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Updated: Aug 8, 2026
13:20
Chromatin Immunoprecipitation (ChIP) to Assay Dynamic Histone Modification in Activated Gene Expression in Human Cells
Published on: July 29, 2010
Modification of Chromatin Structure by the Thyroid Hormone Receptor
1Laboratory of Molecular Embryology, National Institute of Child Health and Human Development, NIH, Bldg 18T, Rm 106, Bethesda, MD 20892-5431, USA.
Trends in Endocrinology and Metabolism: TEM
|May 14, 1999
Summary
Thyroid hormone receptors control gene transcription by recruiting histone deacetylases to silence genes and coactivators to activate them. This mechanism is crucial for normal gene control and is altered in cancer by mutated receptors.
Area of Science:
- Molecular Biology
- Genetics
- Endocrinology
Background:
- Thyroid hormone receptor (THR) plays a critical role in regulating gene expression.
- THR interacts with the chromosomal environment to control transcription.
- Understanding THR's mechanism is vital for gene regulation and disease research.
Purpose of the Study:
- To review how THR is assembled into chromatin.
- To elucidate the role of THR in transcriptional activation and repression.
- To discuss the implications for gene control and oncogenic transformation.
Main Methods:
- Review of pioneering experiments and recent observations.
- Analysis of THR's interaction with histone deacetylase (HDAC) and coactivators.
- Examination of conformational changes in THR upon hormone binding.
Main Results:
- In the absence of thyroid hormone, THR recruits HDAC to silence transcription.
- Upon hormone addition, THR releases HDAC and recruits coactivators (histone acetyltransferases).
- This dynamic recruitment regulates gene expression.
Conclusions:
- THR acts as a master regulator of the chromosomal environment.
- THR's mechanism is essential for normal gene control.
- Mutated THR, such as v-ErbA, can lead to oncogenic transformation through altered gene regulation.
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