Western blot analysis was performed on whole cell extracts (30 µg lysate) of COLO 205 (Lane 1) and COLO 205 treated with Nocodazole (3 uM for 24 hrs) (Lane 2). The blots were probed with Anti-Rb (pS788) Recombinant Rabbit Polyclonal Antibody (Product # 711143, 1-2 µg/mL) and detected by chemiluminescence using Goat anti-Rabbit IgG (Heavy Chain) Superclonal™ Secondary Antibody, HRP conjugate (Product # A27036, 0.4 µg/mL, 1:2500 dilution). A 110 kDa band corresponding to Rb (pS788) was observed. To confirm the specificity of Anti-Rb (pS788) Recombinant Rabbit Polyclonal Antibody, competition was performed with the phosphopeptide (10 µg/mL) as shown in the corresponding blot on the right. The phosphopeptide competes with the antibody and prevents it from binding to the target protein. Known quantity of protein samples were electrophoresed using Novex® NuPAGE® 4-12% Bis-Tris gel (Product # NP0321BOX), XCell SureLock™ Electrophoresis System (Product # EI0002) and Novex® Sharp Pre-Stained Protein Standard (Product # LC5800). Resolved proteins were then transferred onto a nitrocellulose membrane with iBlot® Dry Blotting System (Product # IB21001). The membrane was probed with the relevant primary and secondary Antibody following blocking with 5% skimmed milk. Chemiluminescent detection was performed using Pierce™ ECL Western blotting Substrate (Product # 32106).