HLA class II histocompatibility antigen, DR alpha chain (HLA-DRA) is a 254-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P01903.
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The mean pLDDT of this model is 89.2 (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 band | Meaning | Share of residues |
|---|---|---|
| Above 90 | Very high: backbone and side chains are usually accurate | 74% |
| 70 to 90 | Confident: backbone generally right | 11% |
| 50 to 70 | Low: treat with caution | 13% |
| Below 50 | Very low: often disordered regions | 2% |
What pLDDT means and how to read it
An alpha chain of antigen-presenting major histocompatibility complex class II (MHCII) molecule. In complex with the beta chain HLA-DRB, displays antigenic peptides on professional antigen presenting cells (APCs) for recognition by alpha-beta T cell receptor (TCR) on HLA-DR-restricted CD4-positive T cells. This guides antigen-specific T-helper effector functions, both antibody-mediated immune response and macrophage activation, to ultimately eliminate the infectious agents and transformed cells (PubMed:15265931, PubMed:15322540, PubMed:17334368, PubMed:22327072, PubMed:24190431, PubMed:27591323, PubMed:29884618, PubMed:31495665, PubMed:8145819, PubMed:9075930). Typically presents…
Heterotrimer that consists of an alpha chain HLA-DRA, a beta chain HLA-DRB and a peptide (peptide-MHCII) (PubMed:11080454, PubMed:11163233, PubMed:12244309, PubMed:16079912, PubMed:17583734, PubMed:18697946, PubMed:31619516, PubMed:32668259, PubMed:7477400, PubMed:9354468, PubMed:9782128). Newly synthesized alpha and beta chains forms a heterodimer (MHCII) that associates with the CD74/invariant…
Cell membrane, Endoplasmic reticulum membrane, Early endosome membrane, Late endosome membrane, Lysosome membrane, Autolysosome membrane
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 5NI9 | X-ray | 1.33 Å | A=26-206 |
| 4X5W | X-ray | 1.34 Å | A=26-217 |
| 5NIG | X-ray | 1.35 Å | A=26-206 |
| 8CMC | X-ray | 1.42 Å | A=26-207 |
| 8PJF | X-ray | 1.48 Å | A=26-207 |
| 6QZC | X-ray | 1.64 Å | AAA=28-207 |
| 8CMG | X-ray | 1.64 Å | A=26-207 |
| 8CMH | X-ray | 1.64 Å | A=26-207 |
| 4MD5 | X-ray | 1.65 Å | A=26-206 |
| 4MDJ | X-ray | 1.7 Å | A=26-206 |
| 8PJE | X-ray | 1.7 Å | A/D=26-207 |
| 7YX9 | X-ray | 1.76 Å | A/C=26-216 |
| 3C5J | X-ray | 1.8 Å | A=26-206 |
| 8PJG | X-ray | 1.83 Å | A=26-207 |
| 8CMB | X-ray | 1.84 Å | A=26-207 |
| 1FV1 | X-ray | 1.9 Å | A/D=26-206 |
| 6ATF | X-ray | 1.9 Å | A/D=26-206 |
| 6R0E | X-ray | 1.91 Å | AAA=26-207 |
| 1KLU | X-ray | 1.93 Å | A=29-207 |
| 3PDO | X-ray | 1.95 Å | A=26-217 |
Showing 20 of 140 experimental structures (best resolution first).
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