Fig. 5

A proposed working model of apoptosis regulated by USP18 through the PERK-eIF2α-ATF4 signaling pathway. USP18 inhibits the expression of CHOP, a marker gene of ER stress, by regulating the PERK-eIF2α-ATF signaling pathway, which relieves the inhibition of downstream anti-apoptotic protein Bcl-2, thereby inhibiting cell apoptosis. USP18 can also directly affect apoptosis by regulating the classical mitochondrial-mediated apoptosis pathway. Solid arrows indicate promotion, and dashed arrows indicate inhibitory effects.