All lanes : Anti-Src (phospho Y215) antibody ( ab24789 ) Lane 1 : A431 cells treated with pervanadate (1 mM) for 30 minutes (20 µg/lane) with no blocking peptide Lane 2 : A431 cells treated with pervanadate (1 mM) for 30 minutes (20 µg/lane) with phospho-c-Src (Tyr-215) peptide (ab42782) at 1ug/ml. Lane 3 : A431 cells treated with pervanadate (1 mM) for 30 minutes (20 µg/lane) with unrelated phospho-ß-Catenin (Tyr-142) peptide at 1ug/ml. Lane 4 : A431 cells treated with pervanadate (1 mM) for 30 minutes (20 µg/lane) with BSA conjugated to phospho-tyrosine at 1ug/ml.