Human TAFII 105 is a cell type-specific TFIID subunit related to hTAFII130.
We previously characterized Drosophila and human TAF subunits that make up the core TFIID complex found in all cells. Here, we report that differentiated B cells contain a novel substoichiometric TAF of 105 kDa not found associated with TFIID isolated from other cell types. The cDNA encoding hTAFII105 reveals a highly conserved C-terminal domain shared by hTAFII130 and oTAFII110, while the N-terminal coactivator domain has diverged significantly. All cells tested express TAFII105 mRNA, but only B cells contain significant levels of protein associated with TFIID. Transient overexpression of hTAFII105 selectively squelches the transcription of some genes in B cells. These properties suggest that TAFII105 is a cell type-specific subunit of TFIID that may be responsible for mediating transcription by a subset of activators in B cells.
Dikstein
R
R
Howard Hughes Medical Institute, Department of Molecular and Cell Biology, University of California, Berkeley 94720-3204, USA.
Zhou
S
S
Tjian
R
R
D000595:Amino Acid Sequence; D000818:Animals; D001402:B-Lymphocytes / Q000737:chemistry* / Q000166:cytology; D002454:Cell Differentiation; D002460:Cell Line; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004268:DNA-Binding Proteins / Q000032:analysis* / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D004330:Drosophila; D029721:Drosophila Proteins; D015870:Gene Expression; D006801:Humans; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D011993:Recombinant Fusion Proteins; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D035381:TATA-Binding Protein Associated Factors; D015534:Trans-Activators / Q000235:genetics; D035362:Transcription Factor TFIID; D014157:Transcription Factors / Q000032:analysis* / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism
D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; C486319:TAF1C protein, human; C101882:TAF4 protein, human; C101881:TAF4B protein, human; D035381:TATA-Binding Protein Associated Factors; C103338:Taf4 protein, Drosophila; D015534:Trans-Activators; D035362:Transcription Factor TFIID; D014157:Transcription Factors