FIG. 7.

Localization of Fes to MTs requires a functional SH2 domain. COS-7 cells were transfected with expression plasmids for wild-type GFP-Fes (WT), kinase-active GFP-Fes (L145P), or active Fes with a Leu substitution of Arg 483 in the SH2 domain phosphotyrosine binding pocket (LP-RL). (A) Transfected cells were visualized by GFP fluorescence, and digital images were recorded. (B) Cells from each transfection condition were examined for the appearance of MT-like localization of each GFP-Fes protein. At least 150 cells were counted for each condition. The results are presented as the mean plus standard deviation of three separate experiments. (Bottom) Immunoblots from transfected cell lysates showing phosphotyrosine content of GFP-Fes proteins (pTyr; top) and relative expression levels using a GFP antibody (Fes; bottom). The positions of the GFP-Fes proteins are indicated by the arrows.