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PubMed · 15601843

Core promoter binding by histone-like TAF complexes.

Hanshuang Shao·Merav Revach·Sandra Moshonov·Yael Tzuman·Kfir Gazit·Shira Albeck·Tamar Unger·Rivka Dikstein
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Abstract

A major function of TFIID is core promoter recognition. TFIID consists of TATA-binding protein (TBP) and 14 TBP-associated factors (TAFs). Most of them contain a histone fold domain (HFD) that lacks the DNA-contacting residues of histones. Whether and how TAF HFDs contribute to core promoter DNA binding are yet unresolved. Here we examined the DNA binding activity of TAF9, TAF6, TAF4b, and TAF12, which are related to histones H3, H4, H2A, and H2B, respectively. Each of these TAFs has intrinsic DNA binding activity adjacent to or within the HFD. The DNA binding domains were mapped to evolutionarily conserved and essential regions. Remarkably, HFD-mediated interaction enhanced the DNA binding activity of each of the TAF6-TAF9 and TAF4b-TAF12 pairs and of a histone-like octamer complex composed of the four TAFs. Furthermore, HFD-mediated interaction stimulated sequence-specific binding by TAF6 and TAF9. These results suggest that TAF HFDs merge with other conserved domains for efficient and specific core promoter binding.

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Amino Acid MotifsAnimalsBase SequenceBinding, CompetitiveDNAElectrophoresis, Polyacrylamide GelEvolution, MolecularGenetic Complementation TestGlutathione TransferaseHistonesHumansImmunoprecipitationModels, GeneticMolecular Sequence DataPromoter Regions, GeneticProtein BindingProtein ConformationProtein FoldingProtein Structure, TertiaryRNATATA-Binding Protein Associated FactorsTemperatureTranscription Factor TFIIDTranscription FactorsUltraviolet RaysJournal ArticleResearch Support, Non-U.S. Gov't

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Hanshuang Shao, Merav Revach, Sandra Moshonov, Yael Tzuman, Kfir Gazit, Shira Albeck, Tamar Unger, Rivka Dikstein. 2005. Core promoter binding by histone-like TAF complexes.. https://doi.org/10.1128/mcb.25.1.206-219.2005

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