Therefore, PDI family members can reduce general ER stress levels in protein misfolding disorders as a part of the unfolded protein response [23], [54], [55], prevent the misfolding of amyloidogenic proteins through a direct interaction [23], [59]–[64], and prevent neurotoxicity associated with ER stress and protein misfolding [20], [23], [33], [59]–[61]. Here, P4HB is linked to proteostasis deficiencies.