title: Mitotic phosphorylation of the peripheral Golgi protein Nir2 by Cdk1 provides a docking mechanism for Plk1 and affects cytokinesis completion.
abstract: The rearrangement of the Golgi apparatus during mitosis is regulated by several protein kinases, including Cdk1 and Plk1. Several peripheral Golgi proteins that dissociate from the Golgi during mitosis are implicated in regulation of cytokinesis or chromosome segregation, thereby coordinating mitotic and cytokinetic events to Golgi rearrangement. Here we show that, at the onset of mitosis, Cdk1 phosphorylates the peripheral Golgi protein Nir2 at multiple sites; of these, S382 is the most prominent. Phosphorylation of Nir2 by Cdk1 facilitates its dissociation from the Golgi apparatus, and phospho-Nir2(pS382) is localized in the cleavage furrow and midbody during cytokinesis. Mitotic phosphorylation of Nir2 is required for docking of the phospho-Ser/Thr binding module, the Polo box domain of Plk1, and overexpression of a Nir2 mutant, which fails to interact with Plk1, affects the completion of cytokinesis. These results demonstrate a mechanism for coordinating mitotic and cytokinetic events with Golgi rearrangement during cell division.
authors.affiliation: Neurobiology Department and Mass Spectrometry Unit, Weizmann Institute of Science, Rehovot 76100, Israel.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Litvak
authors.forename: Rachel
authors.initials: R
authors.lastname: Argov
authors.forename: Nili
authors.initials: N
authors.lastname: Dahan
authors.forename: Sreekumar
authors.initials: S
authors.lastname: Ramachandran
authors.forename: Roy
authors.initials: R
authors.lastname: Amarilio
authors.forename: Alla
authors.initials: A
authors.lastname: Shainskaya
authors.forename: Sima
authors.initials: S
authors.lastname: Lev
mesh_terms: D016203:CDC2 Protein Kinase / Q000378:metabolism*; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D018797:Cell Cycle Proteins; D002455:Cell Division / Q000502:physiology; D005136:Eye Proteins / Q000378:metabolism*; D006056:Golgi Apparatus / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D008938:Mitosis / Q000502:physiology*; D009154:Mutation / Q000235:genetics; D010766:Phosphorylation; D011485:Protein Binding / Q000502:physiology; D011494:Protein Kinases / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases; D017434:Protein Structure, Tertiary / Q000502:physiology; D011518:Proto-Oncogene Proteins; D000097869:Polo-Like Kinase 1
chemical_list: D016203:CDC2 Protein Kinase; D002135:Calcium-Binding Proteins; D018797:Cell Cycle Proteins; D005136:Eye Proteins; D008565:Membrane Proteins; D011494:Protein Kinases; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D000097869:Polo-Like Kinase 1; C113505:PITPNM1 protein, human