PARK7 and Parkinson disease: Similarly to our current studies on excitotoxicity, we reported previously that levels of the ATP synthase F1 β subunit are low in aged DJ-1 deficient, Parkinson’s Disease (PD) mouse model brain and in patient-derived cell lines, while the c-subunit levels are normal, suggesting that mutant DJ-1-induced degenerative disease is associated with a reduction in F1/c ratio with resultant ACLC activation [56].