P49917: DNA ligase 4 (LIG4)

DNA ligase 4 (LIG4) is a 911-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P49917.

Gene
LIG4
Organism
Homo sapiens
Length
911 residues
Mean pLDDT
88.2
Model
AF-P49917-F1 v6
Model created
1 Aug 2025
PDB structures
31

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Model confidence (pLDDT)

The mean pLDDT of this model is 88.2 (confident 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 accurate63%
70 to 90Confident: backbone generally right28%
50 to 70Low: treat with caution6%
Below 50Very low: often disordered regions3%

What pLDDT means and how to read it

Function

DNA ligase involved in DNA non-homologous end joining (NHEJ); required for double-strand break (DSB) repair and V(D)J recombination (PubMed:12517771, PubMed:17290226, PubMed:23523427, PubMed:29980672, PubMed:33586762, PubMed:8798671, PubMed:9242410, PubMed:9809069). Catalyzes the NHEJ ligation step of the broken DNA during DSB repair by resealing the DNA breaks after the gap filling is completed (PubMed:12517771, PubMed:17290226, PubMed:9242410, PubMed:9809069). Joins single-strand breaks in a double-stranded polydeoxynucleotide in an ATP-dependent reaction (PubMed:12517771, PubMed:17290226, PubMed:9242410, PubMed:9809069). LIG4 is mechanistically flexible: it can ligate nicks as well as…

Subunit structure

Interacts with XRCC4; the LIG4-XRCC4 subcomplex has a 1:2 stoichiometry and XRCC4 is required for LIG4 stability (PubMed:10854421, PubMed:11702069, PubMed:12517771, PubMed:17290226, PubMed:19332554, PubMed:19837014, PubMed:21982441, PubMed:22658747, PubMed:24984242, PubMed:25934149, PubMed:9259561, PubMed:9809069, PubMed:17567543). Component of the core long-range non-homologous end joining…

Subcellular location

Nucleus

Disease associations

Experimental structures in the PDB

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

PDB IDMethodResolutionChains and residues
4HTPX-ray2.25 ÅA/B=1-240
1IK9X-ray2.3 ÅC=748-784
3II6X-ray2.4 ÅX/Y=654-911
3W1BX-ray2.4 ÅA=1-609
6BKGX-ray2.4 ÅA=1-620
3W1GX-ray2.55 ÅA=1-609
7D9YX-ray2.76 ÅA=1-240
9CQ3EM2.8 ÅF/f=1-911
9N81EM2.8 ÅF/f=1-911
4HTOX-ray2.81 ÅA=1-240
3W5OX-ray2.84 ÅA/B=1-609
3VNNX-ray2.9 ÅA=268-406
7D9KX-ray2.9 ÅA=1-240
9CQ6EM3.1 ÅF/f=1-911
9N83EM3.1 ÅF/f=1-911
6BKFX-ray3.25 ÅA=1-620
9N82EM3.3 ÅF/f=1-911
9CQCEM3.4 ÅF/f=1-911
9IAXEM3.97 ÅK=1-911
7NFCEM4.14 ÅM/P=1-911

Showing 20 of 31 experimental structures (best resolution first).

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