Two-hybrid system. A phosphomimetic version of smo, with PKA site Ser residues mutated to Asp, was used as bait in the two-hybrid screen.

Source was yeast cell line; bait produced as transgenic fusion protein; prey produced as transgenic fusion protein (prey from embryo cDNA expression library).

Hyperphosphorylation of smo upon treatment with hh, as inferred by change in electrophoretic mobility, is associated with reduction of its interaction with smg.

Source was cell extract of Cl8 cell line; bait produced from transfected construct; prey produced from transfected construct.

Source was S2R+ cells; bait and prey produced from transfected construct.

Bait protein was fused to plasma membrane anchor. The ability of this chimera to recruit prey protein to the plasma membrane was taken as evidence of direct physical interaction.

Source was S2R+ cells; bait and prey produced from transfected construct.

Bait protein was fused to plasma membrane anchor. The ability of this membrane bound bait to recruit prey protein to the plasma membrane was taken as evidence of direct physical interaction.

Source was S2R+ cells; bait and prey produced from transfected construct.

Bait protein was fused to plasma membrane anchor. The ability of this chimera to recruit prey protein to the plasma membrane was taken as evidence of direct physical interaction.

Interaction in vitro; smg produced as a recombinant fusion proteins in bacterial system; smo peptide chemically synthesized.

Two strategies were pursued for crystallization: one in which Smaug 70-281 δ156-196(His tag removed) was mixed with a Smo 970- 1003 peptide and a second in which the Smo 970-1003 sequence was fused to the N terminus of Smaug 73-278 δ156-196 using a (GGS)4 linker with similar results.