tRNA, or transfer RNA, contains two functional regions. One region is the anticodon—a sequence of three nucleotides that corresponds to the coding region of an mRNA molecule. The anticodon-codon sequences define the identity of the amino acid coded for by that particular region of the gene. The second functional region of tRNA is bound to the amino acid that corresponds to the particular anticodon-codon sequence. tRNA will transport this amino acid to a ribosome, bind to the codon on the mRNA, and release the amino acid for incorporation into the growing polypeptide.

The Shine-Dalgarno sequence is located just upstream of the start codon on a strand of prokaryotic RNA. The sequence functions to bind the rRNA of the ribosome, recruiting it to the proper location to initial translation.