title: Interaction of tomato mosaic virus movement protein with tobacco RIO kinase.
abstract: Tomato mosaic virus (ToMV) has a regulatory gene encoding a movement protein (MP) that is involved in the cell-to-cell movement of viral RNA through plasmodesmata. To identify the host cell factors interacting with ToMV MP, we used a recombinant MP probe to isolate cDNA clones from a phage expression library of Nicotiana tabacum by a far-Western screening method. One of the cDNA clones encoded an MP-interacting protein, MIP-T7, homologous to the yeast novel protein kinase, Rio1p. We isolated a full-length cDNA by RT-PCR. The putative gene product was designated NtRIO, and shared 33 and 73% amino acid identity with yeast and Arabidopsis RIO kinases, respectively. In vitro analyses using recombinant proteins showed that NtRIO also interacted with a different MP derived from Cucumber mosaic virus. NtRIO had autophosphorylation activity and phosphorylated ToMV MP. Addition of recombinant tobacco casein kinase 2 resulted in a marked increase in the phosphorylation of NtRIO. The interaction between NtRIO and ToMV MP was inhibited by phosphorylation of NtRIO.
authors.affiliation: Gene Research Center, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Yoshioka
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Matsushita
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kasahara
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Konagaya
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nyunoya
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D017799:Cucumovirus / Q000235:genetics; D008969:Molecular Sequence Data; D010766:Phosphorylation; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D053830:Plant Viral Movement Proteins; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014026:Nicotiana / Q000201:enzymology* / Q000235:genetics; D014027:Tobacco Mosaic Virus / Q000378:metabolism*; D020798:Two-Hybrid System Techniques; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D010940:Plant Proteins; D053830:Plant Viral Movement Proteins; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D014764:Viral Proteins; D017346:Protein Serine-Threonine Kinases; C462948:Rio1 protein, S cerevisiae