PKR also known as EIF2AK2 is a serine/threonine protein kinase that is activated by autophosphorylation after binding to dsRNA. PKR plays a crucial role in the cellular response to viral infections by acting as an interferon-inducible, RNA-dependent protein serine/threonine kinase. PKR′s primary function is to phosphorylate the α subunit of the protein synthesis initiation factor eIF-2, specifically at serine-51, which leads to the inhibition of translation and effectively halts viral replication. This mechanism is vital for the host′s defense against viral pathogens, as PKR prevents the production of viral proteins. PKR is characterized by distinct structural domains, with the serine/threonine kinase catalytic domains located in the carboxy-terminal half and the RNA-binding domains situated in the amino-terminal region.