The protein kinase regulated by RNA (PKR) enhances both activation of mitogen-activated protein kinases and the induction of interferon beta (IFN-β) by measles virus defective in C-protein expression (C ko). Here we used complementation of human cell lines stably deficient in PKR (PKR kd) to probe the basis of these PKR-mediated responses. We found that PKR kd HeLa and amnion U cell lines were defective for virus-mediated activation of IFN induction signaling components compared to PKR-sufficient control cells. Complementation of PKR kd cells with wildtype PKR, but not with PKR mutants defective in either catalytic activity or dsRNA-binding activity, restored JNK, p38 and ATF-2 phosphorylation and enhanced IFN-β induction following infection. By contrast to mammalian PKR, the Z-DNA binding domain-containing fish homologue of PKR, PKZ, lacked the capacity to enhance C ko virus-mediated IFN-β induction. Furthermore, inhibition of virus growth was observed with C ko-infected PKR kd cells complemented with PKR but not with PKZ. © 2012 Elsevier Inc.
Taghavi, N., & Samuel, C. E. (2012). Protein kinase PKR catalytic activity is required for the PKR-dependent activation of mitogen-activated protein kinases and amplification of interferon beta induction following virus infection. Virology, 427(2), 208–216. https://doi.org/10.1016/j.virol.2012.01.029