Previously, p62 (also known as SQSTM1), a protein implicated in protein aggregate formation and stalled autophagy, was shown to accumulate as the disease progresses in the G93A mouse spinal cord (Gal et al, 2007). Since p62 recruitment and accumulation at mitochondria have been associated with increased ROS production as well as mitochondrial membrane depolarization (Narendra et al, 2010), we next assessed the levels of p62 in the mitochondrial fraction in these patient‐derived cells. Indicative of aberrant autophagy stall, we observed a 3.3‐fold increased mitochondrial recruitment of p62, which was reduced by P110 treatment to 1.9‐fold relative to controls (Fig EV1D and E), indicting an interplay between mitochondrial fragmentation via Drp1/Fis1 interaction and autophagy balance.