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bioRxiv · 10.1101/184317

Downstream promoter interactions of TFIID TAFs facilitate transcription reinitiation

Joo, Y. J.·Ficarro, S. B.·Soares, L. M.·Chun, Y.·Marto, J. A.·Buratowski, S.
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Abstract

TFIID binds promoter DNA to recruit RNA polymerase II and other basal factors for transcription. Although the TATA-Binding Protein (TBP) subunit of TFIID is necessary and sufficient for in vitro transcription, the TBP-Associated Factor (TAF) subunits recognize downstream promoter elements, act as co-activators, and interact with nucleosomes. Here we show that transcription induces stable TAF binding to downstream promoter DNA, independent of upstream contacts, TBP, or other basal transcription factors. This transcription-dependent TAF complex promotes subsequent activator-independent transcription, and promoter response to TAF mutations in vivo correlates with the level of downstream, rather than overall, Taf1 crosslinking. We propose a new model in which TAFs function as reinitiation factors, accounting for the differential responses of promoters to various transcription factor mutations.

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Joo, Y. J., Ficarro, S. B., Soares, L. M., Chun, Y., Marto, J. A., Buratowski, S.. 2017-09-04. Downstream promoter interactions of TFIID TAFs facilitate transcription reinitiation. https://doi.org/10.1101/184317

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