npg Fused dimerization transduces Hedgehog signal 1450 mRNA level normalization [47]. Transgenes Transgenic lines were generated using pUAST vector by stan- dard P-element mediated transformation and were as follows: UAS-Fu-CFPC, UAS-Fu-YFPC, UAS-Smo-CFPC [17], UAS-Cos2- CFPC, UAS-Cos2-YFPC, UAS-Div, UAS-Div-Fu, UAS-Div-FuK, UAS-Div-FuK*, UAS-Div-FuG13V, UAS-Div-FuKG13V and UAS-Div-FuK*G13V. Fu-G13V corresponds to a substitution of Gly 13 by Val within Fu catalytic domain. Multiple independent transgenic lines were tested for activity. MS1096, dpp-lacZ, Ptc- Gal4 and AG-Gal4, dpp-lacZ have been described [9]. Acknowledgments We thank Dr Jin Jiang (University of Texas Southwestern Med- ical Center at Dallas, USA), Dr Robert Holmgren (Northwestern University, USA), the ARIAD Pharmaceuticals and Developmen- tal Studies Hybridoma Bank at the university of Iowa for reagents. 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