Interleukin-6 (IL6) is a 212-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P05231.
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The mean pLDDT of this model is 85.3 (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 band | Meaning | Share of residues |
|---|---|---|
| Above 90 | Very high: backbone and side chains are usually accurate | 65% |
| 70 to 90 | Confident: backbone generally right | 13% |
| 50 to 70 | Low: treat with caution | 18% |
| Below 50 | Very low: often disordered regions | 4% |
What pLDDT means and how to read it
Cytokine with a wide variety of biological functions in immunity, tissue regeneration, and metabolism. Binds to IL6R, then the complex associates to the signaling subunit IL6ST/gp130 to trigger the intracellular IL6-signaling pathway (Probable). The interaction with the membrane-bound IL6R and IL6ST stimulates 'classic signaling', whereas the binding of IL6 and soluble IL6R to IL6ST stimulates 'trans-signaling'. Alternatively, 'cluster signaling' occurs when membrane-bound IL6:IL6R complexes on transmitter cells activate IL6ST receptors on neighboring receiver cells (Probable)
Component of a hexamer of two molecules each of IL6, IL6R and IL6ST; first binds to IL6R to associate with the signaling subunit IL6ST (PubMed:12829785). Interacts with IL6R (via the N-terminal ectodomain); this interaction may be affected by IL6R-binding with SORL1, hence decreasing IL6 cis signaling (PubMed:28265003). Interacts with SORL1 (via the N-terminal ectodomain); this interaction leads…
Secreted
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 1ALU | X-ray | 1.9 Å | A=28-212 |
| 7NXZ | X-ray | 2.0 Å | AAA=30-212 |
| 4CNI | X-ray | 2.2 Å | C/D=42-212 |
| 4J4L | X-ray | 2.3 Å | C/D=47-212 |
| 4NI7 | X-ray | 2.4 Å | A=28-212 |
| 4O9H | X-ray | 2.42 Å | A=28-212 |
| 8YWQ | X-ray | 2.51 Å | A=28-212 |
| 4NI9 | X-ray | 2.55 Å | A/C=28-212 |
| 5FUC | X-ray | 2.7 Å | A/B=49-212 |
| 4ZS7 | X-ray | 2.93 Å | A=42-212 |
| 8YWR | X-ray | 2.93 Å | A=42-212 |
| 8QY5 | EM | 3.1 Å | B/E=1-212 |
| 8QY6 | EM | 3.16 Å | B/E=1-212 |
| 8D82 | EM | 3.22 Å | D/H=30-212 |
| 1P9M | X-ray | 3.65 Å | B=29-212 |
| 1IL6 | NMR | A=28-212 | |
| 2IL6 | NMR | A=28-212 |
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