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Updated: Jun 19, 2026
14:57
Yeast As a Chassis for Developing Functional Assays to Study Human P53
Published on: August 4, 2019
Structural evolution of p53, p63, and p73: implication for heterotetramer formation
Andreas C Joerger1, Sridharan Rajagopalan, Eviatar Natan
1Centre for Protein Engineering, Medical Research Council, Hills Road, Cambridge CB2 0QH, United Kingdom.
Summary
The p53 family of transcription factors (p53, p63, and p73) form tetramers. A unique C-terminal helix in p73 stabilizes its tetramer structure, influencing p53 family evolution and function.
Area of Science:
- Molecular Biology
- Structural Biology
- Genetics
Background:
- Transcription factors p53, p63, and p73 are crucial for cell-cycle control and development.
- Oligomerization, specifically tetramer formation, is essential for the distinct functions of p53 family members.
Purpose of the Study:
- To elucidate the molecular basis of tetramer formation in the p53 family.
- To understand the structural differences and evolutionary divergence of the tetramerization domains.
Main Methods:
- Crystal structure determination of the human p73 tetramerization domain.
- Mass spectrometry to analyze tetramer exchange dynamics.
Main Results:
- p73 forms a D(2) symmetric tetramer, similar to p53, described as a dimer of dimers.
- p73 possesses an additional C-terminal helix absent in p53, which stabilizes the tetramer architecture.
- Mass spectrometry revealed that p63 and p73 tetramerization domains undergo full exchange, forming mixed tetramers, unlike p53.
Conclusions:
- The C-terminal helix in p73 acts as a clamp, crucial for tetramer stability.
- Divergent evolution of the oligomerization domain led to p53's smaller, less promiscuous building blocks, enabling functional pathway separation.
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