Colocalization of tyrosine phosphorylated cortactin and active Src at focal adhesions. Bar, 10 μm. (A) Colocalization of cortactin, Src and actin at the lamellipodial edge. COS7 cells were fixed with paraformaldehyde and Triton X-100, and stained with anti-cortactin antibody (Cttn), anti-Src antibody (Src), phalloidin (pha) and DAPI (DAPI). M, the merged picture; stag., the staggered picture. X2, 2 times enlargement. (B) The lamellipodial edge stained with an anti-cortactin (Cttn) or an anti-Tyr421-phosphorylated cortactin (pCttn) antibody. (C) Colocalization of Tyr421-phosphorylated cortactin (pCttn) and Tyr418-phosphorylated Src (pSrc) at focal contacts at the lamellipodial edge. Pax, anti-paxillin antibody staining. (D) Colocalization of Tyr421-phosphorylated cortactin and Tyr418-phosphorylated Src at focal adhesions. (E) The immunofluorescence staining of Tyr421 or 466-phosphorylated cortactin. COS7 cells expressing exogenous EGFP-tagged cortactin (GFP-Cttn) were stained with anti-phosphotyrosine421 or anti-phosphotyrosine466 antibody (pCttn421, pCttn466).