RNA-dependent protein kinase PKR and the Z-DNA binding orthologue PKZ differ in their capacity to mediate initiation factor eIF2α-dependent inhibition of protein synthesis and virus-induced stress granule formation.
Protein kinase R (PKR), a regulator of translation in mammalian cells, possesses two ds-RNA binding domains responsible for kinase activation. Protein kinase Z (PKZ), a PKR-like kinase present in fish, possesses two Z-DNA binding domains. A complementation strategy with cells stably deficient in PKR was used to compare the functions of PKR and PKZ. We found… (More)