SOD1 and amyotrophic lateral sclerosis: In the transgenic SOD1G93A ALS rat model unfolded protein response and ER stress-induced apoptosis has been observed (Atkin et al., 2006); an unfolded protein response, including induction of stress sensor kinases, chaperones, and apoptotic mediators, has been shown also in spinal cord motor neurons of human patients with the sporadic form of ALS (sALS) that is not restricted to SOD1 mutations (Atkin et al., 2008).