Related Experiment Videos
Negative regulation of CD4 gene expression by a HES-1-c-Myb complex
R D Allen1, H K Kim, S D Sarafova
1Department of Microbiology, Columbia University, College of Physicians and Surgeons, New York, New York 10032, USA.
Molecular and Cellular Biology
|April 5, 2001
Summary
The c-Myb transcription factor regulates CD4 gene expression. It acts as both a positive and negative regulator, with HES-1 inducing its repressive function during T-cell development.
Area of Science:
- Immunology
- Molecular Biology
- Gene Regulation
Background:
- CD4 gene expression is critical during thymopoiesis and tightly regulated.
- A transcriptional silencer in the CD4 locus controls CD4 downregulation in specific T lymphocyte subsets.
Purpose of the Study:
- To identify factors binding to the CD4 silencer.
- To elucidate the role of c-Myb and HES-1 in CD4 gene regulation.
Main Methods:
- Analysis of transcription factor binding to the CD4 silencer.
- Investigation of protein-protein interactions between c-Myb and HES-1 in vivo.
Main Results:
- The transcription factor c-Myb binds to a functional site within the CD4 silencer.
- c-Myb is essential for both CD4 promoter function and silencer activity.
- HES-1 binds to c-Myb and converts it into a transcriptional repressor.
Conclusions:
- c-Myb plays dual roles in CD4 gene expression, acting as both an activator and repressor.
- The formation of a complex involving HES-1 and c-Myb at the silencer mediates CD4 gene repression during thymopoiesis.