Figure 6.

Hax-1 is associated with cortactin. (a and b) COS-7 cells were transiently transfected with various combinations of expression plasmids coding for myc-tagged cortactin, a GST/Hax-1 fusion protein and GST only. Protein extracts from transfected cells were used for immunoprecipitation with an anti-myc-epitope antibody and for GST pull-down assays (Prec.). The precipitates then were analyzed by Western blot with an anti-GST (a) and anti-myc-epitope antibody (b) (Blot). In either case cortactin and Hax-1 are coprecipitated, demonstrating an association between the two proteins. (c) Stably transfected HeLa cells constitutively expressing a GST/Hax-1 fusion protein were double-stained with a mouse mAb against GST (Upper) and a rabbit polyclonal antibody against cortactin (Lower). It can be easily seen that the two proteins colocalize in lamellipodia (arrows).