Without VPS13C, phospho-Rab10 dynamics on the lysosomal membrane are disrupted, resulting in enlarged lysosomes that are more tethered, less motile, and ultimately dysfunctional with impaired acidification and hydrolytic activity (Fig. 7 K), potentially contributing to the pathogenesis observed upon loss of VPS13C in PD. Here, RAB10 is linked to Parkinson disease.