Our work on the hormonal regulation of the human thyrotropin-releasing hormone (TRH) gene has identified a novel thyroid hormone response element through which thyroid hormone inhibits TRH production at the transcriptional level. In the following proposal we will use the molecular techniques gained during my training to fully characterize this negative regulatory element and define its interactions with thyroid hormone receptor (TR) isoforms and TR accessory proteins (TRAPs), such as the retinoid X receptor (RXR). These studies should provide new information on the basic mechanism in which the TR negatively regulates gene expression. The TRH gene also provides an ideal model to explore the syndromes of resistance to thyroid hormone. We hypothesize that dominant negative inhibition by mutant TRs on negative TRES is fundamentally different than on positive TRES, which allows specific mutant TRs to cause resistance only in the hypothalamus and the pituitary while having normal function in the periphery. To extend our work to the TRH neuron itself, we will utilize transgenic technology in collaboration with the Beth Israel Transgenic Facility, to produce a TRH producing neuronal cell line. The development of such a line will have future impact on the regulation of TRH gene expression and our understanding of hypothalamic development.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Clinical Investigator Award (CIA) (K08)
Project #
5K08DK002354-05
Application #
2900073
Study Section
Diabetes, Endocrinology and Metabolic Diseases B Subcommittee (DDK)
Program Officer
Hyde, James F
Project Start
1995-04-28
Project End
2000-03-31
Budget Start
1999-04-01
Budget End
2000-03-31
Support Year
5
Fiscal Year
1999
Total Cost
Indirect Cost
Name
Beth Israel Deaconess Medical Center
Department
Type
DUNS #
076593722
City
Boston
State
MA
Country
United States
Zip Code
02215
Cohen, R N; Wondisford, F E; Hollenberg, A N (1998) Two separate NCoR (nuclear receptor corepressor) interaction domains mediate corepressor action on thyroid hormone response elements. Mol Endocrinol 12:1567-81
Monden, T; Wondisford, F E; Hollenberg, A N (1997) Isolation and characterization of a novel ligand-dependent thyroid hormone receptor-coactivating protein. J Biol Chem 272:29834-41
Langlois, M F; Zanger, K; Monden, T et al. (1997) A unique role of the beta-2 thyroid hormone receptor isoform in negative regulation by thyroid hormone. Mapping of a novel amino-terminal domain important for ligand-independent activation. J Biol Chem 272:24927-33
Werman, A; Hollenberg, A; Solanes, G et al. (1997) Ligand-independent activation domain in the N terminus of peroxisome proliferator-activated receptor gamma (PPARgamma). Differential activity of PPARgamma1 and -2 isoforms and influence of insulin. J Biol Chem 272:20230-5
Hollenberg, A N; Susulic, V S; Madura, J P et al. (1997) Functional antagonism between CCAAT/Enhancer binding protein-alpha and peroxisome proliferator-activated receptor-gamma on the leptin promoter. J Biol Chem 272:5283-90
Safer, J D; Langlois, M F; Cohen, R et al. (1997) Isoform variable action among thyroid hormone receptor mutants provides insight into pituitary resistance to thyroid hormone. Mol Endocrinol 11:16-26
Hollenberg, A N; Monden, T; Madura, J P et al. (1996) Function of nuclear co-repressor protein on thyroid hormone response elements is regulated by the receptor A/B domain. J Biol Chem 271:28516-20