Western blot was performed using anti-UBC13 Polyclonal Antibody (Product # PA5-20080) and a 17 kDa band corresponding to UBE2N was observed across all the cell lines and tissues tested. Whole cell extracts (30 µg lysate) of A431 (Lane 1), HepG2 (Lane 2), HeLa (Lane 3), NIH:OVCAR-3 (Lane 4), BeWo (Lane 5), HL60 (Lane 6), MOLT-4 (Lane 7), tissue extracts of Mouse Testis (Lane 8), Mouse Brain (Lane 9), Mouse Liver (Lane 10) and Mouse Ovary (Lane 11) were electrophoresed using NuPAGE™ 4-12% Bis-Tris Protein 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 (1:1000 dilution) and detected by chemiluminescence with Goat anti-Rabbit IgG (Heavy Chain) Superclonal™ Recombinant Secondary Antibody, HRP (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).