Glutamate transporter-1 has been shown to be sumoylated under normal physiological conditions in primary astrocytes, wt rat cortex homogenates and non-ALS control post-mortem tissue with lysine 570 being the primary target for sumoylation of GLT-1 (Fei et al., 2006; Foran et al., 2014). This evidence concerns the gene SLC1A2 and amyotrophic lateral sclerosis.