title: Amino acids at the site of V kappa-J kappa recombination not encoded by germline sequences.
abstract: Murine V kappa-J kappa recombination is characterized by a maintenance of size at the site of recombination and the use of nucleic acids found only in germline sequences. This is in contrast to heavy chain VH-D-JH assembly where random nucleotides are added at the recombination sites to produce considerable size variation, even though the heptamer/nonomer recombination sequences are identical in both kappa and heavy chain genes. We have examined the origin of an unusual amino acid, Ile, found at the site of V kappa-J kappa recombination in antigalactan antibodies, by sequence analysis of the corresponding rearranged and germline genes. Results indicate that the Ile codon can be generated by use of a single nucleotide 3' of the V kappa segment in combination with the second and third nucleotides of the first codon of J kappa 5 or J kappa 4. However, several antigalactan antibodies express Ile in combination with J kappa 2. An Ile codon cannot be generated by recombination in any reading frame between germline V kappa and J kappa 2 segments. These results suggest that the origin of the Ile codon in lines using J kappa 2 may represent a novel even in murine light chain assembly, possibly similar to the de novo addition of nucleotides observed in heavy chain gene recombination.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D004247:DNA / Q000235:genetics; D004262:DNA Restriction Enzymes; D005685:Galactans / Q000276:immunology; D006825:Hybridomas / Q000276:immunology; D007144:Immunoglobulin J-Chains / Q000235:genetics*; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D007145:Immunoglobulin kappa-Chains / Q000235:genetics*; D007532:Isoleucine; D008099:Liver / Q000032:analysis; D051379:Mice; D008807:Mice, Inbred BALB C; D009693:Nucleic Acid Hybridization; D011995:Recombination, Genetic
chemical_list: D005685:Galactans; D007144:Immunoglobulin J-Chains; D007135:Immunoglobulin Variable Region; D007145:Immunoglobulin kappa-Chains; D007532:Isoleucine; D004247:DNA; D004262:DNA Restriction Enzymes