ATXN3 and Machado-Joseph disease: In light of this, it was shown that ATXN2 expression downregulates mutant ataxin-3 and mitigates the disease-associated symptoms in Machado-Joseph disease/Spinocerebellar ataxia type 3 (MJD/SCA3) mice models, while the overexpression of PABPC1 (the gene encoding PABP-1) or the ablation of the PAM2 domain in the ATXN2 protein do not produce such effects.