Reduction of phospholipase D activity during coxsackievirus infection.

During enterovirus infection, host cell membranes are rigorously rearranged and modified. One ubiquitously expressed lipid-modifying enzyme that might contribute to these alterations is phospholipase D (PLD). Here, we investigated PLD activity in coxsackievirus-infected cells. We show that PLD activity is not required for efficient coxsackievirus RNA replication. Instead, PLD activity rapidly decreased upon infection and upon ectopic expression of the viral 3A protein, which inhibits the PLD activator ADP-ribosylation factor 1. However, similar decreases were observed during infection with coxsackieviruses carrying defective mutant 3A proteins. Possible causes for the reduction of PLD activity and the biological consequences are discussed.