Supplement Figure 2 HEK 293 cells Supplement Figure 2. RET/PTC-mediated XB130 phosphorylation and AKT-activation were independent of Src kinase activity. A) HEK293 cells were co-transfected with XB130-myc and RET/PTC3 with or without a dominant negative mutant of SrcK- (Src YFKM). Immunoprecipitation of XB130 using a myc antibody was followed by western blotting with anti-myc and anti-phosphotyrosine (pY) antibodies. Total lysates were also blotted with RET and Src antibodies. B) Same cell lysates as in (A) were electrophoresed and blotted for total and phosphorylated form of Akt.