Fig. 9. Co-sedimentation of Sp1 and Sp3 with F-actin. MCF-7 nuclear extract was mixed with G-buffer and polymerization inducer (lanes 1 and 2), G-actin (lanes 3 and 4) or F-actin (lanes 5 and 6). BSA was added as negative control. Mixtures were spun. Pellet (lanes 1, 3 and 5) and supernatant (lanes 2, 4 and 6) fractions were resolved by SDS-PAGE. Sp1 and Sp3 were detected by western blot (WB), whereas BSA and actin were visualized by Coomassie Blue (CB) staining