Paired amphipathic helix protein Sin3b (SIN3B) is a 1162-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: O75182.
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The mean pLDDT of this model is 68.0 (low 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 | 23% |
| 70 to 90 | Confident: backbone generally right | 34% |
| 50 to 70 | Low: treat with caution | 16% |
| Below 50 | Very low: often disordered regions | 27% |
What pLDDT means and how to read it
Acts as a transcriptional repressor. Interacts with MXI1 to repress MYC responsive genes and antagonize MYC oncogenic activities. Interacts with MAD-MAX heterodimers by binding to MAD. The heterodimer then represses transcription by tethering SIN3B to DNA. Also forms a complex with FOXK1 which represses transcription. With FOXK1, regulates cell cycle progression probably by repressing cell cycle inhibitor genes expression. As part of the SIN3B complex represses transcription and counteracts the histone acetyltransferase activity of EP300 through the recognition H3K27ac marks by PHF12 and the activity of the histone deacetylase HDAC2 (PubMed:37137925). SIN3B complex is recruited downstream…
Component of the SIN3B complex, which includes SIN3B, HDAC2 or HDAC1, PHF12 and MORF4L1 (PubMed:21041482, PubMed:37137925). Interacts with FOXK1/MNF, MXI, MAD, NCOR1 and SAP30. Interaction with SUDS3 enhances the interaction with HDAC1 to form a complex. Interacts with CRY1, HCFC1, MAD3, MAD4, MAEL, REST, RNF220 and SETDB1. Interacts with C6orf89 (PubMed:23460338). Interacts with MYT1L (By…
Nucleus
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 8BPB | EM | 2.8 Å | A=1-1162 |
| 8BPC | EM | 2.8 Å | A=1-1162 |
| 8C60 | EM | 3.4 Å | A=1-1162 |
| 8BPA | EM | 3.7 Å | A=1-1162 |
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