What are the different mechanisms for quality control?
Answers
Translation uses the genetic information in messenger RNA (mRNA) to synthesize proteins. Transfer RNAs (tRNAs) are charged with an amino acid and brought to the ribosome, where they are paired with the corresponding trinucleotide codon in mRNA. The amino acid is attached to the nascent polypeptide and the ribosome moves on to the next codon. The cycle is then repeated to produce a full-length protein. Proofreading and editing processes are used throughout protein synthesis to ensure the faithful translation of genetic information. The maturation of tRNAs and mRNAs is monitored, as is the identity of amino acids attached to tRNAs. Accuracy is further enhanced during the selection of aminoacyl-tRNAs on the ribosome and their base pairing with mRNA. Recent studies have begun to reveal the molecular mechanisms underpinning quality control and go some way to explaining the phenomenal accuracy of translation first observed over three decades ago.