| Full protein name | Bromodomain-containing protein 4;Protein HUNK1 |
| Gene name | BRD4;HUNK1 |
| Species | Homo sapiens |
| Localization | Nucleus; Chromosome. |
| Description | Chromatin reader protein that recognizes and binds acetylated histones and plays a key role in transmission of epigenetic memory across cell divisions and transcription regulation. Remains associated with acetylated chromatin throughout the entire cell cycle and provides epigenetic memory for postmitotic G1 gene transcription by preserving acetylated chromatin status and maintaining high-order chromatin structure. During interphase, plays a key role in regulating the transcription of signal-inducible genes by associating with the P-TEFb complex and recruiting it to promoters: BRD4 is required to form the transcriptionally active P-TEFb complex by displacing negative regulators such as HEXIM1 and 7SKsnRNA complex from P-TEFb, thereby transforming it into an active form that can then phosphorylate the C-terminal domain (CTD) of RNA polymerase II. Promotes phosphorylation of 'Ser-2' of the C-terminal domain (CTD) of RNA polymerase II. According to a report, directly acts as an atypical protein kinase and mediates phosphorylation of 'Ser-2' of the C-terminal domain (CTD) of RNA polymerase II; these data however need additional evidences in vivo. In addition to acetylated histones, also recognizes and binds acetylated RELA, leading to further recruitment of the P-TEFb complex and subsequent activation of NF-kappa-B. Also acts as a regulator of p53/TP53-mediated transcription: following phosphorylation by CK2, recruited to p53/TP53 specific target promoters. BRD4 and MED1 contain large intrinsically disordered regions (IDRs), including high proline and glutamine content (BRD4), high serine content (MED1), and acidic and basic regions (BRD4 and MED1). |
| GO term | GO:0003682; chromatin binding; IDA:UniProtKB. GO:0019899; enzyme binding; IPI:UniProtKB. GO:0070577; lysine-acetylated histone binding; IDA:UniProtKB. GO:0106140; P-TEFb complex binding; IDA:FlyBase. GO:0002039; p53 binding; IDA:UniProtKB. GO:0099122; RNA polymerase II C-terminal domain binding; IDA:MGI. GO:0008353; RNA polymerase II CTD heptapeptide repeat kinase activity; IMP:MGI. GO:0003713; transcription coactivator activity; IMP:UniProtKB. GO:0003712; transcription coregulator activity; IMP:UniProtKB. |
| Full sequence length | 1362 |
| Database linked | MobiDB :O60885 DisProt :DP01898 IDEAL :IID00111 OMIM :608749 |
| IDR Region | 1 1362 |
| LCR Region | 1 1362 |