Analysis of Complete Mitochondrial Genome of Bohadschia argus (Jaeger, 1833) (Aspidochirotida, Holothuriidae)

SIMPLE SUMMARY: Mitochondrial genomes are a type of specific genetic marker, characterized in most animals by a rapid mutation rate, high copy numbers and the absence of genetic recombination. They are widely applied in phylogenetics, population genetics and ecological research. Bohadschia argus is a sea cucumber with high economic value. Currently, the mitochondrial genomic data of B. argus are not available. In this study, next-generation sequencing was performed on the mitochondrial genome of B. argus. The gene arrangement order in the mitochondrial genome of B. argus was consistent with the echinoderm ground pattern. Finally, phylogenetic analysis using the 13 protein-coding genes of mitochondria confirmed the phylogenetic position of B. argus. ABSTRACT: Bohadschia argu is a kind of sea cucumber with high economic value; it is the only undisputed species in the genus Bohadschia. In this study, the complete mitochondrial genome (mitogenome) of B. argus was acquired through high-throughput sequencing. The mitochondrial genome of B. argus was 15,656 bp in total length and contained a putative control region (CR) and 37 typical genes of animal mitochondrial genomes, including 13 protein-coding genes (PCGs), 2 ribosomal RNA genes (rrnS and rrnL) and 22 transfer RNA genes (tRNA). The sizes of the PCGs ranged from 168 bp to 1833 bp, and all PCGs except nad6 were encoded on the heavy chain (H). Both rrnS and rrnL were also encoded on the H chain. Twenty-two tRNA genes had positive AT skew and GC skew. All tRNAs had a typical cloverleaf secondary structure except for trnI, in which an arm of dihydrouridine was missing. B. argus shared the same gene arrangement order (the echinoderm ground pattern) as other species in Aspidochirotida. Phylogenetic analysis clearly revealed that B. argus belongs as a member of the Holothuriidae, and it is closely related to members of Actinopyga and Holothuria.