Protein kinase RNA-like endoplasmic reticulum kinase (PERK)

Protein kinase RNA-like endoplasmic reticulum kinase (**PERK**) is a serine/threonine-protein kinase encoded by the *EIF2AK3* gene. It is a type I transmembrane enzyme located in the endoplasmic reticulum membrane, where it acts as a key sensor for misfolded proteins during cellular stress. Upon activation by ER stress, PERK dimerizes and autophosphorylates, leading to phosphorylation of eukaryotic translation initiation factor 2 alpha (**eIF2α**). This event suppresses general protein synthesis while selectively allowing translation of specific mRNAs involved in cell survival or apoptosis—most notably activating transcription factor 4 (**ATF4**) and C/EBP homologous protein (**CHOP**), which can drive pro-apoptotic gene expression if the stress is unresolved. PERK plays critical roles across multiple biological processes including adaptation to proteotoxic stresses, regulation of cell fate decisions between survival and programmed cell death, and maintenance of proteostasis. Dysregulation or mutation leads to human diseases such as Wolcott-Rallison syndrome; aberrant activation has been implicated in cancer progression, neurodegenerative disorders like Parkinson’s disease models, cardiovascular events like stroke recovery via modulation of neuronal survival after ischemia/reperfusion injury. Pharmacological inhibitors targeting PERK are being explored for therapeutic intervention but require careful consideration due to its central role in fundamental cellular processes.

Other names

Eukaryotic translation initiation factor 2-alpha kinase 3EIF2AK3PKR-like endoplasmic reticulum kinase

Inhibition of PERK activity to modulate the unfolded protein response and reduce ER-stress-induced apoptosis or cell death in various diseases, including cancer and neurodegeneration. Inhibitors block PERK’s ability to phosphorylate eIF2α, thereby affecting downstream signaling pathways such as ATF4/CHOP-mediated apoptosis.