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Junctional diversity of antibody molecules results from
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- the addition of switch region nucleotides
- the addition of N and P nucleotides
- the joining of V, D and J segments
- mutations in complementarity-determining regions
Correct Option: B
Generation of junctional diversity starts as the proteins, recombination activating gene-1 and -2 (RAG1 and RAG2), along with DNA repair proteins, such as Artemis, are responsible for single-stranded cleavage of the hairpin loops and addition of a series
of palindromic, ‘P’ nucleotides. Subsequent to this, the enzyme, terminal deoxynucleotidyl transferase (TdT), adds further random ‘N’ nucleotides. The newly synthesised strands anneal to one another, but mismatches are common.
