Knockdown of PCAF was achieved by transfecting LNCaP cells with PCAF specific validated siRNA (Silencer® select Product # s16894). Western blot analysis (Fig a) was performed using modified whole cell extracts (1% SDS) from PCAF knockdown cells (Lane 3), non-specific scrambled siRNA transfected cells (Lane 2) and untransfected cells (Lane 1). The blot was probed with Anti-PCAF Recombinant Rabbit Monoclonal Antibody (Product # 703379, 1:500 dilution) and Goat anti-Rabbit IgG (H+L) Superclonal™ Secondary Antibody, HRP conjugate (Product # A27036, 0.25 µg/mL, 1:4000 dilution). Densitometric analysis of this Western blot is shown in the histogram (Fig b). Loss of signal upon siRNA mediated knockdown confirms that antibody is specific to PCAF.