Diagrams of (A) three types of ∼20S editosomes and (B) KREPB6, KREPB7, and KREPB8 proteins that are each uniquely associated with one type of editosome. The KREPB6, KREPB7, and KREPB8 proteins (B6, B7, and B8) are aligned by their U1 zinc finger motif and show their relative sizes. The three editosomes have either KREN3 (N3) or KREN2 (N2) insertion site or KREN1 (N1) deletion site endonucleases. The KREX1 exoUase (X1) is uniquely associated with B8/N1 editosomes. All three editosomes have a common set of 12 proteins that are organized into the KREPA1, KRET2, and KREL2 insertion subcomplex (A1, T2, L2); the KREPA2, KREX2, and KREL1 deletion subcomplex (A2, X2, L1); the KREPA3, KREPA4, KREPA5, and KREPA6 interacting proteins (A3, A4, A5, A6); and KREPB4 and KREPB5 that have degenerate RNase III motifs (B4, B5).
