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Expression Analysis of Mammalian Linker-histone Subtypes
Published on: March 19, 2012
Human HMG box transcription factor HBP1: a role in hCD2 LCR function
T Zhuma1, R Tyrrell, B Sekkali
1Division of Molecular Immunology, National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK.
The EMBO Journal
|November 24, 1999
Summary
The HMG box containing protein-1 (HBP1) binds to the human CD2 gene locus control region (LCR). This binding is crucial for preventing position effect variegation (PEV) and ensuring proper gene expression in transgenic mice.
Area of Science:
- Genetics
- Molecular Biology
- Epigenetics
Background:
- The human CD2 gene locus control region (LCR) regulates T cell-specific gene expression.
- The LCR contains an enhancer and HSS3, which prevents position effect variegation (PEV).
Purpose of the Study:
- Identify factors binding to the HSS3 element of the hCD2 LCR.
- Investigate the role of these factors in gene expression and PEV prevention.
Main Methods:
- Electrophoretic mobility shift assays (EMSAs) to identify DNA-binding proteins.
- Generation and analysis of transgenic mice with modified hCD2 LCR constructs.
Main Results:
- HMG box containing protein-1 (HBP1) was identified as a factor binding to HSS3.
- HBP1 binds to a high-affinity TTCATTCATTCA sequence within the LCR.
- Deletion of HBP1-binding sites in transgenic mice leads to PEV when integrated in heterochromatic regions.
Conclusions:
- HBP1 plays a critical role in preventing PEV by facilitating chromatin opening and remodeling.
- HBP1 binding to the hCD2 LCR is essential for stable, position-independent gene expression.
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