Crosstalk between site-specific modifications on p53 and histone H3
L J Warnock1, R Adamson, C J Lynch
1YCR p53 Research Group, Department of Biology, University of York, York, UK. ljw7@york.ac.uk
Oncogene
|September 25, 2007
Summary
Specific p53 modifications influence histone H3 changes. Mutations at serine 15 of p53 induced phosphorylation and altered histone H3 acetylation, impacting gene regulation.
Area of Science:
- Molecular Biology
- Cell Biology
- Epigenetics
Background:
- A link exists between p53 expression and histone H3 post-translational modifications.
- Understanding how p53 modifications impact histone modifications is crucial for deciphering gene regulation.
Purpose of the Study:
- To investigate if specific p53 post-translational modifications selectively impact histone H3 modifications.
- To screen for cooperative effects within p53 modifications.
Main Methods:
- Exogenous expression of wild-type and mutant p53 constructs (S15A, S15D, S37A, S37D) in HCT116 p53-/- cells.
- Analysis of p53 phosphorylation and endogenous histone H3 (H3) modifications (acetylation and methylation) using Western blotting.
- Comparison of modification patterns induced by different p53 mutants.
Main Results:
- p53 mutations at serine 15 (S15A, S15D) induced phosphorylation at S33, S37, and S46, while S37 mutations did not affect S33 phosphorylation.
- S46 phosphorylation was enhanced by p53(S37D) compared to p53(S37A).
- Expression of p53 constructs led to loss of H3 di-methylated K9; S15A, S15D, and S37A mutants selectively induced H3 acetylation at K9 and K14, unlike wild-type p53 or p53(S37D).
Conclusions:
- Specific p53 phosphorylation sites dictate downstream histone H3 modification patterns.
- p53 N-terminal phosphorylation mutants differentially affect histone H3 acetylation and methylation.
- These findings highlight the intricate interplay between p53 modifications and epigenetic regulation.
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