Proteolytic Processing of Human Cytomegalovirus Glycoprotein B Is Dispensable for Viral Growth in Culture

摘要: Glycoprotein B (gB) of human cytomegalovirus (HCMV), which is considered essential for the viral life cycle, proteolytically processed during maturation. Since gB homologues several other herpesviruses remain uncleaved, relevance this property HCMV infectivity unclear. Here we report on construction a mutant in recognition site cellular endoprotease furin was destroyed. Because mutagenesis proteins may result lethal phenotype, replication-deficient gB-null genome encoding enhanced green fluorescent protein constructed, and complementation by gBs initially evaluated transient-cotransfection assays. Cotransfection plasmids expressing authentic or with mutated cleavage (gB-ΔFur) led to formation miniplaques were from one cycle phenotypic genome. To verify these results, two recombinant genomes constructed: HCMV-BAC-ΔMhdI, deletion hydrophobic domain 1 that appeared be growth cotransfection experiments, HCMV-BACΔFur, amino acid substitution. Consistent results assays, only ΔFur replicated fibroblasts, showing kinetics comparable wild-type virus. mutant-infected cells whereas glycosylation transport cell surface not impaired. Extracellular virus contained exclusively uncleaved gB, indicating proteolytic processing dispensable replication culture.