GTF2B

This gene encodes the general transcription factor IIB, one of the ubiquitous factors required for transcription initiation by RNA polymerase II. The protein localizes to the nucleus where it forms a complex (the DAB complex) with transcription factors IID and IIA. Transcription factor IIB serves as a bridge between IID, the factor which initially recognizes the promoter sequence, and RNA polymerase II.

general transcription factor IIB

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:1876184, PubMed:1946368, PubMed:1517211, PubMed:3818643, PubMed:3029109, PubMed:8413225, PubMed:8515820, PubMed:8516311, PubMed:8516312, PubMed:7601352, PubMed:9420329, PubMed:12931194, PubMed:27193682).

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:8504927, PubMed:8413225, PubMed:8515820, PubMed:8516311, PubMed:8516312).

Released from the PIC early following the onset of transcription during the initiation and elongation transition and reassociates with TBP during the next transcription cycle (PubMed:7601352).

Associates with chromatin to core promoter-specific regions (PubMed:12931194, PubMed:24441171).

Binds to two distinct DNA core promoter consensus sequence elements in a TBP-independent manner; these IIB-recognition elements (BREs) are localized immediately upstream (BREu), 5'-[GC][GC][GA]CGCC-3', and downstream (BREd), 5'-[GA]T[TGA][TG][GT][TG][TG]-3', of the TATA box element (PubMed:9420329, PubMed:16230532, PubMed:7675079, PubMed:10619841).

Modulates transcription start site selection (PubMed:10318856).

Exhibits also autoacetyltransferase activity that contributes to the activated transcription (PubMed:12931194).

DNA-templated transcription, initiation Source: GO_Central
Positive regulation of core promoter binding Source: GO_Central
Protein acetylation Source: UniProtKB
RNA polymerase II core complex assembly Source: UniProtKB
RNA polymerase II preinitiation complex assembly Source: UniProtKB
Transcriptional start site selection at RNA polymerase II promoter Source: UniProtKB
Transcription by RNA polymerase II Source: ARUK-UCL
Transcription initiation from RNA polymerase II promoter Source: UniProtKB
Viral transcription Source: GO_Central

Nucleus; Chromosome. Non-acetylated form colocalizes with DNA in the G0/1, S and G2 phases of the cell cycle, but not during mitosis (PubMed:24441171). Acetylated form colocalizes at transcriptionally silent mitotic chromatids during mitosis at metaphase, anaphase, and telophase phases of the cell cycle (PubMed:24441171).

Acetylated (PubMed:24441171). Autoacetylated; autoacetylation at Lys-238 stimulates transcription activation (PubMed:12931194).