FIG. 4.
Characterization of antibodies. (A) Anti-C147 antibodies from rabbits, which were affinity purified with GST-C147 that contained the C-terminal 147 amino acids of Xenopus NBS1, were immunoblotted with Xenopus egg extract. In addition to Nbs1, a larger-molecular-weight protein (indicated by an asterisk) was also recognized by anti-C147. (B) Anti-C50 antibodies from rabbits, which were affinity purified with GST-C50 that contained the C-terminal 50 amino acids of Xenopus NBS1, were immunoblotted with Xenopus egg extract. (C) Egg extract was treated with control IgG or anti-C147 to immunodeplete Nbs1. Following depletion, extracts were immunoblotted with anti-C147. Depletion of Nbs1 from the extract using anti-C147 removed Nbs1 but not the larger protein shown in panel A. (D) Anti-ATM antibodies were generated in rabbits using GST-XATMC containing the C-terminal 300 amino acids of Xenopus ATM. These antibodies were affinity purified with His-GFP-XATMC and immunoblotted with Xenopus egg extract. (E) Shown is an immunoblot of Xenopus egg extract and HeLa cell lysate with anti-Mre11 antibodies purchased from Oncogene Research Products.