Mouse RSS spacer sequences affect the rate of V(D)J recombination

The diversity of antigen-specific receptors [immunoglobulins (Ig) and T-cell receptors (Tcr)] is generated largely during the assembly of the genetic elements - named V, D, and J - that encode the variable region of both Ig and Tcr. This assembly involves a somatic, cell-type specific, site-specific rearrangement process termed V(D)J recombination. The specific sites involved in V(D)J recombination are termed recombination signal sequences (RSS). An RSS associated with an Igk-V element, for instance, and an RSS associated with an Igk-J element, together with the entire stretch of DNA separating them, are excised from the chromosome as a circular molecule, with the result that a (potentially) functional gene encoding a kappa light chain, Igk, is formed.