Pseudouridylation of 7SK by PUS7 regulates Pol II transcription elongation
Creators
- 1. University of Chicago
Description
Pseudouridine (Ψ) is a widespread RNA modification in various RNA species, including rRNA, tRNA, snRNA and mRNA. Ψ plays a crucial role in RNA metabolism, where it regulates pre-mRNA splicing and affects protein translation. Whether and how Ψ may regulate transcription have not been adequately studied. Here, we report that pseudouridine synthase 7 (PUS7) can mediate pseudouridylation of 7SK small nuclear RNA (snRNA), a regulator of RNA polymerase II (Pol II) promoter-proximal pausing. PUS7 loss leads to hypo-pseudouridylation of 7SK, which promotes dissociation of the positive transcription elongation factor b (P-TEFb) complex from 7SK. The release of P-TEFb from 7SK increases serine 2 phosphorylation (Ser2P) in the RNA Pol II C-terminal domain and enhances transcription elongation. In colorectal cancer (CRC) cells, the Ψ level of 7SK can be modulated by PUS7, or by site-specifically targeted pseudouridylation through dCas13b-guided system. Hypo-pseudouridylation on 7SK upon PUS7 depletion promotes KLF6/DDIT3-mediated cell apoptosis and sensitizes CRC cells to 5-FU.
Data availability
The data supporting the findings of this study are available from the corresponding author upon request. The BID-seq, PAR-CLIP, KAS-seq and mRNA-seq data have been deposited at the Gene Expression Omnibus (GEO) under the accession number GEO: GSE288120. The processed data for BID-seq, PAR-CLIP, KAS-seq and mRNA-seq are provided in Supplementary Data 1–4. Details of the primers and siRNAs used in this study are also included in Supplementary Data 5. Source data are provided with this paper.Additional details
Identifiers
- DOI
- 10.1038/s41467-025-64668-5
- Other
- oai:uchicago.tind.io:16426
Funding
- National Institutes of Health
- R01HL155909
- National Institutes of Health
- RM1HG008935
- Unknown funder
- Josef Fried Chemical Biology Fellowship