RAB10 and Parkinson disease: As dopaminergic cell loss in SNc is a hallmark of PD pathology, and mutant LRRK2 causes PD, it is important to determine where LRRK2 substrates, Rab10 and pRab10 localize to the SNc. Immunofluorescence experiments were performed in C57BL/6J WT mouse brain sections. Low magnification images show that both Rab10 and pRab10 were expressed in the SNc (Fig. 4a, c).