title: Mitotic phosphotyrosine network analysis reveals that tyrosine phosphorylation regulates Polo-like kinase 1 (PLK1).
abstract: Tyrosine phosphorylation is closely associated with cell proliferation. During the cell cycle, serine and threonine phosphorylation plays the leading role, and such phosphorylation events are most dynamic during the mitotic phase of the cell cycle. However, mitotic phosphotyrosine is not well characterized. Although a few functionally-relevant mitotic phosphotyrosine sites have been characterized, evidence suggests that this modification may be more prevalent than previously appreciated. Here, we examined tyrosine phosphorylation in mitotic human cells including those on spindle-associated proteins.? Database mining confirmed ~2000 mitotic phosphotyrosine sites, and network analysis revealed a number of subnetworks that were enriched in tyrosine-phosphorylated proteins, including components of the kinetochore or spindle and SRC family kinases. We identified Polo-like kinase 1 (PLK1), a major signaling hub in the spindle subnetwork, as phosphorylated at the conserved Tyr217in the kinase domain. Substitution of Tyr217with a phosphomimetic residue eliminated PLK1 activity in vitro and in cells. Further analysis showed that Tyr217phosphorylation reduced the phosphorylation of Thr210in the activation loop, a phosphorylation event necessary for PLK1 activity. Our data indicate that mitotic tyrosine phosphorylation regulated a key serine/threonine kinase hub in mitotic cells and suggested that spatially separating tyrosine phosphorylation events can reveal previously unrecognized regulatory events and complexes associated with specific structures of the cell cycle.
authors.affiliation: Department of Pediatrics, Faculty of Medicine, Université Laval, Centre Hospitalier Universitaire de Québec Research Center, Quebec City, Quebec G1V 4G2, Canada.
authors.forename: Danielle
authors.initials: D
authors.lastname: Caron
authors.affiliation: Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, U.K.
authors.forename: Dominic P
authors.initials: DP
authors.lastname: Byrne
authors.affiliation: Department of Pediatrics, Faculty of Medicine, Université Laval, Centre Hospitalier Universitaire de Québec Research Center, Quebec City, Quebec G1V 4G2, Canada.
authors.forename: Philippe
authors.initials: P
authors.lastname: Thebault
authors.affiliation: Department of Psychiatry et Neurosciences, Faculty of Medicine, Université Laval, Centre Hospitalier Universitaire de Québec Research Center, Quebec City, Quebec G1V 4G2, Canada.
authors.forename: Denis
authors.initials: D
authors.lastname: Soulet
authors.affiliation: Institut de Biologie Intégrative et des Systèmes, Department of Biology, PROTEO, Université Laval, Pavillon Charles-Eugène-Marchand, 1030 Avenue de la Médecine, Quebec City, Quebec G1V 0A6, Canada.
authors.forename: Christian R
authors.initials: CR
authors.lastname: Landry
authors.affiliation: Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, U.K.
authors.forename: Patrick A
authors.initials: PA
authors.lastname: Eyers
authors.affiliation: Department of Pediatrics, Faculty of Medicine, Université Laval, Centre Hospitalier Universitaire de Québec Research Center, Quebec City, Quebec G1V 4G2, Canada. sabine.elowe@crchudequebec.ulaval.ca.
authors.forename: Sabine
authors.initials: S
authors.lastname: Elowe
mesh_terms: D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D006801:Humans; D008938:Mitosis / Q000502:physiology*; D010766:Phosphorylation / Q000502:physiology; D000072417:Protein Domains; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D008941:Spindle Apparatus / Q000201:enzymology* / Q000235:genetics; D014443:Tyrosine / Q000235:genetics / Q000378:metabolism; D000097869:Polo-Like Kinase 1
chemical_list: D018797:Cell Cycle Proteins; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D014443:Tyrosine; D000097869:Polo-Like Kinase 1