Germ-line
theory: Suggests that genetic information for each antibody
is encoded, in its entirety, within the germ-line genome.
After revaluations and calculations the germ-line
theory was not accurate because there simply was not enough DNA to fit the
size of antibody repertoire.
Recombination
Signal Sequences (RSS): Specific DNA sequence motifs that
ensure one of each type of segment (V & J for the light chain OR V, D &
J for the heavy chain) is included in the recombined variable region gene.
The RSS for the V region must be 3’, while the
RSS for the J region must be 5’ in order to be compatible for joining.
Terminal
deoxynucleotidyl Transferase (TdT): Enzyme responsible
for the generation of additional diversity in the CDR3 region of the antibody
heavy chain
TdT, RAG1 and RAG2 are the
three proteins implicated in V(D)J recombination that are unique to
lymphocytes.
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