Protein Synthesis and Ribosomal Proofreading Mechanism
What is the role of ribosomes in proofreading amino acids during protein synthesis?
Which of the following statements regarding the ability of ribosomes to proofread amino acids attached to tRNA is true?
a) Ribosomes have proofreading enzymes.
b) Ribosomes do not proofread.
c) Ribosomes rely on tRNA proofreading.
d) Ribosomes only proofread in eukaryotes.
Answer:
Ribosomes rely on tRNA proofreading during translation. The match between the mRNA codon and tRNA anticodon helps ensure the correct amino acid is added to the growing protein chain. This acts as a form of proofreading but it's not foolproof, and errors can still occur.
In the process of protein synthesis known as translation, the correct statement about ribosomes' ability to proofread amino acids attached to tRNA is that ribosomes rely on tRNA proofreading (option c). However, this is not a direct process, but relies on the correct base pairing between the mRNA codons and the tRNA anticodons. The process begins when ribosomes read the mRNA template and the tRNA brings the corresponding amino acids to the building protein chain. Each tRNA molecule has a specific anticodon on one end and a binding site for a specific amino acid on the other. It is this specific match between the mRNA codon and tRNA anticodon that helps ensure the correct amino acid is added to the growing protein chain. If there is a mismatch, the tRNA will not fit properly and this helps to provide a proofreading mechanism. However, this proofreading is not foolproof and errors can still occur, potentially leading to dysfunctional or harmful proteins.
Understanding the intricate process of protein synthesis and the role of ribosomes in proofreading ensures the correct translation of genetic information into functional proteins. This mechanism highlights the precision and complexity of cellular processes that are essential for proper functioning and survival of living organisms.