Mitochondrial genome of Caenorhabditis nigoni (Rhabditida: Rhabditidae)

To facilitate comparative genomic study in the Caenorhabditis species, the mitochondrial genome (mitogenome) of a nematode species Caenorhabditis nigoni (previous name: Caenorhabditis sp. 9) was generated using next-generation sequencing. The mitogenome length is 13,413 bp, containing 12 protein-coding genes (PCGs), 2 ribosomal RNA genes (rRNAs), 22 transfer RNA genes (tRNAs) and 2 non-coding regions (NCR). The genome organization and nucleotide composition is very similar to that of the mitogenome of C. elegans and C. briggsae. Mitogenome of C. nigoni shows higher sequence similarity to C. briggsae than to C. elegans, which is consistent with the fact that C. nigoni is a sister species of C. briggsae. However, as in C. elegans, two NCRs present in the mitogenome of C. briggsae are missing in C. nigoni. The mitogenome sequence of C. nigoni plays an important role in further studies of phylogenetics, population genetics and evolutionary genetics in nematode species.