title: Overexpression of a host factor TOM1 inhibits tomato mosaic virus propagation and suppression of RNA silencing.
abstract: A plant integral membrane protein TOM1 is involved in the multiplication of Tomato mosaic virus (ToMV). TOM1 interacts with ToMV replication proteins and has been suggested to tether the replication proteins to the membranes where the viral RNA synthesis takes place. We have previously demonstrated that inactivation of TOM1 results in reduced ToMV multiplication. In the present study, we show that overexpression of TOM1 in tobacco also inhibits ToMV propagation. TOM1 overexpression led to a decreased accumulation of the soluble form of the replication proteins and interfered with the ability of the replication protein to suppress RNA silencing. The reduced accumulation of the soluble replication proteins was also observed in a silencing suppressor-defective ToMV mutant. Based on these results, we propose that RNA silencing suppression is executed by the soluble form of the replication proteins and that efficient ToMV multiplication requires balanced accumulation of the soluble and membrane-bound replication proteins.
authors.affiliation: Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan.
authors.forename: Yuka
authors.initials: Y
authors.lastname: Hagiwara-Komoda
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Hirai
authors.forename: Atsuko
authors.initials: A
authors.lastname: Mochizuki
authors.forename: Masamichi
authors.initials: M
authors.lastname: Nishiguchi
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Meshi
authors.forename: Masayuki
authors.initials: M
authors.lastname: Ishikawa
mesh_terms: D000998:Antiviral Agents / Q000378:metabolism / Q000494:pharmacology; D018628:Gene Dosage; D010940:Plant Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000494:pharmacology; D014026:Nicotiana / Q000235:genetics / Q000821:virology*; D017898:Tobamovirus / Q000187:drug effects / Q000254:growth & development* / Q000502:physiology*; D014779:Virus Replication / Q000187:drug effects / Q000502:physiology
chemical_list: D000998:Antiviral Agents; D010940:Plant Proteins