FIG. 6.

Selective depletion of inhibitory proteins in HeLa cell nuclear extracts with ESSV RNA-beads. (A) Samples (50 μg) from nondepleted nuclear extracts and nuclear extracts depleted with either ESSV or ESSVx paramagnetic bead-immobilized RNAs were separated by SDS–10% PAGE and stained with Coomassie blue. Circles on the right indicate differences between the ESSV RNA-beads and the ESSVx RNA-beads. Apparent molecular weights (in thousands) are shown on the left. (B) Western blot analyses of proteins in depleted and nondepleted extracts were carried out with the indicated anti-hnRNP antibodies as described in Materials and Methods. For the analyses with anti-hnRNP A1 and anti-hnRNP B1 antibodies, 20 μg of protein from the depleted or nondepleted extracts was analyzed. For the analysis with anti-hnRNP A2 antibody, 50 μg of protein from the depleted or nondepleted extracts was analyzed. The anti-hnRNP A2 antiserum also detects hnRNP A1. (C) Aliquots (1 to 8 μl) from HeLa cell nuclear extracts (HNE) nondepleted or depleted with either wild-type (ESSV) or mutant (ESSVx) RNA bound to beads were electrophoresed, and Western blot analysis was carried out using anti-hnRNP A1 antibody.