The complete mitochondrial genome sequence of Scolopendra mutilans L. Koch, 1878 (Scolopendromorpha, Scolopendridae), with a comparative analysis of other centipede genomes

Abstract

Scolopendra mutilans L. Koch, 1878 is an important Chinese animal with thousands of years of medicinal history. However, the genomic information of this species is limited, which hinders its further application. Here, the complete mitochondrial genome (mitogenome) of S. mutilans was sequenced and assembled by next-generation sequencing. The genome is 15,011 bp in length, consisting of 13 protein-coding genes (PCGs), 14 tRNA genes, and two rRNA genes. Most PCGs start with the ATN initiation codon, and all PCGs have the conventional stop codons TAA and TAG. The S. mutilans mitogenome revealed nine simple sequence repeats (SSRs), and an obviously lower GC content compared with other seven centipede mitogenomes previously sequenced. After analysis of homologous regions between the eight centipede mitogenomes, the S. mutilans mitogenome further showed clear genomic rearrangements. The phylogenetic analysis of eight centipedes using 13 conserved PCG genes was finally performed. The phylogenetic reconstructions showed Scutigeromorpha as a separate group, and Scolopendromorpha in a sister-group relationship with Lithobiomorpha and Geophilomorpha. Collectively, the S. mutilans mitogenome provided new genomic resources, which will improve its medicinal research and applications in the future.

Keywords: Chilopoda; Chinese medicinal materials; Scolopendra mutilans; mitogenome.

Figure 1.

Mitochondrial genome map of the Scolopendra mutilans. Genes drawn inside the circle are transcribed clockwise, and those outside are counterclockwise. PCGs are shown as brown arrows, rRNA genes as green arrows, tRNA genes as pink arrows. The innermost circle shows the GC content. GC content is plotted as the deviation from the average value of the entire sequence.

Figure 2.

Variation in length and base composition of each of the 13 core protein coding genes (PCGs) among eight centipedes’ mitochondrial genomes A PCG length variation B GC content across PCGsC AT skew D GC skew.

Figure 3.

Mitogenome synteny among eight centipede species. Synteny analyses were generated in Mauve 2.4.0. A total of six large homologous regions were identified among the eight mitogenomes, while the sizes and relative positions of the homologous fragments varied across the mitogenomes.

Figure 4.

A Molecular phylogeny of eight centipede species based on Maximum Likelihood inference analysis of 13 protein-coding genes (PCGs) B Traditional morphological classification based on the position of spiracles and the variation of larvae.