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Low pH enhances Sp1 DNA binding activity and interaction with TBP
Takayuki Torigoe1, Hiroto Izumi, Yoichiro Yoshida
1Department of Molecular Biology, University of Occupational and Environmental Health, School of Medicine, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan.
Nucleic Acids Research
|July 31, 2003
Summary
The transcription factor Sp1 (Specificity Protein 1) enhances DNA binding and TBP interaction at low pH. This pH-dependent activity is crucial for cellular responses in acidic environments, like tumors.
Area of Science:
- Molecular Biology
- Cellular Physiology
- Biochemistry
Background:
- Specificity Protein 1 (Sp1) regulates diverse genes, including those in tumor growth.
- Sp1, a C2-H2 zinc-finger protein, protects cells in hypoxic or acidic conditions.
- Tumor cells often experience acidic microenvironments.
Purpose of the Study:
- To investigate the molecular mechanisms of pH-dependent transcription by Sp1.
- To understand how pH affects Sp1's DNA binding and interaction with TATA-binding protein (TBP).
Main Methods:
- Investigated Sp1's DNA binding activity across various pH conditions.
- Examined Sp1's interaction with TBP under different pH levels.
Main Results:
- Sp1's DNA binding activity significantly increased at low pH.
- A stable interaction between Sp1 and TBP was observed at low pH.
- pH was shown to modulate Sp1 activity.
Conclusions:
- Low pH enhances Sp1's DNA binding and its interaction with TBP.
- pH-dependent modulation of Sp1 activity contributes to cellular adaptation in acidic conditions.
- Findings provide insight into Sp1 function in tumor microenvironments.
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