Proteolytic cleavage of bovine herpesvirus 1 (BHV-1) glycoprotein gB is not necessary for its function in BHV-1 or pseudorabies virus.

摘要: Glycoprotein B homologs represent the most highly conserved group of herpesvirus glycoproteins. They exist in oligomeric forms based on a dimeric structure. Despite high degree sequence and structural conservation, differences posttranslational processing are observed. Whereas gB herpes simplex virus is not proteolytically processed after oligomerization, other cleaved by cellular protease into subunits that remain linked via disulfide bonds. Proteolytic cleavage common for activation viral fusion proteins, it has been shown essential membrane events during infection, e.g., penetration direct cell-to-cell spread. To analyze importance proteolytic function homologs, we isolated mutant bovine 1 (BHV-1) expressing BHV-1 no longer because deletion site analyzed its phenotype cell culture. We showed previously can functionally substitute homologous glycoprotein pseudorabies (PrV), isolation PrV gB-negative recombinant expresses (A. Kopp T. C. Mettenleiter, J. Virol, 66:2754-2762, 1992). Therefore, also lacking but noncleavable gB. Our results show either or background. Compared with cleavable gB, did detectably alter phenotype, as plaque assays, one-step growth kinetics, kinetics. In mutant, uncleaved was equivalent to wild-type protein regard only slightly delayed kinetics compared parental BHV-1. However, resulting plaques were significantly smaller, indicating role spread