FIGURE 1.

Two-hybrid analysis of srGAP2 SH3 domain interactions. A, a schematic shows the fragment of FMNL3 identified in the library screen using the srGAP2 SH3 domain bait. Amino acid positions are indicated for each. B, specificity of the srGAP2 and FMNL3 interaction was verified in the two-hybrid assay. Yeast containing clone 24 and either empty vector (negative control), srGAP2 SH3, WRP SH3, Nck SH3, or profilin (positive control) were plated onto plates lacking uracil, tryptophan, and leucine (−UWL) or also histidine and lysine (−WHULK). Although all yeast could grow on the −UWL plate, indicating the yeast contain both bait and prey vectors, only the srGAP2 and profilin containing yeast grew on the −WHULK plates, confirming an interaction. Yeast were also assayed for β-galactosidase activity (LacZ), which further confirmed srGAP2 SH3 is specific for FMNL3. DD stands for dimerization domain.