Transcription initiation factor IIB (GTF2B) is a 316-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: Q00403.
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The mean pLDDT of this model is 87.3 (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 | 67% |
| 70 to 90 | Confident: backbone generally right | 23% |
| 50 to 70 | Low: treat with caution | 6% |
| Below 50 | Very low: often disordered regions | 4% |
What pLDDT means and how to read it
General transcription factor that plays a role in transcription initiation by RNA polymerase II (Pol II). Involved in the pre-initiation complex (PIC) formation and Pol II recruitment at promoter DNA (PubMed:12931194, PubMed:1517211, PubMed:1876184, PubMed:1946368, PubMed:27193682, PubMed:3029109, PubMed:3818643, PubMed:7601352, PubMed:8413225, PubMed:8515820, PubMed:8516311, PubMed:8516312, PubMed:9420329). Together with the TATA box-bound TBP forms the core initiation complex and provides a bridge between TBP and the Pol II-TFIIF complex (PubMed:8413225, PubMed:8504927, PubMed:8515820, PubMed:8516311, PubMed:8516312). Released from the PIC early following the onset of transcription…
Found in a ternary complex with TATA box-bound TBP (PubMed:10619841, PubMed:29158257, PubMed:8413225, PubMed:8515820, PubMed:8516311, PubMed:8516312). Part of a TFIID-containing RNA polymerase II pre-initiation complex (PIC) that is composed of TBP and at least GTF2A1, GTF2A2, GTF2E1, GTF2E2, GTF2F1, GTF2H2, GTF2H3, GTF2H4, GTF2H5, GTF2B, TCEA1, ERCC2, ERCC3, TAF1, TAF2, TAF3, TAF4, TAF5, TAF6,…
Nucleus, Chromosome
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 7NVU | EM | 2.5 Å | M=1-316 |
| 1C9B | X-ray | 2.65 Å | A/E/I/M/Q=110-316 |
| 1VOL | X-ray | 2.7 Å | A=113-316 |
| 7NVS | EM | 2.8 Å | M=1-316 |
| 7NVT | EM | 2.9 Å | M=1-316 |
| 8S52 | EM | 2.9 Å | M=1-316 |
| 7ZWD | EM | 3.0 Å | M=1-316 |
| 7ZX8 | EM | 3.0 Å | M=1-316 |
| 8S51 | EM | 3.1 Å | M=1-316 |
| 7ZWC | EM | 3.2 Å | M=1-316 |
| 7EGB | EM | 3.3 Å | R=1-316 |
| 5WH1 | X-ray | 3.39 Å | A/B/C/D=107-316 |
| 7ZX7 | EM | 3.4 Å | M=1-316 |
| 8S5N | EM | 3.4 Å | M=1-316 |
| 7ZXE | EM | 3.5 Å | M=1-316 |
| 7EG9 | EM | 3.7 Å | R=1-316 |
| 8BZ1 | EM | 3.8 Å | M=1-316 |
| 5IYB | EM | 3.9 Å | M=1-316 |
| 5IYC | EM | 3.9 Å | M=1-316 |
| 5IYD | EM | 3.9 Å | M=1-316 |
Showing 20 of 55 experimental structures (best resolution first).
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