Eukaryotic translation initiation factor 2B subunit epsilon (eIF2Bε)

Eukaryotic translation initiation factor 2B subunit epsilon (eIF2Bε) is the catalytic subunit of eIF2B, a multi-subunit enzyme complex that acts as a guanine nucleotide exchange factor for eukaryotic initiation factor 2 (eIF2), a key GTPase in protein translation initiation[1][2][5]. eIF2Bε, encoded by the *EIF2B5* gene, facilitates the exchange of GDP for GTP on eIF2, regulating protein synthesis rates in response to cellular conditions[4][6]. The complex is critical for modulating the integrated stress response (ISR), as its inactivation under stress conditions represses general translation but enhances selective expression of stress-response proteins[2]. Mutations in the *EIF2B5* gene are causative for leukoencephalopathy with vanishing white matter, a progressive neurodegenerative disorder[4]. The eIF2B complex, particularly its epsilon subunit, is considered a potential therapeutic target for modulating protein synthesis in neurodegenerative diseases and other ISR-related pathologies[2][6].

Other names

EIF2B5eIF-2B epsilonEIF2BepsilonCACHCLEVWM5LVWMeukaryotic translation initiation factor 2B, subunit 5 epsiloneukaryotic translation initiation factor 2B, subunit 5 εEIF2B ε

Inhibition (by phosphorylated eIF2α or by ISR-targeting compounds); Activation (by GTP recycling promotion on eIF2)