In termination, what binds to the stop codon to cleave the polypeptide?

In termination, what binds to the stop codon to cleave the polypeptide?

• A. Ribosome
• B. tRNA
• C. mRNA
• D. Release factor

Answer: (D)

During translation termination, the stop codon in the ribosome’s A site is recognized not by a tRNA, but by a release factor. This protein binds the stop codon and then catalyzes the hydrolysis of the bond linking the growing polypeptide to the tRNA in the P site, freeing the new protein. In bacteria there are different release factors that recognize specific stop codons, while in eukaryotes a single release factor recognizes all stop codons with help from another factor. After the polypeptide is released, the ribosome and its components dissociate to begin new rounds of translation.

During translation termination, the stop codon in the ribosome’s A site is recognized not by a tRNA, but by a release factor. This protein binds the stop codon and then catalyzes the hydrolysis of the bond linking the growing polypeptide to the tRNA in the P site, freeing the new protein. In bacteria there are different release factors that recognize specific stop codons, while in eukaryotes a single release factor recognizes all stop codons with help from another factor. After the polypeptide is released, the ribosome and its components dissociate to begin new rounds of translation.