Western blot analysis of extracts from HeLa cells untransfected (lane 1) or transfected with p73 DNA (lanes 2 and 3). Overexpression of p73 can be specifically blocked by co-transfection with p73 siRNA #6371 (lane 3). p73 was detected using p73 Antibody and p42 was detected using p42 MAPK Antibody #9108. The p73 Antibody confirms silencing of exogenous p73 expression and the p42 MAPK Antibody is used to control for loading and siRNA specificity.