FIG. 5.

Analysis of polysome profiles from gcd6 mutant yeast strains using low-salt sucrose density gradient centrifugation. (A) Extracts prepared from cells grown in YPD medium at 30°C were centrifuged on low-salt 7 to 47% sucrose gradients. Gradients were fractionated while scanning at 254 nm, and the resulting profiles are shown. The positions of ribosomal subunits, 80S monosomes, and polysomes are indicated. The ratio of polysomes to 80S monosomes was determined by measuring the area under the peaks using NIH Image software. (B) Extracts from the same yeast strains were centrifuged on low-salt 15 to 35% sucrose gradients. This provides greater separation of the top portion of the gradient. Proteins collected in fractions from the gradients were analyzed by SDS-PAGE and Western blotting using the antisera indicated to the right.