SOD1 and amyotrophic lateral sclerosis: In line with this hypothesis, Neuregulin-1 expression, a factor present at the postsynaptic face of C-boutons, is diminished in MNs of an SOD1 mouse model and of ALS patients (Gallart-Palau et al., 2014; Lasiene et al., 2016), and its administration restores C-bouton numbers in mice (Lasiene et al., 2016).