eIF3f regulates the recruitment of translational proteins to the mRNA 7-methylguanosine cap structure.

(A) Binding of translational components to the 7-methylguanosine cap complex is enhanced by eIF3f. Mouse primary cultured satellite cells were transfected with expression vectors encoding HA-tagged eIF3f wt and/or the mutant eIF3f K_5–10R and differentiated for 3 days. Cap-binding proteins in lysates were purified by 7-methyl GTP (m⁷GTP) affinity beads. Levels of proteins and phosphoproteins were analyzed by Western blotting. (B) eIF3f silencing leads to decreased recruitment of translational components to the m⁷-GTP cap complex. Mouse primary cultured satellite cells were subjected to RNAi-mediated silencing of eIF3f using specific small hairpin RNA. A nonspecific shRNAi was used as control. Cell lysates were purified by m7-GTP and analyzed as described in (A).