Fig. 3
From: The phosphatase Shp1 interacts with and dephosphorylates cortactin to inhibit invadopodia function
Shp1 interacts with cortactin. A Interaction between Shp1 and cortactin was examined by immunoprecipitation with an anti-Shp1 antibody (IP) in A375MM cells plated on gelatin-coated Petri dishes. The expression levels of Shp1 and cortactin were examined in total lysates (input). B, C Representative immunoprecipitated cortactin fraction (IP: Flag-cortactin) from A375MM cell lysates washed and incubated with purified recombinant Shp1 for the indicated time points at 37 °C in the absence (−) or presence (+) of 5 mM Na3VO4 (as indicated). The tyrosine-phosphatase inhibitor Na3VO4 was used as negative control. The top panels show western blot analyses with an anti-pY421-cortactin (B) and anti-pY470-cortactin (C) antibodies to reveal the specific phosphorylation of tyrosine residues in cortactin. The blots were then re-probed with an anti-cortactin antibody for immunoprecipitated proteins (middle panels). The lower panels show purified recombinant Shp1 added in each sample. Molecular weight standards (kDa) are indicated on the left of each panel. IgGH, IgG heavy chain; IP, immunoprecipitation