ATXN3 and Machado-Joseph disease: Mutant flies, expressing the expanded human ATXN3, unveiled key pathways and validated the toxicity of several protein interactions in SCA3 disorder (Bilen and Bonini, 2007; Alves et al., 2010; Zhang et al., 2010; Vobfeldt et al., 2012; Xu et al., 2015; Bonini, 2022).