10xUAS regulatory sequences drive expression of the fra coding sequence, in which all nine of the cytoplasmic tyrosines have been mutated (amino acid replacements Y1113F, Y1170F, Y1189F, Y1193F, Y1207F, Y1212F, Y1247F, Y1250F, and Y1313F). The coding sequence is tagged at the C-terminal with six copies of Tag:MYC.