FIG. 1.—

Effects of wrong tRNA anticodon–mRNA codon association on protein translation. (A) Canonical translation of protein (yellow polygon): Optimal codon (yellow vertical bars) efficiently recognizes tRNA (in yellow) with correct amino acid (yellow circle). Right polypeptide is produced (yellow stripe) and properly folded (yellow polygon). (B) Codon is not optimal (yellow vertical bars plus red bar); then wrong tRNA (in red) can be recruited; an uncorrected amino acid (red cross) is inserted in nascent polypeptide (chain in yellow and gray). A misfolded protein is produced (gray and red polygon) and may undergo degradation (in gray) but, if it does not, it can interact with cell structures.