T-cell surface glycoprotein CD4 (CD4) is a 458-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P01730.
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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 | 19% |
| 50 to 70 | Low: treat with caution | 8% |
| Below 50 | Very low: often disordered regions | 9% |
What pLDDT means and how to read it
Integral membrane glycoprotein that plays an essential role in the immune response and serves multiple functions in responses against both external and internal offenses. In T-cells, functions primarily as a coreceptor for MHC class II molecule:peptide complex. The antigens presented by class II peptides are derived from extracellular proteins while class I peptides are derived from cytosolic proteins. Interacts simultaneously with the T-cell receptor (TCR) and the MHC class II presented by antigen presenting cells (APCs). In turn, recruits the Src kinase LCK to the vicinity of the TCR-CD3 complex. LCK then initiates different intracellular signaling pathways by phosphorylating various…
Forms disulfide-linked homodimers at the cell surface. Interacts with LCK (PubMed:16888650). Interacts with PTK2/FAK1 (PubMed:18078954). Binds to P4HB/PDI. Interacts with IL16; this interaction induces a CD4-dependent signaling in lymphocytes (PubMed:1673145). Interacts (via Ig-like V-type domain) with MHCII alpha chain (via alpha-2 domain) and beta chain (via beta-2 domain); this interaction…
Cell membrane
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 8W90 | X-ray | 1.81 Å | B/D/F=26-203 |
| 4H8W | X-ray | 1.85 Å | C=26-208 |
| 2NY1 | X-ray | 1.99 Å | B=26-208 |
| 1CDY | X-ray | 2.0 Å | A=26-203 |
| 2NXY | X-ray | 2.0 Å | B=26-208 |
| 2NY2 | X-ray | 2.0 Å | B=26-208 |
| 2NY3 | X-ray | 2.0 Å | B=26-208 |
| 2NY4 | X-ray | 2.0 Å | B=26-208 |
| 2NXZ | X-ray | 2.04 Å | B=26-208 |
| 3S5L | X-ray | 2.1 Å | G/H=26-203 |
| 3O2D | X-ray | 2.19 Å | A=26-207 |
| 1G9M | X-ray | 2.2 Å | C=26-210 |
| 1RZJ | X-ray | 2.2 Å | C=26-210 |
| 2NY0 | X-ray | 2.2 Å | B=26-208 |
| 3CD4 | X-ray | 2.2 Å | A=26-207 |
| 1CDH | X-ray | 2.3 Å | A=26-203 |
| 3S4S | X-ray | 2.4 Å | G/H=26-203 |
| 6L1Y | X-ray | 2.47 Å | C=26-202 |
| 1CDJ | X-ray | 2.5 Å | A=26-203 |
| 1GC1 | X-ray | 2.5 Å | C=26-210 |
Showing 20 of 84 experimental structures (best resolution first).
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