GCN2

2023-05-07: Serine-Threonine Protein Kinase

GCN2 (general control nonderepressible 2)) #

• Amino acid starvation leads to high levels of uncharged tRNA: tRNA binds to the C-terminus, which is homologous to histidyl-tRNA synthetase, next to the kinase catalytic moiety. After binding, GCN2 dimerizes by going from antiparallel to parallel position, whereby it is activated, and ATP can bind and it then autophosphorylates for max kinase activity.
• Phosphorylates eIF-2α at Ser51, which subsequently increases the affinity for eIF2B (a GEF) to sequester eIF-2α.
  • eIF-2α-p activates ATF4 activates FGF21.