Fig. 1.

Domain organization of the four mammalian eIF2α kinases. Polypeptides are represented as bars running from N- to C-terminal domains from left to right. Length in amino acids is of the human proteins. SP signal peptide, TM transmembrane domain, KD kinase domain, DS RBD double-stranded RNA binding domain, PKD pseudokinase domain, His/Rs histidyl-tRNA synthetase-related domain, RB ribosome binding. Domains involved in sensing stress signals/activation are in green. Kinase domains are in yellow. Other domains are colored blue. Domains are drawn to scale