GCN2 and PERK (GCN2 & PERK)

General control nonderepressible 2 kinase (GCN2) and protein kinase RNA-like endoplasmic reticulum kinase (PERK) are key members of the eIF2α kinase family, each responsible for phosphorylating eIF2α in response to distinct types of cellular stress. GCN2 is primarily activated by amino acid deprivation or accumulation of uncharged tRNA via its histidyl-tRNA synthetase-like domain, while PERK is mainly activated by endoplasmic reticulum (ER) stress due to unfolded protein accumulation[2][7][9]. Both kinases act as metabolic sensors, modulating translational output to promote survival or, when stress is unmanageable, cell death[2][3][4][5][7]. Their activity supports tumor cell adaptation to nutrient-poor environments and contributes to several disease processes, making them important therapeutic targets under investigation[5][8]. Recent studies reveal redundancy and cross-talk between their pathways; for example, both must be genetically ablated to fully suppress eIF2α phosphorylation in some stress contexts, and inhibitors designed for one can affect the other due to kinase homology[1][5]. Pairing both kinases into a single "target" entry is non-standard—each has distinct regulation and pharmacology, and structured data should ideally separate them for accuracy.

Other names

Eukaryotic translation initiation factor 2-alpha kinase 4EIF2AK4EIF2AK3PEKEukaryotic translation initiation factor 2-alpha kinase 3

Small molecule inhibitors block kinase activity (ATP-competitive inhibitors); Stress-mimicking compounds can differentially activate either kinase depending on cellular context