ATF4 and cystic fibrosis: PERK may orchestrate maladaptive effects in CFs because multiple downstream PERK signaling molecules, such as CHOP, ATF4, DR5, and Bcl-2, have been shown to influence CF apoptosis (Mayorga et al., 2004; Humeres et al., 2014; Sokolova et al., 2017; Feng et al., 2018; Olivares-Silva et al., 2021; Tanner and Grisanti, 2021).