Identification of a protein associated with circulative transmission of Barley yellow dwarf virus from cereal aphids, Schizaphis graminum and Sitobion avenae

Using 2-D electrophoresis and virus overlay assay, a 50-kDa protein (P50) exhibiting specific binding to purified virus particles of BYDV-GAV was found in the protein extracts from Schizaphis graminum and Sitobion avenae, two aphid species transmitting BYDV-GAV. P50 in the extracts of S. graminum was isolated by preparation electrophoresis and electro-eluted proteins from the gel slices for antiserum preparation. After feeding the antiserum through membrane, the transmission efficiencies of S. graminum and S. avenae for BYDV-GAV decreased significantly. It was suggested that P50 should be related with transmission pro- cess. Location of P50 was found at the plasma membrane surrounding the accessory salivary gland (ASG) in the head tissues of S. graminum by immunogold-labelling experiment. The ascertainment of the protein associated with virus transmission has a significance influence on further understanding the transmission mechanism and genetic engineering for resistant to vector transmission.