UASt regulatory sequences drive expression of full-length Scr in which the sixth and seventh residues of the homeodomain have been mutated from TS to DD and also containing the mutation E19G. The protein is tagged at the N-terminal end with C-Venus, a non-fluorescent split fluorescent protein fragment. Designed to be used in a bimolecular fluorescence complementation (BiFC) assay to study protein-protein interactions in vivo.