Which one of the following options represents parts of a tRNA that are involved in amino acid charging and interaction with the mRNA, respectively?
3' end and anti-codon loop
tRNA Structure and Function
Transfer RNA (tRNA) molecules are essential components of the protein synthesis machinery in cells. Each tRNA molecule acts as an adaptor, carrying a specific amino acid and recognizing a corresponding codon on the messenger RNA (mRNA) molecule.
tRNA Amino Acid Charging
Amino acid charging, also known as aminoacylation, is the process where a specific amino acid is attached to its corresponding tRNA molecule. This crucial step is catalyzed by enzymes called aminoacyl-tRNA synthetases.
The site on the tRNA molecule where the amino acid is attached is the 3' end. Specifically, the amino acid is covalently linked to the 3'-hydroxyl group of the terminal adenosine residue at the acceptor stem of the tRNA. This makes the tRNA "charged" or "aminoacylated", ready to participate in translation.
tRNA Interaction with mRNA
The interaction between tRNA and mRNA occurs during translation on the ribosome. The tRNA molecule recognizes a specific sequence of three nucleotides on the mRNA, called a codon.
This recognition is mediated by a specific region on the tRNA molecule called the anti-codon loop. This loop contains a sequence of three nucleotides known as the anticodon. The anticodon is complementary to the codon on the mRNA molecule, and they pair through hydrogen bonds (Watson-Crick base pairing or wobble pairing).
This codon-anticodon interaction ensures that the correct amino acid is delivered to the growing polypeptide chain according to the sequence dictated by the mRNA.
Summary of tRNA Parts and Functions
Based on the functions discussed:
- The part of tRNA involved in amino acid charging is the 3' end (acceptor stem).
- The part of tRNA involved in interaction with the mRNA is the anti-codon loop.
Therefore, the option that correctly represents these two parts, respectively, is "3' end and anti-codon loop".
Important Questions from Protein synthesis and processing
Many organisms encode only 18 aminoacyl-tRNA synthetases (aaRS). These organisms lack aaRS that use Asn or Gln (as one of the substrates) for direct aminoacylation of the tRNAAsn and tRNAGln, respectively. Which one of the following statements represents the correct option?
Precise recognition of tRNAs by their cognate aminoacyl‐tRNA synthetases is crucial for the fidelity of protein synthesis. In the context of the aminoacylation of tRNAAla with its cognate aminoacyl‐tRNA synthetase (AlaRS) and based on the studies on the molecules of Escherichia coli origin, following statements are made. Which one of the statements is INCORRECT?
Which one of the following RNAs possesses the peptidyltransferase activity?
Which one of the following statements about GAL gene expression is FALSE?
In Trypanosoma, some of the introns generate Y shaped structure in place of a lariat. Such structure is generated during
