MFN2 and proteostasis deficiencies: While this analysis highlighted the previous trend of increased protein expression in proteopathy-associated cells (i.e., synaptic markers, Fig. 6a, Additional file 1: Fig. S5B) it revealed some functional neuronal subsets based on mitochondrial proteins and ubiquitination, e.g., MITOFUSION 2 (MFN2) (Fig. 6a, clusters 1, 2, 3, 4, 10) and POLYUBIQUITIN K48 (Fig. 6a, clusters 1, 2, 8).