title: Nucleocapsid of Tomato spotted wilt tospovirus forms mobile particles that traffic on an actin/endoplasmic reticulum network driven by myosin XI-K.
abstract: A number of viral proteins from plant viruses, other than movement proteins, have been shown to traffic intracellularly along actin filaments and to be involved in viral infection. However, there has been no report that a viral capsid protein may traffic within a cell by utilizing the actin/endoplasmic reticulum (ER) network. We used Tomato spotted wilt tospovirus (TSWV) as a model virus to study the cell biological properties of a nucleocapsid (N) protein. We found that TSWV N protein was capable of forming highly motile cytoplasmic inclusions that moved along the ER and actin network. The disruption of actin filaments by latrunculin B, an actin-depolymerizing agent, almost stopped the intracellular movement of N inclusions, whereas treatment with a microtubule-depolymerizing reagent, oryzalin, did not. The over-expression of a myosin XI-K tail, functioning in a dominant-negative manner, completely halted the movement of N inclusions. Latrunculin B treatment strongly inhibited the formation of TSWV local lesions in Nicotiana tabacum cv Samsun NN and delayed systemic infection in N. benthamiana. Collectively, our findings provide the first evidence that the capsid protein of a plant virus has the novel property of intracellular trafficking. The findings add capsid protein as a new class of viral protein that traffics on the actin/ER system.
authors.affiliation: Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Department of Plant Pathology, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Zhike
authors.initials: Z
authors.lastname: Feng
authors.forename: Xiaojiao
authors.initials: X
authors.lastname: Chen
authors.forename: Yiqun
authors.initials: Y
authors.lastname: Bao
authors.forename: Jiahong
authors.initials: J
authors.lastname: Dong
authors.forename: Zhongkai
authors.initials: Z
authors.lastname: Zhang
authors.forename: Xiaorong
authors.initials: X
authors.lastname: Tao
mesh_terms: D008841:Actin Cytoskeleton / Q000187:drug effects / Q000378:metabolism; D000199:Actins / Q000378:metabolism*; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D004136:Dinitrobenzenes / Q000494:pharmacology; D004721:Endoplasmic Reticulum / Q000187:drug effects / Q000378:metabolism*; D007181:Inclusion Bodies, Viral / Q000187:drug effects / Q000378:metabolism; D007425:Intracellular Membranes / Q000187:drug effects / Q000378:metabolism; D018551:Solanum lycopersicum / Q000821:virology*; D008870:Microtubules / Q000187:drug effects / Q000378:metabolism; D009218:Myosins / Q000378:metabolism*; D019590:Nucleocapsid Proteins / Q000378:metabolism*; D019441:Plant Epidermis / Q000166:cytology / Q000187:drug effects; D018515:Plant Leaves / Q000166:cytology / Q000187:drug effects; D010940:Plant Proteins / Q000378:metabolism*; D021381:Protein Transport / Q000187:drug effects; D013424:Sulfanilamides / Q000494:pharmacology; D053778:Thiazolidines / Q000494:pharmacology; D014026:Nicotiana / Q000166:cytology / Q000187:drug effects / Q000821:virology; D017865:Tospovirus; D014771:Virion / Q000378:metabolism*
chemical_list: D000199:Actins; D019086:Bridged Bicyclo Compounds, Heterocyclic; D004136:Dinitrobenzenes; D019590:Nucleocapsid Proteins; D010940:Plant Proteins; D013424:Sulfanilamides; D053778:Thiazolidines; C099603:nucleocapsid protein, Tospovirus; C012465:oryzalin; D009218:Myosins; C037068:latrunculin B; D004121:Dimethyl Sulfoxide
keywords: Tomato spotted wilt tospovirus; actin filaments; endoplasmic reticulum; intracellular movement; myosin motor; nucleocapsid