title: Arabidopsis TOBAMOVIRUS MULTIPLICATION (TOM) 2 locus encodes a transmembrane protein that interacts with TOM1.
abstract: The tom2-1 mutation of Arabidopsis thaliana reduces the efficiency of intracellular multiplication of tobamoviruses. The tom2-1 mutant was derived from fast-neutron-irradiated seeds, and the original mutant line also carries ttm1, a dominant modifier that increases tobamovirus multiplication efficiency in a tobamovirus-strain-specific manner in the tom2-1 genetic background. Here, we show that the tom2-1 mutation involved a deletion of approximately 20 kb in the nuclear genome. The deleted region included two genes named TOM2A and TOM2B that were both associated with the tom2-1 phenotype, whereas ttm1 corresponded to the translocation of part of the deleted region that included intact TOM2B but not TOM2A. TOM2A encodes a 280 amino acid putative four-pass transmembrane protein with a C-terminal farnesylation signal, while TOM2B encodes a 122 amino acid basic protein. The split-ubiquitin assay demonstrated an interaction of TOM2A both with itself and with TOM1, an integral membrane protein of A.thaliana presumed to be an essential constituent of tobamovirus replication complex. The data presented here suggest that TOM2A is also an integral part of the tobamovirus replication complex.
authors.affiliation: Division of Applied Bioscience, Graduate School of Agriculture, Hokkaido University, Sapporo 060-8589 and CREST, Japan.
authors.forename: Yayoi
authors.initials: Y
authors.lastname: Tsujimoto
authors.forename: Takuro
authors.initials: T
authors.lastname: Numaga
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Ohshima
authors.forename: Masa-Aki
authors.initials: MA
authors.lastname: Yano
authors.forename: Ryuji
authors.initials: R
authors.lastname: Ohsawa
authors.forename: Derek B
authors.initials: DB
authors.lastname: Goto
authors.forename: Satoshi
authors.initials: S
authors.lastname: Naito
authors.forename: Masayuki
authors.initials: M
authors.lastname: Ishikawa
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism / Q000821:virology; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D017343:Genes, Plant; D005816:Genetic Complementation Test; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D016366:Open Reading Frames; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012639:Seeds / Q000737:chemistry / Q000528:radiation effects; D017898:Tobamovirus / Q000502:physiology*; D025801:Ubiquitin / Q000378:metabolism; D014764:Viral Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D002352:Carrier Proteins; D008565:Membrane Proteins; D011993:Recombinant Fusion Proteins; C413802:TOM1 protein, Arabidopsis; C471269:TOM2 protein, Arabidopsis; D025801:Ubiquitin; D014764:Viral Proteins