Immunoprecipitation of a 50-kDa protein: a candidate receptor component for tomato spotted wilt tospovirus (Bunyaviridae) in its main vector, Frankliniella occidentalis.
A 50-kDa protein that binds to viral particles in solid-phase assays and that is recognized by anti-idiotypic antibodies made against anti-viral glycoproteins G1/G2 (anti-Ids) has been proposed as a receptor candidate for tomato spotted wilt tospovirus (TSWV) in its main thrips vector, Frankliniella occidentalis Pergande (Bandla et al., 1998. Phytopathology 88, 98-104). Here we show the immunoprecipitation of the 50-kDa protein by anti-Ids and by an anti-G1/G2-TSWV conjugate - a new immunoprecipitation method. In addition, we show that anti-Ids made against anti-G1 (anti-IdG1) block virus replication in an insect tissue replication assay. The results indicate that (a) the TSWV-50-kDa protein interaction occurs in solution, as it must do in vivo; (b) G1 is a viral attachment protein; and (c) the 50-kDa protein is a candidate host factor essential for TSWV entry. These results provide additional support for the role of the 50-kDa thrips protein as a viral receptor. Additionally these experiments provide the basis for testing saturable binding and represent an important step toward the first cloning and identification of a cellular receptor for a plant virus.
Medeiros
R B
RB
Department of Plant Pathology, University of Wisconsin, Russell Labs, Madison, WI 53706, USA.
Ullman
D E
DE
Sherwood
J L
JL
German
T L
TL
D000818:Animals; D000906:Antibodies / Q000276:immunology / Q000494:pharmacology; D000911:Antibodies, Monoclonal / Q000276:immunology; D000914:Antibodies, Viral / Q000494:pharmacology; D000956:Antigens, Viral / Q000276:immunology; D004199:Disease Vectors; D006023:Glycoproteins / Q000276:immunology; D019476:Insect Proteins / Q000276:immunology / Q000302:isolation & purification*; D007313:Insecta / Q000737:chemistry* / Q000502:physiology; D018551:Solanum lycopersicum / Q000821:virology*; D011233:Precipitin Tests / Q000379:methods; D011991:Receptors, Virus / Q000302:isolation & purification*; D013997:Time Factors; D017865:Tospovirus / Q000737:chemistry* / Q000187:drug effects; D014764:Viral Proteins / Q000276:immunology; D014779:Virus Replication / Q000187:drug effects
D000906:Antibodies; D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D000956:Antigens, Viral; D006023:Glycoproteins; D019476:Insect Proteins; D011991:Receptors, Virus; D014764:Viral Proteins