General control of amino acid synthesis 1-like protein 1 (GCN1)

GCN1 is a large, evolutionarily conserved cytoplasmic protein with HEAT repeats that functions as an essential activator of the eIF2α kinase GCN2 during amino acid starvation and diverse stress conditions. It binds directly to stalled and colliding ribosomes (disomes), acting as a sensor and scaffold to recruit GCN2, which then phosphorylates eIF2α, triggering the integrated stress response and altering global protein synthesis. GCN1 also promotes protein quality control, targeting factors such as eEF1α and eRF1 for degradation after ribosome stalling, and helps maintain protein homeostasis and prevent the accumulation of defective proteins. These mechanisms are critical for cellular adaptation to stress, regulation of cell growth, and prevention of neurodegenerative diseases. GCN1's multifaceted roles in translation control and proteostasis make it a potential therapeutic target for modulating stress responses and protein aggregation pathologies.

Other names

Stalled ribosome sensor GCN1GCN1L1KIAA0219HsGCN1GCN1LPRIC295eIF2 alpha kinase activator homologTranslational activator GCN1

Drugs may modulate ribosomal stalling or the degradation of translation factors by targeting GCN1-mediated pathways. Activation of GCN2 kinase via ribosome collision sensing, leading to eIF2α phosphorylation and translational repression.