SNO-PDI accentuates the misfolding of synphilin in Parkinson disease (Forrester et al., 2006) and S-nitrosylation also increases mutant SOD1 aggregation via incorrect disulphide cross-linking of the immature, misfolded mutant SOD1, leading to neuronal cell death (Jeon et al., 2014). Here, PDIA2 is linked to Parkinson disease.