▶ Protein Synthesis Animation Video - 2:25 tRNA is joined to the mRNA by a peptide bond. A tRNA moved into the Asite where the codons match the mRNA the Ribosome shifts down by one codon at a time and new amino acids are added one at a time. It cuts off when a stop codon moves into the A site on the mRNA. The mRNA & the amino acid/protein are both released by the ribosome. p-site, A (acceptor) site & E site =Exit
The Shine-Dalgarno element in prokaryotic RNAs The Shine-Dalgarno (SD) sequence is a ribosomal binding site in prokaryotic messenger RNA, generally located around 8 bases upstream of the start codon AUG. The RNA sequence helps recruit the ribosome to the mRNA to initiate protein synthesis by aligning the ribosome with the start codon.