P18887: DNA repair protein XRCC1 (XRCC1)

DNA repair protein XRCC1 (XRCC1) is a 633-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P18887.

Gene
XRCC1
Organism
Homo sapiens
Length
633 residues
Mean pLDDT
69.4
Model
AF-P18887-F1 v6
Model created
1 Aug 2025
PDB structures
13

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Model confidence (pLDDT)

The mean pLDDT of this model is 69.4 (low 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 bandMeaningShare of residues
Above 90Very high: backbone and side chains are usually accurate39%
70 to 90Confident: backbone generally right14%
50 to 70Low: treat with caution12%
Below 50Very low: often disordered regions35%

What pLDDT means and how to read it

Function

Scaffold protein involved in DNA single-strand break repair by mediating the assembly of DNA break repair protein complexes (PubMed:11163244, PubMed:28002403). Negatively regulates ADP-ribosyltransferase activity of PARP1 during base-excision repair in order to prevent excessive PARP1 activity (PubMed:28002403, PubMed:34102106, PubMed:34811483). Recognizes and binds poly-ADP-ribose chains: specifically binds auto-poly-ADP-ribosylated PARP1, limiting its activity (PubMed:14500814, PubMed:34102106, PubMed:34811483)

Subunit structure

Homodimer (PubMed:16397295). Interacts with polynucleotide kinase (PNK), DNA polymerase-beta (POLB) and DNA ligase III (LIG3) (PubMed:19155274, PubMed:19336415). Interacts with APTX and APLF (PubMed:14755728, PubMed:15044383, PubMed:15380105, PubMed:17353262, PubMed:17507382). Interacts with APEX1; the interaction is induced by SIRT1 and increases with the acetylated form of APEX1…

Subcellular location

Nucleus, Chromosome

Disease associations

Experimental structures in the PDB

Compare the prediction with experimentally determined structures of the same protein:

PDB IDMethodResolutionChains and residues
2W3OX-ray1.85 ÅC/D=515-522
5W7XX-ray2.0 ÅE/F/G/H=514-522
5W7YX-ray2.1 ÅC/D=514-521
5E6QX-ray2.31 ÅA=241-276
3LQCX-ray2.35 ÅA=1-183
6WH1X-ray2.4 ÅA=538-633
6WH2X-ray2.41 ÅA/B=538-633
3K77X-ray2.6 ÅA/B/C/D/E/F/G/H=1-155
3K75X-ray2.95 ÅB/C=1-183
1CDZX-ray3.2 ÅA=538-633
1XNANMRA=1-183
1XNTNMRA=1-183
2D8MNMRA=304-420

More AlphaFold highlights

About this viewer

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