Question

Which loop in tRNA recognizes the aminoacyl synthetase enzyme?

• A. Anticodon loop
• B. TѰC loop
• C. DHU loop
• D. Amino acid acceptor arm

Answer 1

The correct option is C

DHU loop

The correct option is C.

Explanation of the correct option:

1. The group of enzymes known as aminoacyl-tRNA synthetases is responsible for attaching amino acids to transfer RNAs (tRNAs).
2. Aminoacyl-tRNA synthetases activate the amino acids by covalently linking them to tRNAs during the process of translation.
3. DHU Loop or the D loop of the tRNA is composed of 7-11 bases and is closed by a Watson crick base pair.
4. The D loop contains the modified nucleotide dihydrouridine.
5. The recognition process is the primary purpose of the D loop. It serves as a recognition site for the enzyme aminoacyl-tRNA synthetase.
6. Dihydrouridine recognizes aminoacyl-tRNA synthetase enzymes.

Explanation of the incorrect options:

Option A:

1. The nucleotides of the anticodon loop on tRNA are complementary to the code.
2. The amino acid acceptor end binds to amino acids. Every amino acid has its own set of tRNAs.

Option B:

1. T-arm or T-loop of tRNA binds to the ribosome during protein synthesis.
2. Because thymidine, cytidine, and pseudouridine are present in this loop, it is known as TѰC.

Option D:

1. The 3' end of t-RNA is the amino acid acceptor arm.
2. The ester bond attaches the amino acid to the 3' end based on the mRNA sequence read by the anticodon loop.

Final answer: DHU loop recognizes the aminoacyl synthetase enzyme.