Sequences at the somatic recombination sites of immunoglobulin light-chain genes

Abstract
The entire nucleotide sequence of a 1.7-kilobase [mouse] embryonic DNA fragment containing 5 joining (J) DNA segments for mouse immunoglobulin .KAPPA. chain gene was determined. Each J DNA segment can encode amino acid residues 96-108. Comparison of 1 of the 5 J DNA sequences with those of an embryonic variable (V) gene and a complete .KAPPA. chain gene permitted localization of a precise recombination site. The 5''-flanking regions of J DNA segments could form an inverted stem structure with the 3''-non-coding region of embryonic V genes. This hypothetical structure and gel-blotting analysis of total embryo and myeloma DNA suggest that the somatic recombination may be accompanied by excision of an entire DNA segment between a V gene and a J DNA segment. Antibody diversity may in part be generated by modulation of the precise recombination sites.