Alignment maps and homology analysis of the J-C intron in human, mouse, and rabbit immunoglobulin kappa gene

The statistically significant shared oligonucleotides (block identities) ofthe intervening region (J5-C) in the human, mouse, and rabbitimmunoglobulin (Ig)-kappa gene were determined. These identities maintaintheir order (do not cross) and never connect with any Ig-kappa segmentexternal to the intron region. The two regions of pronounced similarity are(1) the vicinity of the established enhancer element (Queen and Baltimore1983) and (2) a 200-bp region approximately 1 kb upstream that we havelabeled the second enhancer element. Similarity is strong between the humanand mouse sequences in the neighborhood of the first enhancer element andmore pronounced between the human and rabbit sequences in the vicinity ofthe second enhancer region. The overall extent of similarity between themouse and rabbit sequences is less than that between the human and mousesequences and that between the human and rabbit sequences. All close andlarge dyad-symmetry pairings were ascertained and their possible relationsto the enhancer elements discussed.