All lanes : Anti-Src (phospho Y215) antibody (ab24789) at 1/1000 dilutionLane 1 : A431 cells treated with pervanadate (1 mM) for 30 minutes (20 ug/lane) with absence of blocking peptideLane 2 : A431 cells treated with pervanadate (1 mM) for 30 minutes (20 ug/lane) with presence of phospho-c-Src (Tyr-215) peptide Lane 3 : A431 cells treated with pervanadate (1 mM) for 30 minutes (20 ug/lane) with presence of unrelated phospho-beta-Catenin (Tyr-142) peptideLane 4 : A431 cells treated with pervanadate (1 mM) for 30 minutes (20 ug/lane) with BSA conjugated to phospho-tyrosine