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Visualization of Protein-protein Interaction in Nuclear and Cytoplasmic Fractions by Co-immunoprecipitation and In Situ Proximity Ligation Assay
Published on: January 16, 2017
Proliferating cell nuclear antigen structure and interactions: too many partners for one dancer?
Alfredo De Biasio1, Francisco J Blanco
1Structural Biology Unit, CIC bioGUNE, Derio, Spain.
Advances in Protein Chemistry and Structural Biology
|June 25, 2013
Summary
Proliferating cell nuclear antigen (PCNA) is a crucial DNA sliding clamp. This review focuses on the structural aspects of PCNA interactions with human proteins, highlighting unanswered questions in DNA metabolism.
Area of Science:
- Molecular Biology
- Structural Biology
- Biochemistry
Background:
- Proliferating cell nuclear antigen (PCNA) functions as a DNA sliding clamp essential for DNA replication and repair in eukaryotes and archaea.
- PCNA's toroidal structure encircles DNA, tethering replicative polymerases and serving as a platform for various DNA metabolic proteins.
- Protein interactions with PCNA often involve the PCNA Interaction Protein sequence (PIP-box), but the mechanisms of partner competition and functional regulation remain unclear.
Purpose of the Study:
- To review the current understanding of PCNA interactions from a structural perspective.
- To focus on interactions involving human proteins.
- To identify and highlight unresolved questions regarding PCNA-protein interactions and their functional implications.
Main Methods:
- Literature review of structural and biochemical studies on PCNA interactions.
- Analysis of known PCNA-binding motifs, such as the PIP-box.
- Examination of structural data for PCNA-protein complexes.
Main Results:
- Multiple proteins interact with PCNA, often via the PIP-box, suggesting a common binding mode.
- Structural studies reveal details of PCNA-DNA and PCNA-protein complexes.
- Discrepancies exist between reported interactions and observations in solution, suggesting indirect binding or weak direct interactions for some partners.
Conclusions:
- While the structural basis for some PCNA interactions is understood, the competition dynamics and functional outcomes of numerous protein interactions require further investigation.
- High-resolution structural and quantitative analyses are needed for many putative PCNA complexes.
- Understanding these interactions is critical for elucidating diverse DNA metabolic processes.
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