Figure 1

Grb14 is tyrosine phosphorylated in the presence of Tie2. 293T kidney epithelial cells were transfected with Grb14 either alone or with the wild type receptor (Tie2) or a kinase inactive mutant of Tie2 (K853A). Cell lysates from these transfections were then subjected to immunoprecipitation using an anti-Grb14 antibody and blotted for phospho-tyrosine (4G10) or anti-FLAG to check for Grb14 amount precipitated.