title: A glycoprotein M-deleted equid herpesvirus 4 is severely impaired in virus egress and cell-to-cell spread.
abstract: To analyse the function of the equid herpesvirus 4 (EHV-4) glycoprotein M homologue (gM), two different mutated viruses (E4DeltagM-GFP and E4DeltagM-w) were generated. Both gM-negative EHV-4-mutants were characterized on complementing and on non-complementing cells and compared with E4RgM, a virus where gM-expression had been repaired. It was demonstrated in virus growth kinetics that deleting gM had a more dramatic influence on EHV-4 replication than expected. Extracellular infectivity was detected 9-12 h later than in EHV-4-infected Vero cells and titres were reduced up to 2000-fold. In addition, mean maximal diameters of plaques were less than 20 % of diameters of wild-type plaques. These results are in contrast to most other alphaherpesviruses, including the closely related equid herpesvirus type 1, where deletion of gM only marginally influences the ability of viruses to replicate in cell culture. Nevertheless, analysis of infected cells by electron microscopy did not reveal a specific defect for deleting gM. It was concluded that EHV-4 gM is important for more than one step in virus replication in cell culture, influencing both efficient virus egress and cell-to-cell spread.
authors.affiliation: Institute for Medical Microbiology, Infectious and Epidemic Diseases, Ludwig-Maximilians-Universität München, Veterinärstr. 13, D-80539 Munich, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Ziegler
authors.affiliation: Institute for Comparative Tropical Medicine and Parasitology, Ludwig-Maximilians-Universität München, Leopoldstraße 5, D-80802 Munich, Germany.
authors.forename: Frank T
authors.initials: FT
authors.lastname: Just
authors.affiliation: Boehringer Ingelheim Vetmedica GmbH, D-55216 Ingelheim, Germany.
authors.forename: Axel
authors.initials: A
authors.lastname: Lischewski
authors.affiliation: Boehringer Ingelheim Vetmedica GmbH, D-55216 Ingelheim, Germany.
authors.forename: Knut
authors.initials: K
authors.lastname: Elbers
authors.affiliation: Institute for Medical Microbiology, Infectious and Epidemic Diseases, Ludwig-Maximilians-Universität München, Veterinärstr. 13, D-80539 Munich, Germany.
authors.forename: Antonie
authors.initials: A
authors.lastname: Neubauer
mesh_terms: D000818:Animals; D002460:Cell Line; D002522:Chlorocebus aethiops; D017353:Gene Deletion; D005816:Genetic Complementation Test; D006023:Glycoproteins / Q000032:analysis / Q000235:genetics / Q000502:physiology; D023141:Herpesvirus 4, Equid / Q000235:genetics / Q000502:physiology*; D008854:Microscopy, Electron; D009154:Mutation; D014709:Vero Cells; D014758:Viral Core Proteins / Q000235:genetics / Q000502:physiology*; D014779:Virus Replication
chemical_list: D006023:Glycoproteins; D014758:Viral Core Proteins