Fig. 6.
Comparative configuration of IgL loci. (A) Igκ rearrangements are restricted to a single IgL cluster. (B/C) The single transcriptional orientation of λ segments of man/mouse necessitates VJ-rearrangement by deletion within and between clusters. (D) Zebrafish have extensive (V–J–C) clusters, those of Chr19 are shown. A potential rearrangement for VJ–C clones (EF222427, EF222428) is depicted. Inversional inter-cluster rearrangements preserve intervening DNA, thus maximizing VL and JL available for subsequent rearrangements. Numbers of segments and physical distances (given in kb) for mouse/human loci are from IMGT [42]. All zebrafish VL and JL identified have 1 and 2 turn RSS similar to Igκ loci of humans/mouse, respectively.