PKR (Protein Kinase-R) is a 68-kDa serine–threonine kinase that appears to play a primary role in mediating the antiviral activities of infected cells. PKR mediates apoptosis induced by many different stimuli, such as LPS (Lipopolysaccharides), TNF-Alpha (Tumour Necrosis Factor-Alpha), viral infection, or serum starvation. Viral infection leads to the increased expression and secretion of the cytokine IFN-Gamma (Interferon- Gamma) from host cells. IFN-gamma induces the dsRNA (Double-Stranded RNA)-dependent PKR. dsRNA, produced during viral replication, is an active component of a viral infection that stimulates antiviral responses in infected cells (Ref.1). The PKR protein is enzymatically inactive unless it is activated by binding to dsRNA. PKR activates as a kinase upon binding to dsRNA. Two DRBD (dsRNA Binding Domains) termed DRBDI [...]