Baculoviruses have gained recognition for their use as eukaryotic expression vectors and potential use as insecticides. The virus which is the focus of this proposal has been developed for use as an insecticide against the Douglas-fir tussock moth which is a forest pest. Currently enough of the virus has been produced to treat 300,000 acres of forest land. Baculoviruses are unique in a number of ways. They produce two distinct forms of nucleocapsids at different times in their life cycle. One serves to spread the virus from cell to cell, whereas the other is occluded in a crystal protein matrix and is stable for many years in the environment. Both polyhedrin and another protein, p10, which is of unknown function, are produced at high levels late in infection (probably at higher levels than any other proteins of eukaryotic viruses). We have produced monoclonal antibodies (MAbs) to polyhedrin, p10 protein and several other structural proteins. In addition, we have constructed a lambda gtll library of the viral DNA and used the antibodies to isolate their corresponding characterize the expression of the proteins using immunofluorescent straining and Western blots. We propose to continue the investigation of viral genes and their products. We will use immunoelectron microscopy to investigate the relationship of the structural protein to each other and to structures within infected cells. We will produce antibodies to open reading frames we have sequenced and transcriptionally mapped to identify and characterize their gene products. In addition we will produce MAbs to structural proteins of budded virus which have a different phenotype from the occluded virus. The use of these antibodies in conjunction with the MAbs we already have against structural proteins of occluded virions will allow us to isolate the corresponding gels from the lambda gtll library and will allow us to investigate the expression of these proteins at both the transcriptional and translational level. In addition, because of a preliminary observation that p10 is capable of undergoing self- assembly and may have a relationship with a host cytoskeletal protein, we will begin investigating these phenomena.
