Identification and characterization of bovine herpesvirus-1 glycoproteins E and I

To identify the products of the bovine herpesvirus-1 (BHV-1) gE and gI genes, we constructed baculovirus recombinants containing the putative gE or gI genes. These recombinant viruses synthesized BHV-1 gE and gI with apparent molecular masses of 84 and 41 kDa, respectively. Polyclonal antibodies against these recombinant gE or gI proteins were produced and by using these antibodies, we showed the presence of gE and gI with apparent molecular masses of 94 and 45 kDa, respectively, in purified BHV-1 virions. We also demonstrated that like their herpes simplex virus-1 and pseudorabies virus counterparts BHV-1 gE and gI form a complex. A gI- BHV-1 mutant failed to express gI but gE was found in the virions. On the other hand, neither gE nor gI was found in the virions of a gE- BHV-1 mutant. In the gE- BHV-1 mutant, gI was produced but released into the medium without being integrated in the virions.