title: Identification of an amino acid residue required for differential recognition of a viral movement protein by the Tomato mosaic virus resistance gene Tm-2(2).
abstract: The Tm-2 gene of tomato and its allelic gene, Tm-2(2), confer resistance to Tomato mosaic virus (ToMV) and encode a member of the coiled-coil/nucleotide binding-ARC/leucine-rich repeat (LRR) protein class of plant resistance (R) genes. Despite exhibiting only four amino acid differences between the products of Tm-2 and Tm-2(2), Tm-2(2) confers resistance to ToMV mutant B7, whereas Tm-2 is broken by ToMV-B7. An Agrobacterium-mediated transient expression system was used to study the mechanism of differential recognition of the movement proteins (MPs), an avirulence factor for ToMV resistance, of ToMV-B7 by Tm-2 and Tm-2(2). Although resistance induced by Tm-2 and Tm-2(2) is not usually accompanied by hypersensitive response (HR), Tm-2 and Tm-2(2) induced HR-like cell death by co-expression with MP of a wild-type ToMV, a strain that causes resistance for these R genes, and Tm-2(2) but not Tm-2 induced cell death with B7-MP in this system. Site-directed amino acid mutagenesis revealed that Tyr-767 in the LRR of Tm-2(2) is required for the specific recognition of the B7-MP. These results suggest that the Tyr residue in LRR contributes to the recognition of B7-MP, and that Tm-2 and Tm-2(2) are involved in HR cell death.
authors.affiliation: National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602, Japan.
authors.forename: Michie
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Ayako
authors.initials: A
authors.lastname: Yamamoto-Katou
authors.forename: Shinpei
authors.initials: S
authors.lastname: Katou
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Hirai
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Meshi
authors.forename: Yuko
authors.initials: Y
authors.lastname: Ohashi
authors.forename: Ichiro
authors.initials: I
authors.lastname: Mitsuhara
mesh_terms: D000483:Alleles; D019943:Amino Acid Substitution; D002352:Carrier Proteins / Q000235:genetics*; D016923:Cell Death; D004252:DNA Mutational Analysis; D018076:DNA, Complementary / Q000235:genetics; D017343:Genes, Plant / Q000235:genetics; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D018551:Solanum lycopersicum / Q000235:genetics*; D016297:Mutagenesis, Site-Directed; D009842:Oligopeptides; D010446:Peptide Fragments; D010455:Peptides; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D053830:Plant Viral Movement Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism / Q000821:virology; D018749:RNA, Plant / Q000235:genetics; D011993:Recombinant Fusion Proteins; D014026:Nicotiana / Q000235:genetics* / Q000378:metabolism / Q000821:virology*; D017898:Tobamovirus / Q000235:genetics / Q000378:metabolism*; D014343:Trypan Blue
chemical_list: D002352:Carrier Proteins; D018076:DNA, Complementary; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D009842:Oligopeptides; D010446:Peptide Fragments; D010455:Peptides; D010940:Plant Proteins; D053830:Plant Viral Movement Proteins; D018749:RNA, Plant; D011993:Recombinant Fusion Proteins; C475510:tyrosyl-prolyl-tyrosyl-aspartyl-valyl-prolyl-aspartyl-tyrosyl-alanine; C085706:FLAG peptide; D014343:Trypan Blue