Similar changes in pre-60S subunit protein composition occur upon depletion of the B-factors Dbp10, Nog1, Spb4, or Nog2. The TAP-tagged AF Nop7 was used as bait to purify pre-60S subunits from yeast expressing (gal) or depleted of (glu) the B-factors Dbp10, Nog1, Spb4, and Nog2. The preribosome protein composition was analyzed by SDS-PAGE followed by silver staining (A) and Western blotting for AFs (B) and r-proteins (C). Asterisks indicate that the protein being blotted for was tagged and detected with anti-HA antibody.