Figure 5.

Association of WRN with components of the core Pol δ enzyme in vivo. (A) Separate nucleoplasmic (N) and nucleolar (NS) fractions were prepared and immunoprecipitated with normal mouse IgG as control (C) or anti-WRN (WRN) monoclonal antibody. The precipitates were analyzed by Western blotting using anti-p50 antibody (Middle, lanes 1–4). The same blot was reprobed by anti-p125 polyclonal antibody (Top). The bottom panel indicates the respective unprocessed extracts probed with anti-p50 (input, lanes 1–4). (B) Combined nuclear and nucleolar extracts from HeLa cells were immunoprecipitated with normal mouse IgG (C) or anti-WRN monoclonal antibody (WRN) and analyzed by Western blotting with a monoclonal antibody against human PCNA (lanes 1 and 2). Pre-IP inputs for the respective immunoprecipitates are indicated (lanes 3 and 4).