Regulation of IgL Chain Recombination

The immunoglobulin light chain loci (Igκ and Igλ) are recombined via V(D)J recombination at the pre-B cell stage during B cell differentiation. The recombination process is highly regulated on multiple levels to ensure proper timing and locus specificity. In this article, we focus on a number of mechanisms which contribute to the tight control of the rearrangement, focusing on the IgL locus, which is the primary IgL chain utilized in both mice and humans. We explain how regulation of locus accessibility, cellular signaling pathways, and transcription factor binding influence the recombination process. We also note regulation of the 'allelic exclusion' phenomenon, where only one B cell receptor is expressed in a single lymphocyte.