Fig. 5. The enhancement of ubiquitylation of Dock180 by Crk. An in vivo ubiquitylation assay was performed using lysates of the membrane fraction of HEK293T cells expressing the indicated plasmids (left panels). The IP ratio represents the relative signal intensity of immunoprecipitated Dock180 in lane 1 as 1.0 (bottom of the left panel). The expression levels of Dock180, Crk I and Crk II in the membrane fraction of cell lysates (membrane) and in total cell lysates (total) were determined by immunoblotting (right upper and middle panels). Anti-E-cadherin antibody was used as a marker for the membrane fraction (right lower panel).