Additional description and genome analyses of Caenorhabditis auriculariae representing the basal lineage of genus Caenorhabditis

• DOI: 10.1038/s41598-021-85967-z
• Publication Date: 2021-03-24T11:04:07Z
• Authors: Mehmet Dayi; Natsumi Kanzaki; Simo Sun; Tatsuya Ide; Ryusei Tanaka; Hayato Masuya; Kimiko Okabe; Hisashi Kajimura; Taisei Kikuchi
• Keywords: 0301 basic medicine; Genome, Helminth; Science; Q; R; Genomics; Article; Evolution, Molecular; 03 medical and health sciences; Caenorhabditis; Medicine; Animals; Genes, Helminth; Phylogeny

AbstractCaenorhabditis auriculariae,which was morphologically described in 1999, was re-isolated from aPlatydemamushroom-associated beetle. Based on the re-isolated materials, some morphological characteristics were re-examined and ascribed to the species. In addition, to clarify phylogenetic relationships with otherCaenorhabditisspecies and biological features of the nematode, the whole genome was sequenced and assembled into 109.5 Mb with 16,279 predicted protein-coding genes. Molecular phylogenetic analyses based on ribosomal RNA and 269 single-copy genes revealed the species is closely related toC. sonoraeandC. monodelphisplacing them at the most basal clade of the genus.C. auriculariaehas morphological characteristics clearly differed from those two species and harbours a number of species-specific gene families, indicating its usefulness as a new outgroup species forCaenorhabditisevolutionary studies. A comparison of carbohydrate-active enzyme (CAZy) repertoires in genomes, which we found useful to speculate about the lifestyle ofCaenorhabditisnematodes, suggested thatC. auriculariaelikely has a life-cycle with tight-association with insects.