Kinase Family PEK
PEK Kinases respond to a number of different stresses by phosphorylating translation initiation factor 2 (eIF2), reducing translation and activating stress responsive genes or inducing apoptosis. The vertebrate-specific PKR subfamily is activated by viral double-stranded RNA, PEK is activated by unfolded ER proteins, HRI by heme and GCN2 by uncharged tRNAs during nutritional stress.
Classification and Evolution
PEKs are found in all eukaryotes, though individual subfamilies are restricted or lost in specific lineages.
The PEK family has the following subfamilies: