FIG. 7.

Interaction between PRC and NRF-1 in vivo. (A) Coimmunoprecipitation of PRC and NRF-1 from cell extracts. C2C12 myoblast whole-cell extracts (750 μg) were subjected to immunoprecipitation using either anti-PRC serum (lane 1) or preimmune serum (lane 2). Immune complexes were brought down with protein A-agarose, washed, and run on an SDS–7.5% PAGE gel. As positive controls, 50 μg of the extract and 3 ng of the recombinant NRF-1 were run in lanes 3 and 4, respectively. After transfer, the immunoblot was probed with affinity-purified goat anti-NRF1 antibody. Molecular mass standards in kilodaltons are indicated on the right. (B) Colocalization of PRC and NRF-1 by confocal laser scanning fluorescence microscopy. BALB/3T3 cells transfected with NRF-1–3xHA were stained with anti-PRC serum (green) (a) or anti-hemagglutinin antibody (red) (b). Green and red images were merged (panel c) to visualize nuclear colocalization. Panel dimensions are 66.5 by 66.5 μm. Confocal images were generated with an LSM 510 confocal microscope (Zeiss).