Figure 2.

Schematic Diagram of the V(D)J Somatic Recombination to Generate T Cell Receptor (TCR).

The TCR is composed of the alpha (α) and beta (β) subunit. During T cell development, the loci that encode T cell receptor α and β-chains are rearranged. Variable (V), diversity (D), joining (J), and constant (C) gene segments are represented as blue, red, green, and purple rectangles, respectively. Diversity for the β chain is first created via recombination of D and J segments, followed by the V segments, and finally one of two C segments. Diversity for the α chain is created via recombination of V and J segments, followed by the one C segment. This process also involves the deletion and insertion of nucleotides at the V–D, D–J junctions for the β chain and V–J junctions for the α chain, thus adding more potential diversity to the TCR repertoire.