ESAT-6 stimulated increase in the phosphatase activity associated with ERK1/2 in the nucleus. (A) RAW264.7 cells were stimulated for different time points of 0, 15, 30, 60 and 120 minutes, the ERK-1 was immunoprecipitated from the nuclear extract and the phosphatase activity was determined, the last column where cells were stimulated with ESAT-6 for 120 minutes but no ERK-1 antibody was added (antibody control). (B) After phosphatase assay was done, the immunoprecipitate was mixed with 2× sample buffer and run on 10% SDS-PAGE and after western blotting the membrane was probed with ERK-1 antibody to confirm equal pull down of ERK1/2 in all the samples. The graph shows the mean +/- S.D. of three independent experiments.