UAS regulatory sequences drive expression of smo which carries both phospho-mimetic mutations in the three PKA/CK1 phosphorylation sites (SD123) and also contains mutations in the 'CL-II' Ser/Thr cluster in the juxtamembrane region of the C-terminal intracellular tail (amino acid replacements S626A, S627A, S633A and S634A). The protein is tagged with CFP.