Small t antigen is a 174-residue protein from Simian virus 40. This is its AlphaFold structure prediction, created 3 Jul 2025. UniProt accession: P03081.
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The mean pLDDT of this model is 85.5 (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 | 59% |
| 70 to 90 | Confident: backbone generally right | 28% |
| 50 to 70 | Low: treat with caution | 4% |
| Below 50 | Very low: often disordered regions | 9% |
What pLDDT means and how to read it
Promotes efficient viral genome replication by accelerating both G1 and S phase progression of the cell cycle. Inhibits host PP2A by binding to the A subunit, thereby displacing lower affinity regulatory B subunit. Inactivation of PP2A in turn results in the transactivation of cyclin A and cyclin D1 promoters. Late during the infection cycle, ST may induce dephosphorylation of host eIF4E-binding protein EIF4EBP1 leading to the inhibition of cap-dependent translation. May establish and maintain high levels of viral genomes during persistent infection in cell culture
Interacts with host PPP2R1A; the interaction inhibits PP2A activity
Host cytoplasm, Host nucleus
Compare the prediction with experimentally determined structures of the same protein:
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