title: PLK1 phosphorylation of pericentrin initiates centrosome maturation at the onset of mitosis.
abstract: The microtubule-organizing activity of the centrosome oscillates during the cell cycle, reaching its highest level at mitosis. At the onset of mitosis, the centrosome undergoes maturation, which is characterized by a drastic expansion of the pericentriolar matrix (PCM) and a robust increase in microtubule-organizing activity. It is known that PLK1 is critical for the initiation of centrosome maturation. In this paper, we report that pericentrin (PCNT), a PCM protein, was specifically phosphorylated by PLK1 during mitosis. Phosphoresistant point mutants of PCNT did not recruit centrosomal proteins, such as CEP192, GCP-WD (γ-complex protein with WD repeats), γ-tubulin, Aurora A, and PLK1, into the centrosome during mitosis. However, centrosomal recruitment of CEP215 depended on PCNT irrespective of its phosphorylation status. Furthermore, ectopic expression of PLK1-PCNT fusion proteins induced the centrosomal accumulation of CEP192, GCP-WD, and γ-tubulin even in interphase cells, mimicking centrosome maturation. Based on these results, we propose that PLK1-mediated phosphorylation of PCNT initiates centrosome maturation by organizing the spindle pole-specific PCM lattice.
authors.affiliation: Department of Biological Sciences, Seoul National University, Seoul 151-747, South Korea.
authors.forename: Kwanwoo
authors.initials: K
authors.lastname: Lee
authors.forename: Kunsoo
authors.initials: K
authors.lastname: Rhee
mesh_terms: D000941:Antigens / Q000737:chemistry / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000378:metabolism*; D002478:Cells, Cultured; D018385:Centrosome / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D007399:Interphase; D008870:Microtubules / Q000378:metabolism; D008938:Mitosis; D008954:Models, Biological; D010766:Phosphorylation; D020033:Protein Isoforms / Q000737:chemistry / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D008941:Spindle Apparatus / Q000378:metabolism; D000097869:Polo-Like Kinase 1
chemical_list: D000941:Antigens; D018797:Cell Cycle Proteins; D020033:Protein Isoforms; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D011993:Recombinant Fusion Proteins; D000097869:Polo-Like Kinase 1; C086178:pericentrin