RNA polymerase II stalling at pre-mRNA splice sites is enforced by ubiquitination of the catalytic subunit
- University of Edinburgh, United Kingdom
- Friedrich Miescher Institute for Biomedical Research, Switzerland
Abstract
Numerous links exist between co-transcriptional RNA processing and the transcribing RNAPII. In particular, pre-mRNA splicing was reported to be associated with slowed RNAPII elongation. Here we identify a site of ubiquitination (K1246) in the catalytic subunit of RNAPII close to the DNA entry path. Ubiquitination was increased in the absence of the Bre5-Ubp3 ubiquitin protease complex. Bre5 binds RNA in vivo, with a preference for exon 2 regions of intron-containing pre-mRNAs and poly(A) proximal sites. Ubiquitinated RNAPII showed similar enrichment. The absence of Bre5 led to impaired splicing and defects in RNAPII elongation in vivo on a splicing reporter construct. Strains expressing RNAPII with a K1246R mutation showed reduced cotranscriptional splicing. We propose that ubiquinitation of RNAPII is induced by RNA processing events and linked to transcriptional pausing, which is released by Bre5-Ubp3 associated with the nascent transcript.
Data availability
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RNA polymerase II stalling at pre-mRNA splice sites is enforced by ubiquitination of the catalytic subunitPublicly available at the NCBI Gene Expression Omnibus. Accession no:GSE94944, subseries GSE94942.
Article and author information
Author details
Funding
Wellcome (77248)
- David Tollervey
Medical Research Council
- Grzegorz Kudla
Wellcome (104648)
- Jean D Beggs
Wellcome (108504)
- Juri Rappsilber
Wellcome (93853)
- Jane E A Reid
Wellcome (97383)
- Grzegorz Kudla
Wellcome (92076)
- David Tollervey
Wellcome (200885)
- Robin Allshire
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Milligan 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 stalling at pre-mRNA splice sites is enforced by ubiquitination of the catalytic subunit
eLife 6:e27082.
https://doi.org/10.7554/eLife.27082
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