HLA class II histocompatibility antigen, DRB1 beta chain (HLA-DRB1) is a 266-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P01911.
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The mean pLDDT of this model is 88.4 (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 | 71% |
| 70 to 90 | Confident: backbone generally right | 13% |
| 50 to 70 | Low: treat with caution | 11% |
| Below 50 | Very low: often disordered regions | 5% |
What pLDDT means and how to read it
A beta chain of antigen-presenting major histocompatibility complex class II (MHCII) molecule. In complex with the alpha chain HLA-DRA, displays antigenic peptides on professional antigen presenting cells (APCs) for recognition by alpha-beta T cell receptor (TCR) on HLA-DRB1-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:16148104, PubMed:22327072, PubMed:27591323, PubMed:29884618, PubMed:31495665, PubMed:8642306). Typically presents extracellular peptide antigens of 10 to 30 amino acids…
Heterotrimer that consists of an alpha chain HLA-DRA, a beta chain HLA-DRB1 and a peptide (peptide-MHCII) (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 chain (Ii) in the endoplasmic reticulum (ER). Ii is a trimer composed of three subunits and each…
Cell membrane, Endoplasmic reticulum membrane, Lysosome membrane, Late endosome 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 | B=30-219 |
| 4X5W | X-ray | 1.34 Å | B=30-227 |
| 5NIG | X-ray | 1.35 Å | B=30-219 |
| 8PJF | X-ray | 1.48 Å | B=30-219 |
| 6QZC | X-ray | 1.64 Å | BBB=30-219 |
| 4MD5 | X-ray | 1.65 Å | B=30-219 |
| 4MDJ | X-ray | 1.7 Å | B=30-219 |
| 8PJE | X-ray | 1.7 Å | B/E=30-219 |
| 8PJG | X-ray | 1.83 Å | B=30-219 |
| 6R0E | X-ray | 1.91 Å | BBB=30-219 |
| 1KLU | X-ray | 1.93 Å | B=30-219 |
| 3PDO | X-ray | 1.95 Å | B=30-227 |
| 4MD4 | X-ray | 1.95 Å | B=30-219 |
| 6HBY | X-ray | 1.95 Å | B/E=30-219 |
| 5JLZ | X-ray | 1.99 Å | B/D=30-219 |
| 1D5M | X-ray | 2.0 Å | B=30-221 |
| 1D5Z | X-ray | 2.0 Å | B=30-221 |
| 2G9H | X-ray | 2.0 Å | B=30-219 |
| 4MDI | X-ray | 2.0 Å | B=30-219 |
| 6CPN | X-ray | 2.0 Å | B=30-219 |
Showing 20 of 108 experimental structures (best resolution first).
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