Western blot was performed using Anti-Bub3 Polyclonal Antibody (Product # PA5-20388) and 37 kDa band corresponding to Bub3 was observed across cell lines and tissues tested along with certain uncharacterized bands at ~60 and ~110 kDa. Modified whole cell extracts (1% SDS) (30 µg lysate) of HeLa (Lane 1), A549 (Lane 2), A-431 (Lane 3), Hep G2 (Lane 4), PC-3 (Lane 5), HEK-293 (Lane 6), Jurkat (Lane 7), SK-BR-3 (Lane 8), tissue extracts of Mouse Brain (Lane 9) and Mouse Spleen (Lane 10) were electrophoresed using Novex® NuPAGE® 4-12 % Bis-Tris gel (Product # NP0322BOX). 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 (0.5 µg/mL) and detected by chemiluminescence Goat Anti-Rabbit IgG Secondary Antibody, HRP conjugate (Product # A27036, 1:4000 dilution) using the iBright FL 1000 (Product # A32752). Chemiluminescent detection was performed using Novex® ECL Chemiluminescent Substrate Reagent Kit (Product # WP20005).