A Screen for Candidate Targets of Lysine Polyphosphorylation Uncovers a Conserved Network Implicated in Ribosome Biogenesis
Amanda Bentley-DeSousa,
Charlotte Holinier,
Houman Moteshareie,
Yi-Chieh Tseng,
Sam Kajjo,
Christine Nwosu,
Giuseppe Federico Amodeo,
Emma Bondy-Chorney,
Yuka Sai,
Adam Rudner,
Ashkan Golshani,
Norman E. Davey,
Michael Downey
Affiliations
Amanda Bentley-DeSousa
Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada; Ottawa Institute of Systems Biology, Ottawa, Ontario K1H 8M5, Canada
Charlotte Holinier
Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada; Ottawa Institute of Systems Biology, Ottawa, Ontario K1H 8M5, Canada
Houman Moteshareie
Department of Biology and Institute of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada; Ottawa Institute of Systems Biology, Ottawa, Ontario K1H 8M5, Canada
Yi-Chieh Tseng
Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada; Ottawa Institute of Systems Biology, Ottawa, Ontario K1H 8M5, Canada
Sam Kajjo
Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Ottawa Institute of Systems Biology, Ottawa, Ontario K1H 8M5, Canada
Christine Nwosu
Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada; Ottawa Institute of Systems Biology, Ottawa, Ontario K1H 8M5, Canada
Giuseppe Federico Amodeo
Department of Basic Sciences, New York University, College of Dentistry, 345 East 24th Street, New York, NY 10010, USA
Emma Bondy-Chorney
Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada; Ottawa Institute of Systems Biology, Ottawa, Ontario K1H 8M5, Canada
Yuka Sai
Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada; Ottawa Institute of Systems Biology, Ottawa, Ontario K1H 8M5, Canada
Adam Rudner
Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Ottawa Institute of Systems Biology, Ottawa, Ontario K1H 8M5, Canada
Ashkan Golshani
Department of Biology and Institute of Biochemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada; Ottawa Institute of Systems Biology, Ottawa, Ontario K1H 8M5, Canada
Norman E. Davey
Conway Institute of Biomolecular & Biomedical Research & UCD School of Medicine & Medical Science, University College Dublin, Belfield, Dublin 4, Ireland
Michael Downey
Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada; Ottawa Institute of Systems Biology, Ottawa, Ontario K1H 8M5, Canada; Corresponding author
Summary: Polyphosphates (polyP) are chains of inorganic phosphates found in all cells. Previous work has implicated these chains in diverse functions, but the mechanism of action is unclear. A recent study reports that polyP can be non-enzymatically and covalently attached to lysine residues on yeast proteins Nsr1 and Top1. One question emerging from this work is whether so-called “polyphosphorylation” is unique to these proteins or instead functions as a global regulator akin to other lysine post-translational modifications. Here, we present the results of a screen for polyphosphorylated proteins in yeast. We uncovered 15 targets including a conserved network of proteins functioning in ribosome biogenesis. Multiple genes contribute to polyphosphorylation of targets by regulating polyP synthesis, and disruption of this synthesis results in translation defects as measured by polysome profiling. Finally, we identify 6 human proteins that can be modified by polyP, highlighting the therapeutic potential of manipulating polyphosphorylation in vivo. : Bentley-DeSousa et al. screen yeast for proteins that undergo covalent modification by polyphosphate. They describe 15 substrates enriched for functions related to ribosome biogenesis. Homologs of these and other human proteins containing certain motifs can be “polyphosphorylated” using an ectopic expression system, providing a method to explore polyphosphorylation beyond yeast. Keywords: Vtc4, polyphosphate, lysine polyphosphorylation, ribosome biogenesis, Ppn1, Ppn2, yeast
