title: The complete mitochondrial genome of Strongylus equinus (Chromadorea: Strongylidae): Comparison with other closely related species and phylogenetic analyses.
abstract: The roundworms of genus Strongylus are the common parasitic nematodes in the large intestine of equine, causing significant economic losses to the livestock industries. In spite of its importance, the genetic data and epidemiology of this parasite are not entirely understood. In the present study, the complete S. equinus mitochondrial (mt) genome was determined. The length of S. equinus mt genome DNA sequence is 14,545 bp, containing 36 genes, of which 12 code for protein, 22 for transfer RNA, and two for ribosomal RNA, but lacks atp8 gene. All 36 genes are encoded in the same direction which is consistent with all other Chromadorea nematode mtDNAs published to date. Phylogenetic analysis based on concatenated amino acid sequence data of all 12 protein-coding genes showed that there were two large branches in the Strongyloidea nematodes, and S. equinus is genetically closer to S. vulgaris than to Cylicocyclus insignis in Strongylidae. This new mt genome provides a source of genetic markers for the molecular phylogeny and population genetics of equine strongyles.
authors.affiliation: College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang Province 163319, PR China.
authors.forename: Wen-Wen
authors.initials: WW
authors.lastname: Xu
authors.affiliation: College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang Province 163319, PR China.
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Qiu
authors.affiliation: State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, PR China.
authors.forename: Guo-Hua
authors.initials: GH
authors.lastname: Liu
authors.affiliation: College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang Province 163319, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang Province 163319, PR China.
authors.forename: Ze-Xuan
authors.initials: ZX
authors.lastname: Liu
authors.affiliation: College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang Province 163319, PR China.
authors.forename: Hong
authors.initials: H
authors.lastname: Duan
authors.affiliation: College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang Province 163319, PR China.
authors.forename: Dong-Mei
authors.initials: DM
authors.lastname: Yue
authors.affiliation: College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang Province 163319, PR China.
authors.forename: Qiao-Cheng
authors.initials: QC
authors.lastname: Chang
authors.affiliation: College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang Province 163319, PR China. Electronic address: chunrenwang@sohu.com.
authors.forename: Chun-Ren
authors.initials: CR
authors.lastname: Wang
authors.affiliation: Animal and Plant Department, Quanzhou Entry-Exit Inspection and Quarantine Bureau, Quanzhou, Fujian Province, 362000, PR China. Electronic address: zxcpxy@163.com.
authors.forename: Xing-Cun
authors.initials: XC
authors.lastname: Zhao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D018509:DNA, Helminth / Q000737:chemistry*; D004272:DNA, Mitochondrial / Q000737:chemistry*; D003576:Electron Transport Complex IV / Q000235:genetics; D018397:Equidae / Q000469:parasitology; D054629:Genome, Mitochondrial / Q000235:genetics*; D006736:Horses; D007420:Intestine, Large / Q000469:parasitology; D010802:Phylogeny; D012343:RNA, Transfer / Q000235:genetics; D013319:Strongyle Infections, Equine / Q000469:parasitology; D013323:Strongylus / Q000145:classification / Q000235:genetics*
chemical_list: D018509:DNA, Helminth; D004272:DNA, Mitochondrial; D012343:RNA, Transfer; D003576:Electron Transport Complex IV
keywords: Comparative analyses; Mitochondrial genome; Phylogenetic analyses; Strongylus equinus