Structure and evolution of the mitochondrial control region of leaf beetles (Coleoptera: Chrysomelidae): a hierarchical analysis of nucleotide sequence variation.

  • publication
  • 06-02-2003

Mardulyn P, Termonia A, Milinkovitch MC. J. Mol. Evol. 2003 Jan;56(1):38-45. 10.1007/s00239-002-2378-1.

To assess the levels of variation at different evolutionary scales in the mitochondrial (mt) control region of leaf beetles, we sequenced and compared the full mt control region in two genera ( Chrysomela and Gonioctena), in two species within a genus ( Gonioctena olivacea and G. pallida), in individuals from distant populations of these species in Europe, and in individuals from populations separated by moderate (10- to 100-km) to short (<5-km) distances. In all individuals, a highly repetitive section consisting of the tandem repetition of 12 to 17 imperfect copies of a 107- to 159-bp-long core sequence was observed. This repetitive fragment accounts for roughly 50% of the full control-region length. The sequence variability among repeated elements within the control region of a given individual depends on the species considered: the variability within any G. olivacea individual is much higher than that within G. pallida individuals. Comparisons of the repeated elements, in a phylogenetic framework, within and among individuals of G. olivacea and G. pallida suggests that the repetitive section of the control region experienced recurrent duplications/deletions, leading to some degree of concerted evolution. Comparisons between Chrysomela and Gonioctena control regions revealed virtually no significant sequence similarity, except for two long stretches of A's and several [T(T)A(A)] repeats, all found in the control region of other insect orders. Our analyses allowed us to identify portions of the control region with enough variation for population genetic or phylogeographic studies.

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