Expression and subcellular location of the NSM protein of tomato spotted wilt virus (TSWV), a putative viral movement protein.
The 33.6-kDa nonstructural (NSM) protein gene, located on the ambisense M RNA segment of tomato spotted wilt virus (TSWV), was cloned and expressed using the Escherichia coli pET-11t expression system. The protein thus produced was purified and used for the production of a polyclonal antiserum. Western immunoblot analyses of TSWV-infected Nicotiana rustica plants showed NSM synthesis only during a short period early in systemic infection. Although NSM was found associated with cytoplasmic nucleocapsid preparations, it was absent from purified virus particles. Analyses of subcellular fractions from young, systemically infected leaves showed the presence of NSM in fractions enriched for cell walls and cytoplasmic membranes, respectively. Furthermore, immunogold labeling of tissue sections of TSWV-infected N. rustica plants showed that this protein was found associated with nucleocapsid aggregates in the cytoplasm and in close association with plasmodesmata. The data obtained provide evidence that NSM represents the viral movement protein of TSWV, involved in cell-to-cell movement of nonenveloped ribonucleocapsid structures.
Kormelink
R
R
Department of Virology, Wageningen, The Netherlands.
Storms
M
M
Van Lent
J
J
Peters
D
D
Goldbach
R
R
D000818:Animals; D000914:Antibodies, Viral; D001483:Base Sequence; D001692:Biological Transport; D002451:Cell Compartmentation; D004926:Escherichia coli / Q000235:genetics; D016253:Microscopy, Immunoelectron; D008969:Molecular Sequence Data; D009036:Moths / Q000166:cytology; D017924:Nucleopolyhedroviruses / Q000235:genetics; D053830:Plant Viral Movement Proteins; D010947:Plants, Toxic; D011994:Recombinant Proteins / Q000096:biosynthesis; D013347:Subcellular Fractions; D014026:Nicotiana / Q000382:microbiology; D017865:Tospovirus / Q000235:genetics*; D017361:Viral Nonstructural Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D014764:Viral Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology
D000914:Antibodies, Viral; D053830:Plant Viral Movement Proteins; D011994:Recombinant Proteins; D017361:Viral Nonstructural Proteins; D014764:Viral Proteins