UASt regulatory sequences drive expression of smo coding sequences fused with a non-fluorescent split fluorescent protein fragment (N-YFP, amino acids 1-173 of YFP). Designed to be used in a bimolecular fluorescence complementation (BiFC) assay; if N-YFP protein is placed in proximity to a complementary split fluorescent protein fragment, a functional fluorescent protein may be reconstituted, allowing this to be used as an assay for protein interactions in vivo. The protein is also tagged with the Tag:MYC epitope.