Varicella-Zoster Virus induces PKR activation and its localization to the nuclei of infected cells

PKR is a protein belonging to the eIF2α kinase family, which comprises four enzymes activated in response to various stresses. These stresses can be extrinsic, such as a viral infection or heat shock, or intracellular, such as endoplasmic reticulum stress. When activated, these kinases phosphorylate the translation initiation factor eIF2α, which blocks cap-dependent translation and triggers the integrated stress response to restore cellular homeostasis. In the case of viral infection, PKR recognizes double-stranded RNA and initiates an innate antiviral response by inhibiting the translation of viral proteins, thereby limiting their replication. Our work shows that VZV infection activates PKR and induces its localisation in nuclear foci in infected cells.