Western blot was performed using Phospho-Rb (Ser807) Recombinant Rabbit Monoclonal Antibody (SR3-82) (Product # MA5-32005) and a 106 kDa band corresponding to Phospho-Rb along with an uncharacterized (*) band ~70 kDa was observed across treated panels. Nuclear enriched extracts (40 µg lysate) of LNCaP (Lane 1), LNCaP treated with Nocodazole (83 nm, 24 hours) (Lane 2), K-562 (Lane 3), K-562 treated with Nocodazole (83 nm, 24 hours) (Lane 4) were electrophoresed using NuPAGE™ 4-12% Bis-Tris Protein Gel (Product # NP0321BOX), 10 well. Resolved proteins were then transferred onto a nitrocellulose membrane (Product # IB23001) by iBlot® 2 Dry Blotting System (Product # IB21001). The blot was probed with the primary antibody (1:1000 dilution) and detected by chemiluminescence with Goat anti-Rabbit IgG (Heavy Chain) Superclonal™ Recombinant Secondary Antibody, HRP (Product # A27036, 1:20,000 dilution) using the iBright™ FL1500 Imaging System (Product # A44115). Chemiluminescent detection was performed using SuperSignal™ West Dura Extended Duration Substrate (Product # 34076), LNCaP cells were exposed for 45 seconds while K-562 cells were exposed for 5 seconds.

Immunocytochemical analysis of Phospho-Rb (Ser807) in MCF-7 cells using a Phospho-Rb (Ser807) Monoclonal antibody (Product # MA5-32005) as seen in green. The nuclear counter stain is DAPI (blue). Cells were fixed in paraformaldehyde, permeabilised with 0.25% Triton X100/PBS.