eIF-2-alpha kinase activator GCN1 (GCN1)

Acts as a positive activator of the EIF2AK4/GCN2 protein kinase activity in response to amino acid starvation. Forms a complex with EIF2AK4/GCN2 on translating ribosomes; throughout this procedure, GCN1 appears to act as a chaperone to facilitate delivery of uncharged tRNAs that enter the A site of ribosomes into the tRNA- binding domain of EIF2AK4/GCN2, and hence stimulating EIF2AK4/GCN2 kinase activity.

Participates in the repression of global protein synthesis and in gene-specific mRNA translation manipulation, like the transcriptional activator ATF4, by encouraging the EIF2AK4/GCN2-mediated phosphorylation of eukaryotic translation initiation factor 2 (eIF-2-alpha/EIF2S1) on'Ser-52', and hence enabling ATF4-mediated reprogramming of amino acid biosynthetic gene expression to alleviate nutrient deficiencies. .