ATXN1 and amyotrophic lateral sclerosis: However, protein products of ATXN2 interact with the TAR DNA binding protein-43 (TDP-43) resulting in TDP-43 mislocalization and aggregate formation, a hallmark of amyotrophic lateral sclerosis.15 Tazelaar et al.18 discovered that overexpression of ataxin-1 disturbs the nucleocytoplasmic transport of TDP-43.