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Updated: Jun 25, 2026
12:47
Nuclear Magnetic Resonance Spectroscopy for the Identification of Multiple Phosphorylations of Intrinsically Disordered Proteins
Published on: December 27, 2016
Structural basis for p300 Taz2-p53 TAD1 binding and modulation by phosphorylation.
Hanqiao Feng1, Lisa M Miller Jenkins, Stewart R Durell
1Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, NIH, Bethesda, MD 20892, USA.
Structure (London, England : 1993)
|February 17, 2009
Summary
Researchers uncovered the structural basis of how p300 protein (a coactivator) binds to p53 protein (a tumor suppressor). This interaction is crucial for gene regulation and cancer research, highlighting key binding sites and the role of phosphorylation.
Area of Science:
- Molecular Biology
- Structural Biology
- Cancer Research
Background:
- Coactivators CREB-binding protein (CBP) and p300 are critical for p53-mediated transcriptional regulation.
- Detailed structural insights into the interaction between p300 domains and p53 have been lacking.
- Understanding these interactions is vital for deciphering gene regulation and developing cancer therapies.
Purpose of the Study:
- To determine the NMR structure of the complex formed between the Taz2 (C/H3) domain of p300 and the N-terminal transactivation domain of p53.
- To elucidate the molecular mechanisms underlying the interaction and stabilization of the p53-p300 complex.
- To investigate the role of post-translational modifications, specifically phosphorylation, in modulating this interaction.
Main Methods:
- Nuclear Magnetic Resonance (NMR) spectroscopy was employed to determine the three-dimensional structure of the complex.
- Mutational analyses were conducted to identify key residues involved in complex stabilization.
- Thermodynamic experiments were performed to quantify the binding affinities and energetics.
Main Results:
- The NMR structure reveals that p53 forms an alpha helix that interacts with the p300 Taz2 domain via an extended surface.
- Hydrophobic residues play a significant role in stabilizing the complex.
- Phosphorylation of p53 at Thr(18) enhances binding affinity to Taz2 through electrostatic interactions with arginine residues, while phosphorylation at Ser(15) and Thr(18) highlights the importance of hydrophobic interactions.
Conclusions:
- The study provides the first detailed structural view of the p53-p300 Taz2 domain interaction.
- The findings highlight the critical roles of both hydrophobic and electrostatic interactions, modulated by p53 phosphorylation, in governing the p53-p300 complex formation.
- This structural and mechanistic understanding is fundamental for comprehending p53 transcriptional regulation and offers potential targets for cancer drug development.
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