There is a wealth of evidence that mutant TDP-43 [107], overexpressed mutant human FUS [108], and mutant SOD1 [109,110] accumulate inside the mitochondria of ALS patients, Drosophila models, and SOD1 mouse brain tissue, respectively, and cause defective mitochondrial complex activities, impaired protein homeostasis and reduced mitochondrial ATP production [111,112]. This evidence concerns the gene TARDBP and amyotrophic lateral sclerosis.