title: A role for Plk1 phosphorylation of NudC in cytokinesis.
abstract: Polo-like kinase 1 (Plk1) plays essential roles at multiple events during cell division, yet little is known about its physiological substrates. In a cDNA phage display screen using Plk1 C-terminal affinity columns, we identified NudC (nuclear distribution gene C) as a Plk1 binding protein. Here, we characterize the interaction between Plk1 and NudC, show that Plk1 phosphorylates NudC at conserved S274 and S326 residues in vitro, and present evidence that NudC is also a substrate for Plk1 in vivo. Downregulation of NudC by RNA interference results in multiple mitotic defects, including multinucleation and cells arrested at the midbody stage, which are rescued by ectopic expression of wild-type NudC, but not by NudC with mutations in the Plk1 phosphorylation sites. These results suggest that Plk1 phosphorylation of NudC may influence cytokinesis.
authors.affiliation: Department of Molecular and Cellular Biology, Harvard University, 16 Divinity Avenue, Cambridge, MA 02138, USA. tzhou@mcb.harvard.edu
authors.forename: Tianhua
authors.initials: T
authors.lastname: Zhou
authors.forename: Jonathan P
authors.initials: JP
authors.lastname: Aumais
authors.forename: Xiaoqi
authors.initials: X
authors.lastname: Liu
authors.forename: Li-Yuan
authors.initials: LY
authors.lastname: Yu-Lee
authors.forename: Raymond L
authors.initials: RL
authors.lastname: Erikson
mesh_terms: D000818:Animals; D019556:COS Cells; D018797:Cell Cycle Proteins; D002455:Cell Division / Q000502:physiology*; D002522:Chlorocebus aethiops; D005786:Gene Expression Regulation; D005982:Glutathione Transferase / Q000378:metabolism; D049452:Green Fluorescent Proteins; D006367:HeLa Cells; D006801:Humans; D008164:Luminescent Proteins / Q000378:metabolism; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009687:Nuclear Proteins; D010766:Phosphorylation; D017354:Point Mutation; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D017346:Protein Serine-Threonine Kinases; D011506:Proteins / Q000378:metabolism*; D011518:Proto-Oncogene Proteins; D034741:RNA, Small Interfering / Q000378:metabolism; D000097869:Polo-Like Kinase 1
chemical_list: D018797:Cell Cycle Proteins; D005982:Glutathione Transferase; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins; D009687:Nuclear Proteins; D011494:Protein Kinases; D017346:Protein Serine-Threonine Kinases; D011506:Proteins; D011518:Proto-Oncogene Proteins; D034741:RNA, Small Interfering; D000097869:Polo-Like Kinase 1; C512648:NUDC protein, human