A new marker for molecular phylogenetic studies in Odonata including parts of conservative histone H3 and H4 genes and spacer between them
A new molecular marker, the histone H3-H4 region, containing partial coding sequences of the genes of histones H3 and H4 and the non-coding spacer between them, is proposed. This marker is potentially useful for molecular phylogenetic studies at generic, species, and even intra-species level in insects. The highly conservative histone coding sequences ensure universality of primers and the ease of primary alignment, while the highly variable non-coding spacer provides enough variation for analyses at short evolutionary distances. In insects, the histone genes reside in the histone repeat which is tandemly repeated in dozens to hundred copies forming the so-called histone cluster. However, the order and orientation of the histone genes in the histone repeat is variable among orders, which exerts some limitation for the use of the proposed marker. The marker efficacy is hereby shown for Odonata (dragonflies and damselflies), where it well resolved families, genera and species involved and provided an insight into the relationship of two Sympetrum species, Sympetrum croceolum and S. uniforme. The same combination of original primers should work also in Diptera.