Q8C6L5: Cyclic GMP-AMP synthase (Cgas)

Cyclic GMP-AMP synthase (Cgas) is a 507-residue protein from Mus musculus. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: Q8C6L5.

Gene
Cgas
Organism
Mus musculus
Length
507 residues
Mean pLDDT
78.3
Model
AF-Q8C6L5-F1 v6
Model created
1 Aug 2025
PDB structures
55

Explore in 3D Color by confidence AlphaFold DB UniProt

Model confidence (pLDDT)

The mean pLDDT of this model is 78.3 (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 accurate58%
70 to 90Confident: backbone generally right12%
50 to 70Low: treat with caution1%
Below 50Very low: often disordered regions28%

What pLDDT means and how to read it

Function

Nucleotidyltransferase that catalyzes the formation of cyclic GMP-AMP (2',3'-cGAMP) from ATP and GTP and plays a key role in innate immunity (PubMed:23258413, PubMed:23647843, PubMed:23722158, PubMed:26829768, PubMed:28214358, PubMed:29426904, PubMed:29625897, PubMed:32814054, PubMed:38740774). Catalysis involves both the formation of a 2',5' phosphodiester linkage at the GpA step and the formation of a 3',5' phosphodiester linkage at the ApG step, producing c[G(2',5')pA(3',5')p] (PubMed:23258413, PubMed:23647843, PubMed:23722158, PubMed:26829768, PubMed:28214358). Acts as a key DNA sensor: directly binds double-stranded DNA (dsDNA), inducing the formation of liquid-like droplets in which…

Subunit structure

Monomer in the absence of DNA (PubMed:28214358). Homodimer in presence of dsDNA: forms a 2:2 dimer with two enzymes binding to two DNA molecules (PubMed:28902841, PubMed:29426904). Interacts with nucleosomes; interaction is mainly mediated via histones H2A and H2B and inactivates the nucleotidyltransferase activity by blocking DNA-binding and subsequent activation (PubMed:32911480,…

Subcellular location

Nucleus, Chromosome, Cell membrane, Cytoplasm, cytosol

Experimental structures in the PDB

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

PDB IDMethodResolutionChains and residues
8SHKX-ray1.71 ÅC=147-507
8SHUX-ray1.71 ÅC=147-507
8SHYX-ray1.77 ÅC=147-507
5XZGX-ray1.83 ÅA=147-507
4O6AX-ray1.86 ÅA/B=147-507
4K98X-ray1.94 ÅA=147-507
4K99X-ray1.95 ÅA=147-507
4K8VX-ray2.0 ÅA/B/C/D=147-507
7UTTX-ray2.04 ÅA/C=147-507
4K96X-ray2.08 ÅA/B=147-507
5XZBX-ray2.13 ÅA=149-505
7BUJX-ray2.13 ÅA/B=61-507
5XZEX-ray2.18 ÅA=147-507
8SJ2X-ray2.23 ÅA/C=147-507
4K9AX-ray2.26 ÅA=147-507
4K9BX-ray2.26 ÅA=147-507
7UUXX-ray2.26 ÅA/C=147-507
8G1JX-ray2.3 ÅA/C=147-507
4LEZX-ray2.36 ÅA/C=142-507
8G2QX-ray2.37 ÅA/C=147-507

Showing 20 of 55 experimental structures (best resolution first).

More AlphaFold highlights

About this viewer

MolViewer loads the AlphaFold model straight from AlphaFold DB into your browser. Show it as a cartoon, color by pLDDT, measure distances and angles, and load a PDB structure next to it to compare.