P4HB and nervous system disorder: As noted above in the Introduction and Results sections, PDIs are associated with human diseases, including neurological diseases (Walker et al., 2010; Perri et al., 2015), and PDI modulators for therapeutic treatment are being developed (Ali Khan and Mutus, 2014; Xu et al., 2014; Okumura et al., 2015; Torres et al., 2015; Kaplan et al., 2015).