SOD1 and amyotrophic lateral sclerosis: The SOD1 mutations produce the insoluble SOD1 ubiquitin-positive inclusion body in the motor neurons (MNs) of ALS patients, which interferes the folding and synthesis and removal of proteins as well as proteasome degradation, leading the degradation dysfunction of abnormal and toxic proteins as well as the misfolding and aggregation of proteins such as mutative SOD1 in ALS.