FIG 2.

RACK1 binding to the ribosome is necessary for modulating translation. (A) Representative Coomassie blue-stained gel showing purified MBP-RACK1 proteins prior to MBP cleavage. wt, wild type; mut, mutant. (B) Efficiencies of binding of recombinant proteins (MBP [used as a control], wild-type RACK1, and R36D K38E mutant RACK1) to the ribosome as measured by an in vitro ribosome interaction assay. (C) Quantification of in vitro translational efficiencies of different mRNAs under conditions of RACK1 depletion that were rescued by recombinant wild-type or mutant RACK1 proteins. Data are from representative assays. At least four independent replicates per experiment were performed. Means and standard deviations are shown. Statistical significance was determined by the t test. P values are indicated as follows: *, <0.05; **, <0.01; ***, <0.001.