Disease relevance of TAF4

• The transactivation domain of adenovirus E1A interacts with the C terminus of human TAF(II)135 [1].
• By two-hybrid analysis with yeast and biochemical characterization of complexes formed by coexpression in Escherichia coli, we showed that hTAF(II)20 does not homodimerize but heterodimerizes with hTAF(II)135 [2].
• Coordinate regulation of RARgamma2, TBP, and TAFII135 by targeted proteolysis during retinoic acid-induced differentiation of F9 embryonal carcinoma cells [3].
• A library of phages containing cDNA-encoded peptides displayed on their surfaces is screened using as the target a specific region of one of the general transcription factors (e.g., the C terminus of hTAFII135) [4].

Psychiatry related information on TAF4

• Sp1 and TAFII130 transcriptional activity disrupted in early Huntington's disease [5].

High impact information on TAF4

• We found that expanded polyQ stretches preferentially bind to TAFII130, a coactivator involved in cAMP-responsive element binding protein (CREB)-dependent transcriptional activation, and strongly suppress CREB-dependent transcriptional activation [6].
• Expanded polyglutamine stretches interact with TAFII130, interfering with CREB-dependent transcription [6].
• The suppression of CREB-dependent transcription and the cell death induced by polyQ stretches were restored by the co-expression of TAFII130 [6].
• 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 [7].
• We report for the first time the cloning of a complete cDNA encoding the human TFIID subunit hTAF(II)135 (hTAF(II)130) [8].

Biological context of TAF4

• We also show that the TAF12-dependent transcriptional activation is competitively inhibited by TAF4 [9].
• Here, we demonstrate that CR3 can complex with the extreme C-terminal 105 amino acids of the human TATA box binding-factor-associated protein, hTAF(II)135 [1].
• Interaction with hTAF(II)20 requires a domain of hTAF(II)135 which shows sequence homology to H2A [2].
• Correspondingly, overexpression of hTAFII130 potentiated CREB activity in cells exposed to cAMP, but had no effect on reporter gene expression in unstimulated cells [10].
• CONCLUSIONS: These observations indicate that appropriately timed proteolysis of TBP and TAFII135 is required for normal F9 cell differentiation [3].

Anatomical context of TAF4

• Moreover, ectopic expression of TAFII135 delays proteolysis of the RARgamma2 receptor and impairs primitive endoderm differentiation at an early stage as evidenced by cell morphology, induction of marker genes and apoptotic response [3].
• The activation domain of the enhancer binding protein p45NF-E2 interacts with TAFII130 and mediates long-range activation of the alpha- and beta-globin gene loci in an erythroid cell line [11].

Associations of TAF4 with chemical compounds

• Human TAF(II)135 potentiates transcriptional activation by the AF-2s of the retinoic acid, vitamin D3, and thyroid hormone receptors in mammalian cells [8].

Regulatory relationships of TAF4

• These results suggest a dynamic TFIID structure in which the switch from a basal hTAF(II)-enhanced repression state to an activator-mediated activated state on a promoter may be mediated in part through activator or coactivator interactions with hTAF(II)135 [12].

Other interactions of TAF4

• To elucidate the structural organization and function of TFIID, we expressed and characterized the product of a cloned cDNA encoding human TAF(II)135 (hTAF(II)135) [12].
• Comparative far Western blots have shown that hTAF(II)135 interacts strongly with hTAF(II)20, moderately with hTAF(II)150, and weakly with hTAF(II)43 and hTAF(II)250 [12].
• This indicates that either full-length TAF4 contains an unusually long connecting loop between its second and third helix, and this helix is not required for stable interaction with TAF12, or that TAF4 represents a novel class of partial histone fold motifs [13].
• Molecular cloning and analysis of two subunits of the human TFIID complex: hTAFII130 and hTAFII100 [14].
• The central domain of hTAFII130 contains four glutamine-rich regions, designated Q1 to Q4, that are involved in interactions with the transcriptional activator Sp1 [15].

References