The multiple faces of proteinkinase R in antiviral defense

Various pattern recognition receptors (PRRs) have been implicated in the detection of viral RNA and subsequent interferon (IFN) gene expression, including the double-stranded RNA-dependent proteinkinase R (PKR). Now, a novel role of PKR has been unveiled, as it was shown that, upon the infection with certain viruses, PKR is crucial for the integrity of newly synthesized IFN mRNA, thereby generating an optimal host antiviral immune response. There is a need of future studies to investigate additional roles of PKR in innate immunity and the molecular understanding of this novel function of PKR.