SOD1 and amyotrophic lateral sclerosis: In addition, another epigenetic modulator, known as sumoylation was shown to regulate localization of EAAT2 expression in SOD1-G93A mouse model of inherited ALS, wherein the cytosolic carboxy-terminal domain is cleaved from EAAT2, conjugated to SUMO1, and results in the accumulation of EAAT2 in the cytoplasm instead of expression in the plasma membrane (Foran et al., 2014).