1Laboratory of Molecular Neuropathology, Jiangsu Key Laboratory of Translational Research and Therapy for Neuropsychiatric Disorders, Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou 215123, China
2Institute of Precision Medicine, Xiangya Hospital, Xiangya Medical School, Central South University, Changsha 410078, China

Abstract 

Parkinson’s disease (PD) is the most common neurodegenerative movement disorder. Mutations in the DJ-1, including L166P, are responsible for recessive early-onset PD. Many lines of evidence have shown that L166P is not only a loss-of-function mutant, but also a pro-apoptotic-like protein that results in mitochondrial dysfunction. L166P has been reported to be unstable and to mislocalize to mitochondria. However, the mechanisms underlying the instability of L166P compared to wild-type DJ-1 remain largely unknown. Here, we showed that Omi/HtrA2, a mitochondrial serine protease that has also been linked to the pathogenesis of PD, contributed to L166P instability. Omi directly interacted with and cleaved L166P in mitochondria to decrease the L166P level. However, Omi did not bind and cleave wild-type DJ-1. Moreover, Omi cleaved L166P at both serine residues 3 and 121, while L166P-induced cell death under H2O2 treatment was alleviated by over-expression of Omi. Our data reveal a bridge between DJ-1 and Omi, two PD-associated genetic factors, which contributes to our understanding of the pathogenesis of PD.

Keywords

Parkinson’s disease; DJ-1; L166P; Instability; Omi/HtrA2; Cleavage

[SpringerLink]