Basal Lamina Determinants of Luteovirus Transmission: Role in Evolution of Virus-Vector Specificity

9419807 Cox-Foster Luteoviruses are small RNA viurses that infect all major food crops causing severe economic losses worldwide, yet they receive relatively little attention. To be transmitted by the insect vector, the aphid, the virus must enter the circulatory system through the gut and enter the salivary gland. The work in this proposal builds on the observation made by the principal investigators that the extracellular glycoprotein matrix of the basal lamina surrounding the aphid salivary gland regulates, in part, luteovirus transmission and vector specificity. The first objective of the work is to determine whether species-specific components of the basal lamina associate with transmissible viruses, but not with nontransmissible ones. The second objective is to identify specific surface domains on the virion protein capsid that interact with the basal lamina and function as virus-specific recognition sites permitting virus attachment and pentration into the salivary gland. Since almost nothing is known about virion penetration of the extracellular matrix components which comprise the basal lamina, the proposed work may give fundamental insight into the mechanism by which large protein aggregates, such as virions, actively move across these semipermeable barriers which would otherwise exclude them on the basis of size. %%% If the underlying hypothesis on basement membrane recognition is correct, the research is likely to make a major impact on our understanding of luteovirus biology and basement membrane fucntion. It would, furthermore, likely lead to new strategies to interfere with luteovirus life cycle, impacting on a significant agricultural problem. ***