title: Trypsin increases pseudorabies virus production through activation of the ERK signalling pathway.
abstract: Extracellular proteases that are expressed in primary and secondary foci of viral infection are potentially important mediators of infectious inflammatory processes. For some viruses, such as influenza virus and rotaviruses, proteases such as trypsin enhance infectivity by a direct proteolytic effect on some virion proteins. By using an in vitro model of herpesvirus infection, the possibility that proteases modulate the viral cycle through signalling delivered to the infected cell was investigated. It is reported that exposure of pseudorabies virus-infected cells to trypsin increased virus production. Moreover, this treatment induced synergistic and sustained activation of the extracellular signal-regulated kinase (ERK) 1/2 signalling pathway, which appeared to be necessary for this increased viral production. These results suggest that herpesviruses could take advantage of the inflammatory context and particularly of the presence of proteases to increase their replication. Thus, these data point to a potentially important role of extracellular proteases in herpesvirus infection.
authors.affiliation: Unité de Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique, Domaine de Vilvert, 78352 Jouy-en-Josas Cedex, France.
authors.forename: Béatrice
authors.initials: B
authors.lastname: Riteau
authors.affiliation: Unité de Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique, Domaine de Vilvert, 78352 Jouy-en-Josas Cedex, France.
authors.forename: Christiane
authors.initials: C
authors.lastname: de Vaureix
authors.affiliation: Unité de Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique, Domaine de Vilvert, 78352 Jouy-en-Josas Cedex, France.
authors.forename: François
authors.initials: F
authors.lastname: Lefèvre
mesh_terms: D000818:Animals; D002417:Cattle; D002460:Cell Line; D011558:Herpesvirus 1, Suid / Q000502:physiology*; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism*; D011557:Pseudorabies / Q000821:virology; D013552:Swine; D014357:Trypsin / Q000494:pharmacology*; D014779:Virus Replication / Q000187:drug effects*
chemical_list: D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D014357:Trypsin