FIG. 6.

5′-3′ cyclization is not required for cHP-mediated start codon selection. (A) Schematic diagram of constructs used to test the impact of potential 5′-3′ cyclization on initiation site selection. (B) Anti-FLAG immunoblot of C-FLAG-transfected Hep3B cells at 4 h posttransfection. The efficiency of codon usage is expressed as a ratio of the higher-molecular-weight C-FLAG isoform (1st AUG) to the lower-molecular-weight isoform (2nd AUG). The data are derived from three experiments. (C) Anti-FLAG immunoblot of transfected C6/36 cells at 24 h posttransfection as in panel B. The table is as in panel B; the data represent the averages of three experiments.