Parkinson's disease (PD) is a major neurodegenerative disease.One of the known genetic contributors to PD pathogenesis is leucine-rich repeat kinase 2 (LRRK2) whose mutations with elevated kinase activity could lead to both familial and sporadic PD.However,how the pathogenic kinase activity of LRRK2 is regulated remains largely unclear.Here we report that peroxiredoxin 2 (Prx2) was identified as a novel interacting protein to LRRK2 with preferential expression in dopaminergic neurons over other Prx proteins.We also confirmed that Prx2 interacted with LRRK2 through its COR domain and its overexpression significantly decreased the kinase activity of mutant LRRK2.Functionally,overexpressed Prx2 rescued the transfected cells from LRRK2 mutant induced apoptotic processes.Importantly,overexpressed Prx2 reversed the altered subcellular distribution of cation-independent mannose 6-phosphate receptor (CI-M6PR) induced by PD-mutant LRRK2.Our results suggest that,by interacting with LRRK2,Prx2 may play an inhibitory role in the LRRK2 mediated cellular toxicity in PD by inhibiting its kinase activity.