Nascent polypeptide-associated complex subunit alpha (NACA) is a 215-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: Q13765.
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The mean pLDDT of this model is 72.7 (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 | 42% |
| 70 to 90 | Confident: backbone generally right | 14% |
| 50 to 70 | Low: treat with caution | 18% |
| Below 50 | Very low: often disordered regions | 26% |
What pLDDT means and how to read it
Prevents inappropriate targeting of non-secretory polypeptides to the endoplasmic reticulum (ER). Binds to nascent polypeptide chains as they emerge from the ribosome and blocks their interaction with the signal recognition particle (SRP), which normally targets nascent secretory peptides to the ER. Also reduces the inherent affinity of ribosomes for protein translocation sites in the ER membrane (M sites). May act as a specific coactivator for JUN, binding to DNA and stabilizing the interaction of JUN homodimers with target gene promoters
Interacts with TBP and JUN (By similarity). Part of the nascent polypeptide-associated complex (NAC), which is a heterodimer of NACA and BTF3 (via NAC-A/B domains). NAC associates with ribosomes through the BTF3/NACB subunit and contacts the ribosomal protein L23, which is positioned near the exiting site. Both subunits can contact nascent polypeptide chains. NACA may also form homodimers, and…
Cytoplasm, Nucleus
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 3MCB | X-ray | 1.9 Å | A=79-132 |
| 9I2D | EM | 2.19 Å | NA=1-215 |
| 9S3D | EM | 2.32 Å | NA=1-215 |
| 9S3B | EM | 2.38 Å | NA=1-215 |
| 3MCE | X-ray | 2.4 Å | A/B/C/D=81-133 |
| 9S3C | EM | 2.42 Å | NA=1-215 |
| 9QLO | EM | 2.47 Å | NA=1-215 |
| 3LKX | X-ray | 2.5 Å | B=84-136 |
| 9QLQ | EM | 2.57 Å | NA=1-215 |
| 9MR4 | EM | 2.65 Å | EG=1-215 |
| 9QLP | EM | 2.75 Å | NA=1-215 |
| 9QQA | EM | 2.8 Å | Nt=1-215 |
| 9NDP | EM | 2.82 Å | EG=1-215 |
| 7QWQ | EM | 2.83 Å | t=1-215 |
| 7QWR | EM | 2.9 Å | t=1-215 |
| 8P2K | EM | 2.9 Å | Na=1-215 |
| 9I2E | EM | 2.95 Å | NA=1-215 |
| 9F1B | EM | 3.01 Å | Ct=1-215 |
| 9F1D | EM | 3.26 Å | Ct=1-215 |
| 7QWS | EM | 3.4 Å | t=1-215 |
Showing 20 of 24 experimental structures (best resolution first).
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