What is the function of release factors during translation termination?

• A. Release factors facilitate tRNA charging.
• B. Recognize stop codons in the A site and promote hydrolysis of the polypeptide from the tRNA, releasing the completed protein and dissociating ribosome.
• C. Release factors promote peptide bond formation.
• D. Release factors cause ribosome to reinitiate translation.

Answer: (B)

Release factors play the key role in translation termination. They recognize stop codons in the A site and trigger the hydrolysis of the bond between the growing polypeptide and the tRNA in the P site. This reaction releases the completed protein from the ribosome. Afterward, the ribosome dissociates and recycling proceeds so the components can be reused for another round of translation. This differs from tRNA charging, which is done by aminoacyl-tRNA synthetases, and from peptide bond formation, which is the job of the peptidyl transferase during elongation. Release factors do not drive reinitiation.