ATXN2 and amyotrophic lateral sclerosis: In addition, TDP-43 is simultaneously found to interact with other critical proteins in ALS namely matrin-3 (Johnson et al., 2014), ataxin-2 (Nihei et al., 2012), VAPB (Stoica et al., 2014), and SOD1 (Volkening et al., 2009) and is therefore rather tempting to conjecture about a tight interrelation between Ca2+ dyshomeostasis and the involvement of critical proteins in ALS.