SNCA and Parkinson disease: Similarly, studies show an increase in eIF2α phosphorylation in PD patients, closely associated with the accumulation and aggregation of α-synuclein, suggestive of endoplasmic reticulum stress due to misfolded proteins and increased protein translation through the unfolded protein response [23,24]; the phosphorylation of eIF2α also causes the inhibition of global translation [25], potentially representing an attempt by affected neurons to restore proteostasis.