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Published on: October 2, 2017
Structural insights into selective histone H3 recognition by the human Polybromo bromodomain 2
Zachary Charlop-Powers1, Lei Zeng, Qiang Zhang
1Department of Structural and Chemical Biology, Mount Sinai School of Medicine, 1425 Madison Avenue, Box 1677, New York, NY 10029, USA.
Cell Research
|April 7, 2010
Summary
The Polybromo (PB) protein
Area of Science:
- Biochemistry
- Molecular Biology
- Epigenetics
Background:
- The Polybromo (PB) protein is crucial for the human PBAF chromatin remodeling complex, impacting gene transcription.
- PB contains six bromodomains, which are known for binding acetyl-lysine residues.
- The specific histone-binding preferences of PB's bromodomains were previously unknown.
Purpose of the Study:
- To biochemically characterize the histone-binding specificity of all six PB bromodomains.
- To investigate the molecular mechanisms behind PB bromodomain-histone interactions.
Main Methods:
- Biochemical assays using lysine-acetylated peptides from human core histones.
- X-ray crystallography and Nuclear Magnetic Resonance (NMR) to determine protein structures.
Main Results:
- PB bromodomain 2 selectively binds to acetylated lysine 14 of histone H3 (H3K14ac).
- H3K14ac is a post-translational modification associated with gene transcriptional activation.
- Structural analysis revealed the molecular basis for bromodomain 2's H3K14ac recognition.
Conclusions:
- PB bromodomain 2 plays a specific role in recognizing the H3K14ac epigenetic mark.
- Understanding these interactions provides insight into chromatin remodeling and gene regulation.
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