The ALS/FTLD causative genes classified into Group 1 specifically decreased solubility of both TDP-43∆NLS-EGFP (Fig. 3B) and endogenous TDP-43 (Fig. 3C), supporting the notion that MRPs and RBPs are tightly involved in TDP-43 cytoplasmic aggregation. This evidence concerns the gene TARDBP and amyotrophic lateral sclerosis.