Final answer:
Translation termination requires release factors upon the ribosome encountering a stop codon (UAA, UAG, or UGA). These factors promote the release of the new polypeptide and the dissociation of the ribosomal subunits.
Step-by-step explanation:
The termination of translation in protein synthesis requires the presence of release factors. This process occurs when a stop codon (UAA, UAG, or UGA) on the mRNA is encountered by the ribosome. The release factors, primarily RF1, RF2, and RF3, recognize the stop codon in the A site of the ribosomal complex. These factors then promote the hydrolysis of the bond between the terminal amino acid and its tRNA, leading to the release of the newly synthesized polypeptide chain and the tRNA from the P site. Finally, they facilitate the dissociation of the ribosomal subunits, thus ending the process of protein synthesis. Unlike other steps throughout this process, there is no involvement of a terminator tRNA, as no tRNA can recognize the stop codons. Moreover, the E site is involved in releasing deacylated tRNAs during the elongation phase, not in the termination phase directly.