Proliferating cell nuclear antigen (PCNA) is a 261-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P12004.
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The mean pLDDT of this model is 94.3 (very high overall). pLDDT is AlphaFold's per-residue confidence score from 0 to 100. In MolViewer, choose the B-factor color scheme to color the model by pLDDT, because AlphaFold stores it in the B-factor column.
| pLDDT band | Meaning | Share of residues |
|---|---|---|
| Above 90 | Very high: backbone and side chains are usually accurate | 89% |
| 70 to 90 | Confident: backbone generally right | 9% |
| 50 to 70 | Low: treat with caution | 1% |
| Below 50 | Very low: often disordered regions | 2% |
What pLDDT means and how to read it
Confers DNA tethering and processivity to DNA polymerases and other proteins (PubMed:24695737, PubMed:24939902, PubMed:35585232). Auxiliary protein of DNA polymerase delta and epsilon, is involved in the control of DNA replication by increasing the polymerases' processivity during elongation of the leading strand (PubMed:35585232). Induces a robust stimulatory effect on the 3'-5' exonuclease and 3'-phosphodiesterase, but not apurinic-apyrimidinic (AP) endonuclease, APEX2 activities. Has to be loaded onto DNA in order to be able to stimulate APEX2. Plays a key role in DNA damage response (DDR) by being conveniently positioned at the replication fork to coordinate DNA replication with DNA…
Homotrimer (PubMed:24939902). Interacts with p300/EP300; the interaction occurs on chromatin in UV-irradiated damaged cells (PubMed:24939902). Interacts with CREBBP (via transactivation domain and C-terminus); the interaction occurs on chromatin in UV-irradiated damaged cells (PubMed:24939902). Directly interacts with POLD1, POLD3 and POLD4 subunits of the DNA polymerase delta complex, POLD3…
Nucleus
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 1U7B | X-ray | 1.88 Å | A=1-261 |
| 8F5Q | X-ray | 1.9 Å | A/C/E=1-259 |
| 9N3L | X-ray | 1.9 Å | A=1-261 |
| 5E0U | X-ray | 1.93 Å | A/B/C=1-261 |
| 5MLO | X-ray | 1.96 Å | A/C/E=1-261 |
| 4RJF | X-ray | 2.01 Å | A/C/E=1-261 |
| 5E0V | X-ray | 2.07 Å | A/B=1-261 |
| 3VKX | X-ray | 2.1 Å | A=1-261 |
| 6HVO | X-ray | 2.1 Å | A/B/C=1-261 |
| 4ZTD | X-ray | 2.2 Å | A/B/C=2-254 |
| 5YCO | X-ray | 2.2 Å | A/B/C/D=1-261 |
| 5MOM | X-ray | 2.27 Å | A/B/C=1-258 |
| 1VYM | X-ray | 2.3 Å | A/B/C=1-261 |
| 2ZVM | X-ray | 2.3 Å | A/B/C=1-261 |
| 5YD8 | X-ray | 2.3 Å | X/Y/Z=1-261 |
| 6K3A | X-ray | 2.3 Å | A/C/E=1-261 |
| 7KQ0 | X-ray | 2.4 Å | A/C/E=1-259 |
| 5MLW | X-ray | 2.45 Å | A/C/E=1-261 |
| 2ZVL | X-ray | 2.5 Å | A/B/C/D/E/F=1-261 |
| 5MAV | X-ray | 2.58 Å | A/B/C/D/E/F=1-261 |
Showing 20 of 102 experimental structures (best resolution first).
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