A G1 glycoprotein epitope of La Crosse virus: a determinant of infection of Aedes triseriatus.
Arthropod-borne viruses (arboviruses) have specific vector-vertebrate host cycles in nature. The molecular basis of restriction of virus replication to a very limited number of vector species is unknown, but the present study suggests that viral attachment proteins are important determinants of vector-virus interactions. The principal vector of La Crosse (LAC) virus is the mosquito Aedes triseriatus, and LAC virus efficiently infects the mosquito when ingested. However, a variant (V22) of LAC virus, which was selected by growing the virus in the presence of a monoclonal antibody, was markedly restricted in its ability to infect Ae. triseriatus when it was ingested. Only 15% of the mosquitoes that ingested V22 became infected and 5% of these developed disseminated infections. In contrast, 89% of the mosquitoes that ingested LAC became infected and 74% developed disseminated infections. When V22 was passed three times in mosquitoes by feeding, a revertant virus, V22M3, was obtained that infected 85% of Ae. triseriatus ingesting this virus. In addition, V22M3 regained the antigenic phenotype and fusion capability of the parent LAC virus. These results suggest that the specificity of LAC virus-vector interactions is markedly influenced by the efficiency of the fusion function of the G1 envelope glycoprotein operating at the midgut level in the arthropod vector.
D000330:Aedes / Q000382:microbiology*; D000818:Animals; D000911:Antibodies, Monoclonal; D000956:Antigens, Viral / Q000276:immunology; D002043:Bunyaviridae / Q000254:growth & development*; D002141:Encephalitis Virus, California / Q000254:growth & development* / Q000276:immunology; D006023:Glycoproteins / Q000276:immunology / Q000502:physiology; D007303:Insect Vectors / Q000382:microbiology*; D007422:Intestines / Q000382:microbiology; D009500:Neutralization Tests; D014759:Viral Envelope Proteins / Q000276:immunology / Q000502:physiology*; D014779:Virus Replication
D000911:Antibodies, Monoclonal; D000956:Antigens, Viral; D006023:Glycoproteins; D014759:Viral Envelope Proteins