Phylogenetic Relationships among Honey Bee Subspecies Apis mellifera caucasia and Apis melliferacarpathica Based on the Sequences of the Mitochondrial Genome.

The sequences of the complete mitochondrial genome of the honey bee Apis mellifera L. subspecies Apis mellifera caucasia Pollmann, 1889 (AP018404, 16 341 bp) and Apis melliferacarpathica Foti et al., 1965 (AP018403, 16 336 bp) are sequenced for the first time. Mitochondrial DNA (mtDNA) of both subspecies contains 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and one AT-rich regulatory region. The ratio of transitions to transversions (tr/tv) in complete mtDNA between A. m. caucasia and A. m. carpathica was 2.05, which reflects the formation of adaptations to changing environmental conditions. Genes with the highest GC content—COX1 (24%), COX2 (19.6%), CYTB (19.1%), COX3 (17.2%), and ND1 (17.2%)—can be highly polymorphic and can be used in phylogenetic and population studies of bees. The majority of mtDNA genes of both subspecies are located on the heavy strand (9 protein-coding genes and 14 tRNA genes), while other genes (4 protein-coding genes, 2 rRNA genes, and 8 tRNA genes) are located on the light strand. Cluster analysis of the complete mtDNA sequence and assessment of the structure of the tRNA-Leu(UUR)–COX2 intergenic region with a single Q element 192 bp in length showed that both subspecies A. m. caucasia and A. m. carpathica are representatives of the line C with haplotypes C2 and C2j, respectively. Honey bee subspecies A. m. caucasia and A. m. carpathica can be differentiated from each other by 34 unique SNPs in 11 mtDNA genes and the XbaI restriction marker in the ND5 gene. These genetic markers can contribute to the preservation of purebred gene pools of honey bee subspecies A. m. caucasia and A. m. carpathica within their natural range. [ABSTRACT FROM AUTHOR]