RNA Polymerase II transcription independent of TBP
- University of British Columbia, Canada
Abstract
Transcription by RNA Polymerase II (Pol II) is initiated by the hierarchical assembly of the Pre-Initiation Complex onto promoter DNA. Decades of research have shown that the TATA-box binding protein (TBP) is essential for Pol II loading and initiation. Here, we report instead that acute depletion of TBP in mouse embryonic stem cells has no global effect on ongoing Pol II transcription. In contrast, acute TBP depletion severely impairs RNA Polymerase III initiation. Furthermore, Pol II transcriptional induction occurs normally upon TBP depletion. This TBP-independent transcription mechanism is not due to a functional redundancy with the TBP paralog TRF2, though TRF2 also binds to promoters of transcribed genes. Rather, we show that the TFIID complex can form and, despite having reduced TAF4 and TFIIA binding when TBP is depleted, the Pol II machinery is sufficiently robust in sustaining TBP-independent transcription.
Data availability
All sequencing data have been deposited in Gene Expression Omnibus (Accession number GSE172401). All mass spectrometry data have been deposited to ProteomeExchange (PXD034171) through MassIVE (MSV000089562). All other data are available in the manuscript or in the supplementary materials.
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RNA Polymerase II transcription independent of TBPNCBI Gene Expression Omnibus, GSE172401.
Article and author information
Author details
Funding
Canadian Institutes of Health Research (PJT-162289)
- Filip Van Petegem
Natural Sciences and Engineering Research Council of Canada (RGPIN-2020-06106)
- Sheila S Teves
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Kwan et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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RNA Polymerase II transcription independent of TBP
eLife 12:e83810.
https://doi.org/10.7554/eLife.83810
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