Biological evaluation of glycoproteins mapping to two distinct mRNAs within the BamHI fragment 7 of pseudorabies virus: expression of the coding regions by vaccinia virus.

Several glycoproteins from the unique short region of pseudorabies have been identified and characterized. The genes encoding at least four glycoproteins (gp50, gp63, gl, and gX) are located within the BamHI fragment 7 of pseudorabies. S1 nuclease mapping was used to determine that a 2.4-kb mRNA encompasses the coding region for gp50 and gp63 and probably represents a colinear transcript for these proteins. Using the same technique, a 2.8-kb mRNA was found to encode gl. No other mRNAs were found to be encoded on the opposite strand of DNA in this region. Various recombinant vaccinia vectors were made incorporating the coding regions for these two mRNAs. Pseudorabies recombinant vaccinia infected ST cells expressed glycoproteins that co-migrated with the authentic PRV glycoproteins upon polyacrylamide electrophoresis. Intracranial or intraperitoneal inoculation of mice with the recombinant viruses constructed to contain the mRNA coding regions resulted in various degrees of protection from a lethal challenge of pseudorabies virus.