title: The spread of Rice dwarf virus among cells of its insect vector exploits virus-induced tubular structures.
abstract: Various cytopathological structures, known as inclusion bodies, are formed upon infection of cultured leafhopper cells by Rice dwarf virus, a member of the family Reoviridae. These structures include tubules of approximately 85 nm in diameter which are composed of the nonstructural viral protein Pns10 and contain viral particles. Such tubular structures were produced in heterologous non-host insect cells that expressed Pns10 of the virus. These tubules, when associated with actin-based filopodia, were able to protrude from the surface of cells and to penetrate neighboring cells. A binding assay in vitro revealed the specific binding of Pns10 to actin. Infection of clusters of cells was readily apparent 5 days after inoculation at a low multiplicity of infection with the virus, even in the presence of neutralizing antibodies. However, treatment of host cells with drugs that inhibited the elongation of actin filaments abolished the extension of Pns10 tubules from the surface of cells, with a significant simultaneous decrease in the extent of infection of neighboring cells. These results together revealed a previously undescribed aspect of the intercellular spread of Rice dwarf virus, wherein the virus exploits tubules composed of a nonstructural viral protein and actin-based filopodia to move into neighboring cells.
authors.affiliation: Laboratory of Virology, National Agricultural Research Center, Tsukuba, Ibaraki, Japan.
authors.forename: Taiyun
authors.initials: T
authors.lastname: Wei
authors.forename: Akira
authors.initials: A
authors.lastname: Kikuchi
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Moriyasu
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Suzuki
authors.forename: Takumi
authors.initials: T
authors.lastname: Shimizu
authors.forename: Kyoji
authors.initials: K
authors.lastname: Hagiwara
authors.forename: Hongyan
authors.initials: H
authors.lastname: Chen
authors.forename: Mami
authors.initials: M
authors.lastname: Takahashi
authors.forename: Tamaki
authors.initials: T
authors.lastname: Ichiki-Uehara
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Omura
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D002478:Cells, Cultured; D006430:Hemiptera / Q000648:ultrastructure / Q000821:virology*; D002479:Inclusion Bodies / Q000648:ultrastructure / Q000821:virology; D007303:Insect Vectors / Q000648:ultrastructure / Q000821:virology*; D008854:Microscopy, Electron; D008870:Microtubules / Q000648:ultrastructure / Q000821:virology*; D012275:Oryza / Q000821:virology*; D012087:Reoviridae / Q000502:physiology*; D018411:Spodoptera; D017361:Viral Nonstructural Proteins / Q000378:metabolism*
chemical_list: D000199:Actins; D017361:Viral Nonstructural Proteins