Which one or more of the following statements correctly describe(s) the addition of N-nucleotides during the rearrangement of the immunoglobulin heavy chain-encoding gene?
Which one or more of the following statements correctly describe(s) the addition of N-nucleotides during the rearrangement of the immunoglobulin heavy chain-encoding gene?
(A) Addition of N-nucleotides is template encoded.
(B) N-nucleotides are added by terminal deoxynucleotidyl transferase.
(C) The added N-nucleotides are common in V-D and D-J junction.
(D) N-nucleotides are added by the DNA polymerase II.
Answer
Answer: (B) N-nucleotides are added by terminal deoxynucleotidyl transferase.
(C) The added N-nucleotides are common in V-D and D-J junction.
Explanation:
Terminal deoxynucleotidyl transferase (TdT) adds N-nucleotides in a template-independent manner at the V-D and D-J junctions during the rearrangement of the immunoglobulin heavy chain gene, enhancing antibody diversity.
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