HLA class I histocompatibility antigen, A alpha chain (HLA-A) is a 365-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P04439.
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The mean pLDDT of this model is 87.1 (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 | 75% |
| 70 to 90 | Confident: backbone generally right | 8% |
| 50 to 70 | Low: treat with caution | 4% |
| Below 50 | Very low: often disordered regions | 13% |
What pLDDT means and how to read it
Antigen-presenting major histocompatibility complex class I (MHCI) molecule. In complex with B2M/beta 2 microglobulin displays primarily viral and tumor-derived peptides on antigen-presenting cells for recognition by alpha-beta T cell receptor (TCR) on HLA-A-restricted CD8-positive T cells, guiding antigen-specific T cell immune response to eliminate infected or transformed cells (PubMed:10449296, PubMed:12138174, PubMed:12393434, PubMed:1402688, PubMed:15893615, PubMed:17189421, PubMed:19543285, PubMed:21498667, PubMed:24192765, PubMed:24395804, PubMed:2456340, PubMed:2784196, PubMed:28250417, PubMed:7504010, PubMed:7694806, PubMed:9862734). May also present self-peptides derived from the…
Heterotrimer that consists of an alpha chain HLA-A, a beta chain B2M and a peptide (peptide-HLA-A-B2M) (PubMed:11502003, PubMed:18275829, PubMed:19177349, PubMed:19542454, PubMed:21943705, PubMed:22245737, PubMed:24395804, PubMed:26758806, PubMed:28250417, PubMed:7504010, PubMed:7506728, PubMed:7679507, PubMed:7694806, PubMed:7935798, PubMed:8805302, PubMed:8906788, PubMed:9177355). Early in…
Cell membrane, Endoplasmic reticulum membrane
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 3MRE | X-ray | 1.1 Å | A=25-304 |
| 3D25 | X-ray | 1.3 Å | A=25-298 |
| 3MRG | X-ray | 1.3 Å | A=25-304 |
| 6JOZ | X-ray | 1.35 Å | A=25-299 |
| 5C0G | X-ray | 1.37 Å | A=25-299 |
| 5N1Y | X-ray | 1.39 Å | A=25-299 |
| 1I4F | X-ray | 1.4 Å | A=25-299 |
| 1OGA | X-ray | 1.4 Å | A=25-299 |
| 3MRB | X-ray | 1.4 Å | A=25-299 |
| 3MRK | X-ray | 1.4 Å | A=25-304 |
| 6J2A | X-ray | 1.4 Å | A=25-298 |
| 1X7Q | X-ray | 1.45 Å | A=25-299 |
| 5C0F | X-ray | 1.46 Å | A=25-299 |
| 4U6Y | X-ray | 1.47 Å | A=25-299 |
| 5C0E | X-ray | 1.49 Å | A=25-299 |
| 5DDH | X-ray | 1.5 Å | A=25-298 |
| 6J1W | X-ray | 1.5 Å | A=25-298 |
| 6Q3K | X-ray | 1.5 Å | A=24-299 |
| 5C0I | X-ray | 1.53 Å | A=25-299 |
| 5EU5 | X-ray | 1.54 Å | A=25-299 |
Showing 20 of 403 experimental structures (best resolution first).
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