UniProt functional annotation for Q00403



	UniProt functional annotation for Q00403

UniProt code: Q00403.

Organism: Homo sapiens (Human).

Taxonomy: Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo.

Function: 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). {ECO:0000269|PubMed:10318856, ECO:0000269|PubMed:10619841, ECO:0000269|PubMed:12931194, ECO:0000269|PubMed:1517211, ECO:0000269|PubMed:16230532, ECO:0000269|PubMed:1876184, ECO:0000269|PubMed:1946368, ECO:0000269|PubMed:24441171, ECO:0000269|PubMed:27193682, ECO:0000269|PubMed:3029109, ECO:0000269|PubMed:3818643, ECO:0000269|PubMed:7601352, ECO:0000269|PubMed:7675079, ECO:0000269|PubMed:8413225, ECO:0000269|PubMed:8504927, ECO:0000269|PubMed:8515820, ECO:0000269|PubMed:8516311, ECO:0000269|PubMed:8516312, ECO:0000269|PubMed:9420329}.

Catalytic activity: Reaction=acetyl-CoA + L-lysyl-[protein] = CoA + H(+) + N(6)-acetyl-L- lysyl-[protein]; Xref=Rhea:RHEA:45948, Rhea:RHEA-COMP:9752, Rhea:RHEA-COMP:10731, ChEBI:CHEBI:15378, ChEBI:CHEBI:29969, ChEBI:CHEBI:57287, ChEBI:CHEBI:57288, ChEBI:CHEBI:61930; EC=2.3.1.48; Evidence={ECO:0000269|PubMed:12931194};

Biophysicochemical properties: Kinetic parameters: KM=0.117 mM for acetyl-CoA {ECO:0000269|PubMed:12931194};

Subunit: Found in a ternary complex with TATA box-bound TBP (PubMed:8413225, PubMed:8515820, PubMed:8516311, PubMed:8516312, PubMed:10619841, PubMed:29158257). 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, TAF7, TAF8, TAF9, TAF10, TAF11, TAF12 and TAF13 (PubMed:27193682). Associates with TFIID-TFIIA (DA complex) to form TFIID-TFIIA-TFIIB (DAB complex), which is then recognized by RNA polymerase II (Pol II) (PubMed:1876184, PubMed:2247058). Found in a RNA polymerase II initiation complex (PubMed:3818643, PubMed:3029109, PubMed:8413225, PubMed:8516312, PubMed:7601352). Interacts (via C- terminus) with TBP; this interaction with TATA box-bound TBP guides Pol II into the PIC (PubMed:8504927, PubMed:10619841). Interacts (via N- terminus) with Pol II (PubMed:8504927, PubMed:8413225). Interacts (via C-terminus) with SSU72; this interaction is inhibited by SYMPK (PubMed:29158257). Interacts with NR2F1; this interaction is direct (PubMed:1517211). Interacts with PGR (PubMed:1517211). Interacts with ESR1 (PubMed:1517211). Interacts with GTF2F1 (via C-terminus and preferentially via acetylated form); this interaction prevents binding of GTF2B to GTF2F2 (PubMed:8662660, PubMed:12931194). Interacts with GTF2F2 (via N-terminus); this interaction is inhibited in presence of GTF2F1 (PubMed:8504927, PubMed:8662660). Interacts with the transcription elongation factor TCEA2 (PubMed:8566795). Interacts with HSF1 (via transactivation domain) (PubMed:11005381). Interacts with GPBP1 (By similarity). {ECO:0000250|UniProtKB:P62915, ECO:0000269|PubMed:10619841, ECO:0000269|PubMed:11005381, ECO:0000269|PubMed:12931194, ECO:0000269|PubMed:1517211, ECO:0000269|PubMed:1876184, ECO:0000269|PubMed:2247058, ECO:0000269|PubMed:27193682, ECO:0000269|PubMed:29158257, ECO:0000269|PubMed:3029109, ECO:0000269|PubMed:3818643, ECO:0000269|PubMed:7601352, ECO:0000269|PubMed:8413225, ECO:0000269|PubMed:8504927, ECO:0000269|PubMed:8515820, ECO:0000269|PubMed:8516311, ECO:0000269|PubMed:8516312, ECO:0000269|PubMed:8566795, ECO:0000269|PubMed:8662660}.

Subunit: (Microbial infection) Interacts with HIV-1 Vpr. {ECO:0000269|PubMed:8800208}.

Subunit: (Microbial infection) Interacts with Epstein-Barr virus EBNA2. {ECO:0000269|PubMed:7983760}.

Subunit: (Microbial infection) Interacts with Herpes simplex virus 1 protein ICP4. {ECO:0000269|PubMed:8392607}.

Subunit: (Microbial infection) Interacts (via C-terminus) with the Herpes simplex virus activator VP16; this interaction stimulates RNA Pol II transcription by increasing the extent of pre-initiation complex assembly. {ECO:0000269|PubMed:15654739, ECO:0000269|PubMed:8515819}.

Subcellular location: Nucleus {ECO:0000269|PubMed:12931194}. Chromosome {ECO:0000269|PubMed:24441171}. Note=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). {ECO:0000269|PubMed:24441171}.

Tissue specificity: Expressed in the inner cell mass forming the embryoblast (PubMed:24441171). Not detected in cells from the outer thin layer trophoblast (at protein level) (PubMed:24441171). {ECO:0000269|PubMed:24441171}.

Domain: The TFIIB-type zinc-binding domain is necessary for the interaction and recruitment of RNA polymerase II to the core promoter, the formation of a fully competent pre-initiation complex (PIC) assembly and basal transcription initiation (PubMed:8515820, PubMed:8516311, PubMed:8516312, PubMed:8413225). The C-terminus is necessary and sufficient for interaction with the TATA box-bound TBP complex and for the formation of PIC (PubMed:8515820, PubMed:8516311, PubMed:8413225). {ECO:0000269|PubMed:8413225, ECO:0000269|PubMed:8515820, ECO:0000269|PubMed:8516311, ECO:0000269|PubMed:8516312}.

Ptm: Acetylated (PubMed:24441171). Autoacetylated; autoacetylation at Lys-238 stimulates transcription activation (PubMed:12931194). {ECO:0000269|PubMed:12931194, ECO:0000269|PubMed:24441171}.

Similarity: Belongs to the TFIIB family. {ECO:0000305}.

Annotations taken from UniProtKB at the EBI.


Organism:		Homo sapiens (Human).
Taxonomy:		Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo.



Function:		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). {ECO:0000269\|PubMed:10318856, ECO:0000269\|PubMed:10619841, ECO:0000269\|PubMed:12931194, ECO:0000269\|PubMed:1517211, ECO:0000269\|PubMed:16230532, ECO:0000269\|PubMed:1876184, ECO:0000269\|PubMed:1946368, ECO:0000269\|PubMed:24441171, ECO:0000269\|PubMed:27193682, ECO:0000269\|PubMed:3029109, ECO:0000269\|PubMed:3818643, ECO:0000269\|PubMed:7601352, ECO:0000269\|PubMed:7675079, ECO:0000269\|PubMed:8413225, ECO:0000269\|PubMed:8504927, ECO:0000269\|PubMed:8515820, ECO:0000269\|PubMed:8516311, ECO:0000269\|PubMed:8516312, ECO:0000269\|PubMed:9420329}.


Catalytic activity:		Reaction=acetyl-CoA + L-lysyl-[protein] = CoA + H(+) + N(6)-acetyl-L- lysyl-[protein]; Xref=Rhea:RHEA:45948, Rhea:RHEA-COMP:9752, Rhea:RHEA-COMP:10731, ChEBI:CHEBI:15378, ChEBI:CHEBI:29969, ChEBI:CHEBI:57287, ChEBI:CHEBI:57288, ChEBI:CHEBI:61930; EC=2.3.1.48; Evidence={ECO:0000269\|PubMed:12931194};
Biophysicochemical properties:		Kinetic parameters: KM=0.117 mM for acetyl-CoA {ECO:0000269\|PubMed:12931194};
Subunit:		Found in a ternary complex with TATA box-bound TBP (PubMed:8413225, PubMed:8515820, PubMed:8516311, PubMed:8516312, PubMed:10619841, PubMed:29158257). 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, TAF7, TAF8, TAF9, TAF10, TAF11, TAF12 and TAF13 (PubMed:27193682). Associates with TFIID-TFIIA (DA complex) to form TFIID-TFIIA-TFIIB (DAB complex), which is then recognized by RNA polymerase II (Pol II) (PubMed:1876184, PubMed:2247058). Found in a RNA polymerase II initiation complex (PubMed:3818643, PubMed:3029109, PubMed:8413225, PubMed:8516312, PubMed:7601352). Interacts (via C- terminus) with TBP; this interaction with TATA box-bound TBP guides Pol II into the PIC (PubMed:8504927, PubMed:10619841). Interacts (via N- terminus) with Pol II (PubMed:8504927, PubMed:8413225). Interacts (via C-terminus) with SSU72; this interaction is inhibited by SYMPK (PubMed:29158257). Interacts with NR2F1; this interaction is direct (PubMed:1517211). Interacts with PGR (PubMed:1517211). Interacts with ESR1 (PubMed:1517211). Interacts with GTF2F1 (via C-terminus and preferentially via acetylated form); this interaction prevents binding of GTF2B to GTF2F2 (PubMed:8662660, PubMed:12931194). Interacts with GTF2F2 (via N-terminus); this interaction is inhibited in presence of GTF2F1 (PubMed:8504927, PubMed:8662660). Interacts with the transcription elongation factor TCEA2 (PubMed:8566795). Interacts with HSF1 (via transactivation domain) (PubMed:11005381). Interacts with GPBP1 (By similarity). {ECO:0000250\|UniProtKB:P62915, ECO:0000269\|PubMed:10619841, ECO:0000269\|PubMed:11005381, ECO:0000269\|PubMed:12931194, ECO:0000269\|PubMed:1517211, ECO:0000269\|PubMed:1876184, ECO:0000269\|PubMed:2247058, ECO:0000269\|PubMed:27193682, ECO:0000269\|PubMed:29158257, ECO:0000269\|PubMed:3029109, ECO:0000269\|PubMed:3818643, ECO:0000269\|PubMed:7601352, ECO:0000269\|PubMed:8413225, ECO:0000269\|PubMed:8504927, ECO:0000269\|PubMed:8515820, ECO:0000269\|PubMed:8516311, ECO:0000269\|PubMed:8516312, ECO:0000269\|PubMed:8566795, ECO:0000269\|PubMed:8662660}.
Subunit:		(Microbial infection) Interacts with HIV-1 Vpr. {ECO:0000269\|PubMed:8800208}.
Subunit:		(Microbial infection) Interacts with Epstein-Barr virus EBNA2. {ECO:0000269\|PubMed:7983760}.
Subunit:		(Microbial infection) Interacts with Herpes simplex virus 1 protein ICP4. {ECO:0000269\|PubMed:8392607}.
Subunit:		(Microbial infection) Interacts (via C-terminus) with the Herpes simplex virus activator VP16; this interaction stimulates RNA Pol II transcription by increasing the extent of pre-initiation complex assembly. {ECO:0000269\|PubMed:15654739, ECO:0000269\|PubMed:8515819}.
Subcellular location:		Nucleus {ECO:0000269\|PubMed:12931194}. Chromosome {ECO:0000269\|PubMed:24441171}. Note=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). {ECO:0000269\|PubMed:24441171}.
Tissue specificity:		Expressed in the inner cell mass forming the embryoblast (PubMed:24441171). Not detected in cells from the outer thin layer trophoblast (at protein level) (PubMed:24441171). {ECO:0000269\|PubMed:24441171}.
Domain:		The TFIIB-type zinc-binding domain is necessary for the interaction and recruitment of RNA polymerase II to the core promoter, the formation of a fully competent pre-initiation complex (PIC) assembly and basal transcription initiation (PubMed:8515820, PubMed:8516311, PubMed:8516312, PubMed:8413225). The C-terminus is necessary and sufficient for interaction with the TATA box-bound TBP complex and for the formation of PIC (PubMed:8515820, PubMed:8516311, PubMed:8413225). {ECO:0000269\|PubMed:8413225, ECO:0000269\|PubMed:8515820, ECO:0000269\|PubMed:8516311, ECO:0000269\|PubMed:8516312}.
Ptm:		Acetylated (PubMed:24441171). Autoacetylated; autoacetylation at Lys-238 stimulates transcription activation (PubMed:12931194). {ECO:0000269\|PubMed:12931194, ECO:0000269\|PubMed:24441171}.
Similarity:		Belongs to the TFIIB family. {ECO:0000305}.