ATXN1 and Machado-Joseph disease: In fact, many different studies showed that phosphorylation and other posttranslational modifications of polyQ proteins might be implicated in different aspects of pathogenesis, either decreasing or enhancing neurodegeneration in HD, SCA1, and MJD (Humbert et al., 2002; Chen et al., 2003; Emamian et al., 2003; Luo et al., 2005; Pennuto et al., 2009; Warby et al., 2009; Matos et al., 2016).