Essential Role of Enterovirus 2A Protease in Counteracting Stress Granule Formation and the Induction of Type I Interferon

Abstract

Enteroviruses are important pathogens that can cause a variety of diseases in humans, including aseptic meningitis, myocarditis, hand-foot-and-mouth disease, conjunctivitis, and acute flaccid paralysis. Like many other viruses, enteroviruses must counteract antiviral cellular responses to establish an infection. It has been suggested that enterovirus proteases cleave cellular factors to perturb antiviral pathways, but the exact contribution of viral proteases 2A pro and 3C pro remains elusive. Here, we show that 2A pro , but not 3C pro , of all four human EV species (EV-A to EV-D) inhibits SG formation and IFN-β gene transcription. Our observations suggest that enterovirus 2A pro has a conserved function in counteracting antiviral host responses and thereby is the main enterovirus “security protein.” Understanding the molecular mechanisms of enterovirus immune evasion strategies may help to develop countermeasures to control infections with these viruses.