UAS regulatory sequences drive expression of a truncated form of Hsap\ATXN3 consisting of an expanded length glutamine tract (78 repeats) interrupted by CAA codons, flanked upstream by 12 amino acids and downstream by the carboxy terminal 43 amino acids of Hsap\ATXN3. The Hsap\ATXN3 protein is tagged at the N-terminal end with the Tag:HA epitope.