Spinocerebellar ataxia type 3 is a rare neurodegenerative disease with autosomal transmission due a dominant mutation in the deubiquitinylase-encoding Sca3 gene. This disease is associated with the death of some neurons of the cerebellum, thus leading to equilibrium issues problems in movements coordination. Neurological anomalies progress toward death within 15 years. Spinocerebellar ataxia type 3 is characterized by insoluble Sca3 protein aggregates that remain localized in the cell. Depending on the hypothesis protein aggregation could either be toxic by inhibiting protein degradation systems or sequestering essential cellular components, or be protective by isolating toxic forms of the Sca3 protein. However, the relationship that links insoluble Sca3 with toxicity remains unclear.