Figure 5.

Association of subunits of the APC ubiquitin ligase with the proteasome. Extracts from strains with the indicated genotypes were immunoprecipitated with anti-Flag resin in the absence of ATP. Bound proteins were eluted from the resin with either SDS (A) or flag peptide (B). Eluates were resolved by SDS-PAGE and immunoblottted with biotinylated monoclonal antibody to the HA epitope (A) or HRP-conjugated monoclonal antibody against the myc epitope. In B, L refers to crude extract used for immunoprecipitation (“load,” 0.2% of the bound), and E refers to the eluate (4% of total).