Figure 4

Possible evolutionary mechanism of recombination in Alydidae and Malcidae. A, recombination in Alydidae. Panel A.a, the ancestral state. Dup.A1 and Dup.B1 were two original copies of the repetitions. Panel A.b, Dup.A2 and Dup.B2 between tRNA-I and tRNA-Q were repetitions of the Dup.A1 and the Dup.B1 formed by the tandem duplication and random loss. Panel A.c, Dup.A2 changed its direction by intramitochondrial recombination [35], forming the extant state. B, the recombination in Malcidae. Panel B.a, Dup.C1 was the original copy of thr repetition in the intergenic spacer between tRNA-H and ND4. Panel B.b, formation of the mini circle of Dup.C1 by intramitochondrial recombination [35]. Panel B.c, the mini circle of the Dup.C1 integrated into the control region of another mt-genome. Panel B.d, Dup.C2, the repetition of the Dup.C1, formed in the control region.