Characterization of a novel serine/threonine kinase associated with nuclear bodies.
A novel protein kinase, Mx-interacting protein kinase (PKM), has been identified in a yeast two-hybrid screen for interaction partners of human MxA, an interferon-induced GTPase with antiviral activity against several RNA viruses. A highly conserved protein kinase domain is present in the N-terminal moiety of PKM, whereas an Mx interaction domain overlaps with C-terminal PEST sequences. PKM has a molecular weight of about 127,000 and exhibits high sequence homology to members of a recently described family of homeodomain-interacting protein kinases. Recombinant PKM has serine/threonine kinase activity that is abolished by a single amino acid substitution in the ATP binding domain (K221W). PKM catalyzes autophosphorylation and phosphorylation of various cellular and viral proteins. PKM is expressed constitutively and colocalizes with the interferon-inducible Sp100 protein and murine Mx1 in discrete nuclear structures known as nuclear bodies.
Trost
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Abteilung Virologie, Institut für Medizinische Mikrobiologie und Hygiene, Universität Freiburg, D-79008 Freiburg, Germany.
Kochs
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Haller
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D000595:Amino Acid Sequence; D000998:Antiviral Agents / Q000032:analysis*; D002467:Cell Nucleus / Q000737:chemistry*; D019204:GTP-Binding Proteins; D006801:Humans; D008969:Molecular Sequence Data; D008970:Molecular Weight; D064547:Myxovirus Resistance Proteins; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000032:analysis* / Q000737:chemistry / Q000235:genetics; D011506:Proteins / Q000032:analysis*
D000998:Antiviral Agents; C579071:MX1 protein, human; D064547:Myxovirus Resistance Proteins; D011506:Proteins; D017346:Protein Serine-Threonine Kinases; D019204:GTP-Binding Proteins