Herpes simplex virus type 1 infection stimulates p38/c-Jun N-terminal mitogen-activated protein kinase pathways and activates transcription factor AP-1.
Cells respond to environmental stress and proinflammatory cytokines by stimulating the Jun N-terminal kinase/stress-activated protein kinase (JNK/SAPK) and the p38 mitogen-activated protein kinase cascades. Infection of eukaryotic cells with herpes simplex virus type 1 (HSV-1) resulted in stimulation of both JNK/SAPK and p38 mitogen-activated protein kinase after 3 h of infection, and activation reached a maximum of 4-fold by 9 h post-infection. By using a series of mutant viruses, we showed that the virion transactivator protein VP16 stimulates p38/JNK, whereas no immediate-early, early, or late viral expressed gene is involved. We identified the stress-activated protein kinase kinase 1 as an upstream activator of p38/JNK, and we demonstrated that activation of AP-1 binding proceeded p38/JNK stimulation. During infection, the activated AP-1 consisted mainly of JunB and JunD with a simultaneous decrease in the cellular levels of Jun protein. We suggest that activation of the stress pathways by HSV-1 infection either represents a cascade triggered by the virus to facilitate the lytic cycle or a defense mechanism of the host cell against virus invasion.
Zachos
G
G
School of Biological and Biomedical Sciences, Glasgow Caledonian University, Cowcaddens Road, Glasgow, G4 0BA, United Kingdom.
Clements
B
B
Conner
J
J
D000818:Animals; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D002460:Cell Line; D006224:Cricetinae; D004789:Enzyme Activation; D017781:Genes, Immediate-Early; D018259:Herpesvirus 1, Human / Q000235:genetics / Q000502:physiology*; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D018808:Transcription Factor AP-1 / Q000378:metabolism*