Characterization of the complete sequence analysis of mitochondrial DNA of Japanese rare bumblebee species Bombus cryptarum florilegus

Abstract

The bumblebee (genus Bombus) distributed in the Northern Hemisphere is mostly decreasing and is extinct in some populations on several species within the last half century. The bumblebee Bombus cryptarum florilegus is designated as a near threatened species in Japan because of the number of individuals declining due to complex environmental problems. This species is also confused classification and phylogenetic position from valid species to one subspecies of Eurasian common bumblebees. We firstly analyzed the complete mitochondrial genome of the B. cryptarum florilegus from Hokkaido, Japan using Next generation sequencing technology. The mitochondrial genome is a circular molecule of approximately 1.6 kb, and includes 13 protein-coding genes (PCGs), 23 tRNA genes, 2 rRNA genes, and 1 AT-rich control region, besides two tRNA-Met. Start codons ATT, ATG and ATA were found in three, four and six genes, respectively, while stop codons TAA, TAG and incomplete stop codon TA were observed in 11, one and one gene, respectively. The heavy strand (H-strand) was predicted to have nine PCGs and 14 tRNA genes, while the light strand (L-strand) was predicted to contain four protein-coding, nine tRNA, and two rRNA genes. The phylogenetic relationship based on the maximum likelihood method using 13 PCGs was consistent with some previous studies in which a closely relationship between B. cryptarum florilegus and B. lucorum. The complete sequence of the mitochondrial DNA in bumblebees is an effective information for conservation genetics.