UAS regulatory sequences drive expression of flfl coding sequences in which all three nuclear localization signals have been mutated. NLS1 and NLS2 have been altered using site directed mutagenesis (amino acid replacements R159A, K160A, K162A and K237A, K238A, R240A respectively) and NLS3 has been truncated. A nuclear export sequence (Tag:NES(Unk)) has been added to both the N-terminal and C-terminal ends of the protein, and it is tagged at the N-terminal end with Venus.