VPS35 Protects Against TMEM230-Mutation-Induced Progressive Locomotor Deficits in Drosophila
Abstract BackgroundRecently, four Parkinson’s disease (PD)-linked mutations (Y92C, R141L, 184PGext*5 and 184Wext*5) in transmembrane protein 230 (TMEM230) were identified in PD patients, and these mutations have implications in protein trafficking and neurodegeneration. However, there is a lack of in vivo studies on the roles of PD-related variants of TMEM230 in PD pathogenesis.MethodsIn this study, we generated human wild-type (WT) and mutant TMEM230 (Y92C, R141L, 184PGext*5 and 184Wext*5) transgenic Drosophila using isoform Ⅱ cDNA. ResultsWe found that the expression of TMEM230 184PGext*5 in pan-neurons or dopaminergic neurons in Drosophila induced PD-like phenotypes, which included impaired locomotor ability, a shortened lifespan, reduced TH levels, and increased phosphorylated JNK and cleaved caspase-3 levels. Moreover, rotenone, a common pesticide, enhanced TMEM230-184PGext*5-induced PD-like phenotypes. In contrast, the overexpression of wild-type (WT) VPS35 rescued TMEM230-184PGext*5-induced PD-like phenotypes, while the knockdown of VPS35 by RNA interference (RNAi) or the expression of mutant VPS35 D620N worsened PD-like phenotypes. ConclusionThese results indicate that VPS35, as a downstream effector of TMEM230, plays a critical role in TMEM230-linked JNK/caspase-3 signalling pathways and that mutations in TMEM230 and VPS35 disrupt these pathways, resulting in dopaminergic neurodegeneration and PD-like phenotypes. These findings provide novel insight into the molecular mechanisms of mutant TME230- and VPS35-induced abnormalities underlying the pathogenesis of PD.