Environmental Toxin Rotenone Drives LRRK2-Mediated Microtubule, Cilia and Proteostasis Disruption in Parkinson's Disease Model

Abstract

Exposure to the environmental toxin rotenone increases risk for Parkinsons disease (PD). However, protein phosphorylation changes induced by rotenone in neural-derived cells have not been reported. We examined the effect of rotenone on the proteome and phosphoproteome of cortex-derived cultures from wild-type and Lrrk2-/- mouse brains. We also analyzed the phosphoproteome of the PD cadaver brain using a previously unanalyzed dataset. Rotenone alters phosphorylation at 904 sites, most of which are unchanged in Lrrk2-/- cultures. Common targets include proteins that control microtubule stability, vesicular transport, and protein clearance via the autophagosomal/lysosomal pathway. Analysis of phosphosites with known function indicate that rotenone activates histone deacetylase-1 and represses the pro-survival transcriptional regulators Mef2C and Mef2D, while inhibiting translation by phosphorylating Eif2b5. These effects do not occur in Lrrk2-/- cultures. This study shows that Lrrk2 is required the earliest rotenone-triggered phospho-signalling events.