title: Human NIMA-related kinase 6 is one of the Fe65 WW domain binding proteins.
abstract: The Aspergillus nidulans protein NIMA (never in mitosis, gene A) is a protein kinase required for initiation of mitosis, whereas its inactivation is necessary for mitotic exit. Here, we present evidence that human Nek6 is associated with Fe65. Based on the presence of Fe65 WW domain binding motifs ((267)PPLP(270)) in the Nek6 catalytic domain, we observed that Nek6 interacts physically with Fe65 both in vivo and in vitro, using a pull-down approach. Additionally, we detected co-localization of Nek6 and Fe65 via confocal microscopy. Co-localization of Nek6 and Fe65 was disrupted by mutation of the WW domain binding motifs ((267)PPLP(270)). Finally, when transient transfection assays were performed, interaction of Nek6 (wt) with Fe65 induced substantial cell apoptosis, whereas interaction using the Nek6 pplp mutant ((267)PPLP(270) changes (267)APVA(270)) did not. Thus, our observations indicated that Nek6 binds to Fe65 through its (267)PPLP(270) motif and that the protein-protein interaction between Nek6 and Fe65 regulates their subcellular localization and cell apoptosis.
authors.affiliation: School of Science Education, Chungbuk National University, Gaeshin-dong, Heungdok-gu, Chongju, Chungbuk 361-763, Republic of Korea.
authors.forename: Eun Jeoung
authors.initials: EJ
authors.lastname: Lee
authors.forename: Sung Hee
authors.initials: SH
authors.lastname: Hyun
authors.forename: Jaesun
authors.initials: J
authors.lastname: Chun
authors.forename: Sang Sun
authors.initials: SS
authors.lastname: Kang
mesh_terms: D000818:Animals; D017209:Apoptosis; D001233:Aspergillus nidulans / Q000378:metabolism*; D019556:COS Cells; D002453:Cell Cycle; D002522:Chlorocebus aethiops; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D008938:Mitosis; D016297:Mutagenesis, Site-Directed; D000072379:NIMA-Related Kinases; D009419:Nerve Tissue Proteins / Q000502:physiology*; D009687:Nuclear Proteins / Q000502:physiology*; D025941:Protein Interaction Mapping; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000502:physiology*; D017434:Protein Structure, Tertiary; D015398:Signal Transduction
chemical_list: C091042:APBB1 protein, human; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D049452:Green Fluorescent Proteins; D000072379:NIMA-Related Kinases; C442331:NIMA-related kinase 6; D017346:Protein Serine-Threonine Kinases