WDR82/PNUTS-PP1 Prevents Transcription-Replication Conflicts by Promoting RNA Polymerase II Degradation on Chromatin
Helga B. Landsverk,
Lise E. Sandquist,
Lilli T.E. Bay,
Barbara Steurer,
Coen Campsteijn,
Ole J.B. Landsverk,
Jurgen A. Marteijn,
Eva Petermann,
Laura Trinkle-Mulcahy,
Randi G. Syljuåsen
Affiliations
Helga B. Landsverk
Department of Radiation Biology, Institute for Cancer Research, Norwegian Radium Hospital, Oslo University Hospital, 0379 Oslo, Norway; Corresponding author
Lise E. Sandquist
Department of Radiation Biology, Institute for Cancer Research, Norwegian Radium Hospital, Oslo University Hospital, 0379 Oslo, Norway
Lilli T.E. Bay
Department of Radiation Biology, Institute for Cancer Research, Norwegian Radium Hospital, Oslo University Hospital, 0379 Oslo, Norway
Barbara Steurer
Department of Molecular Genetics, Oncode Institute, Erasmus MC, University Medical Center Rotterdam, 3015 GE Rotterdam, the Netherlands
Coen Campsteijn
Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, 0372 Oslo, Norway
Ole J.B. Landsverk
Department of Pathology, Oslo University Hospital, 0372 Oslo, Norway
Jurgen A. Marteijn
Department of Molecular Genetics, Oncode Institute, Erasmus MC, University Medical Center Rotterdam, 3015 GE Rotterdam, the Netherlands
Eva Petermann
Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
Laura Trinkle-Mulcahy
Department of Cellular and Molecular Medicine and Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, ON K1H 8M5, Canada
Randi G. Syljuåsen
Department of Radiation Biology, Institute for Cancer Research, Norwegian Radium Hospital, Oslo University Hospital, 0379 Oslo, Norway; Corresponding author
Summary: Transcription-replication (T-R) conflicts cause replication stress and loss of genome integrity. However, the transcription-related processes that restrain such conflicts are poorly understood. Here, we demonstrate that the RNA polymerase II (RNAPII) C-terminal domain (CTD) phosphatase protein phosphatase 1 (PP1) nuclear targeting subunit (PNUTS)-PP1 inhibits replication stress. Depletion of PNUTS causes lower EdU uptake, S phase accumulation, and slower replication fork rates. In addition, the PNUTS binding partner WDR82 also promotes RNAPII-CTD dephosphorylation and suppresses replication stress. RNAPII has a longer residence time on chromatin after depletion of PNUTS or WDR82. Furthermore, the RNAPII residence time is greatly enhanced by proteasome inhibition in control cells but less so in PNUTS- or WDR82-depleted cells, indicating that PNUTS and WDR82 promote degradation of RNAPII on chromatin. Notably, reduced replication is dependent on transcription and the phospho-CTD binding protein CDC73 after depletion of PNUTS/WDR82. Altogether, our results suggest that RNAPII-CTD dephosphorylation is required for the continuous turnover of RNAPII on chromatin, thereby preventing T-R conflicts.
