Mol Endocrinol 16:1204-14
Wan, Y; Nordeen, S K (2002) Identification of genes differentially regulated by glucocorticoids and progestins using a Cre/loxP-mediated retroviral promoter-trapping strategy. J Mol Endocrinol 28:177-92
Thackray, Varykina G; Nordeen, Steven K (2002) High-yield purification of functional, full-length steroid receptor coactivator 1 expressed in insect cells. Biotechniques 32:260, 262-3
Wan, Y; Coxe, K K; Thackray, V G et al. (2001) Separable features of the ligand-binding domain determine the differential subcellular localization and ligand-binding specificity of glucocorticoid receptor and progesterone receptor. Mol Endocrinol 15:17-31
Jiang, W; Nordeen, S K; Kadonaga, J T (2000) Transcriptional analysis of chromatin assembled with purified ACF and dNAP1 reveals that acetyl-CoA is required for preinitiation complex assembly. J Biol Chem 275:39819-22
Day, R N; Nordeen, S K; Wan, Y (1999) Visualizing protein-protein interactions in the nucleus of the living cell. Mol Endocrinol 13:517-26
Grimm, S L; Nordeen, S K (1999) Luciferase reporter gene vectors that lack potential AP-1 sites. Biotechniques 27:220-2

Showing the most recent 10 out of 32 publications