Characterization and phylogenetic analysis of the first complete mitochondrial genome of Cylicocyclus radiatus.
Abstract: Cylicocyclus spp. are common parasites in the intestine of equine animals. Hosts infected by these strongylid nematodes might face emaciation, anemia, and even death, all of which lead to significant economic losses. In the present study, the complete mitochondrial genome (mitogenome) of Cylicocyclus radiatus, the type species of the genus Cylicocyclus, was sequenced and characterized for the first time using next-generation sequencing technology. Results show that the mitogenome of C. radiatus is a double-stranded 13,836 bp circular molecule, containing 12 protein-coding genes, 22 tRNA genes, two rRNA genes, and two non-coding regions. Moreover, it has a clear bias in nucleotide composition and codon preference towards protein-coding genes with elevated AT content. All protein-coding genes are initiated by ATT and TTG codons, and almost all of them end with complete TAA and TAG termination codons; only the COШ gene harbors the incomplete T termination codon. All tRNA genes fold into an atypical clover-leaf secondary structure. The tRNA-Ser genes possess a TΨC arm and variable loop, but lack the dihydrouridine arm and loop. Twenty tRNAs contain the dihydrouridine arm and loop, in which the variable TΨC arm and loop are replaced by a "TV-replacement loop". Most tRNA gene secondary structures contain G-U, U-U, and A-G mismatches. Phylogenetic analysis based on nucleotide sequences of the 12 protein-coding genes using maximum likelihood and Bayesian inference indicated that C. radiatus is related more closely to Cylicocyclus nassatus than to Cylicocyclus insigne. In summary, this study provides the first annotated sequence of the mitogenome of C. radiatus, paving the way for further research on species classification and the molecular evolution of strongylid nematodes.
Copyright © 2020 Elsevier B.V. All rights reserved.
Publication Date: 2020-04-03 PubMed ID: 32438201DOI: 10.1016/j.vetpar.2020.109097Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
This research article is about the sequencing and characterization of the complete mitochondrial genome of Cylicocyclus radiatus, a common intestinal parasite in equines, for the first time. The findings discuss the mitogenome’s characteristics and how they relate to other species, potentially aiding further investigation into species classification and the molecular evolution of such nematodes.
Understanding Cylicocyclus Radiatus
- The study revolves around Cylicocyclus radiatus, a prominent parasite seen in equines’ intestines.
- These strongylid nematodes pose a threat to the host by inducing conditions like emaciation, anemia, and can possibly lead to host death. As a result, these parasites cause significant economic losses.
Characterization of the Mitogenomic Structure
- The complete mitochondrial genome (mitogenome) of C. radiatus was characterized through next-generation sequencing technology, marking the first time this has been done.
- The mitogenome of C. radiatus is a 13,836 base pair (bp) double-stranded circular molecule.
- It comprises 12 protein-coding genes, 22 transfer RNA (tRNA) genes, two ribosomal RNA (rRNA) genes, and two non-coding regions.
- There is a noticeable bias in nucleotide composition and codon preference towards protein-coding genes with an elevated Adenine-Thymine (AT) content.
Codon and tRNA Gene Analysis
- All protein-coding genes initiate by Adenine-Thymine-Thymine (ATT) and Thymine-Thymine-Guanine (TTG) codons.
- Most genes end with TAA and TAG termination codons. The only exception is the COШ gene that has an incomplete Thymine (T) termination codon.
- All transfer RNA (tRNA) genes fold into an uncommon clover-leaf secondary structure.
- The tRNA-Ser genes have a TΨC arm and variable loop but do not have a dihydrouridine arm and loop.
- Most tRNA genes contain mismatches such as Guanine-Uracil (G-U), Uracil-Uracil (U-U), and Adenine-Guanine (A-G).
Phylogenetic Analysis Results
- A phylogenetic study using a maximum likelihood and Bayesian inference based on the nucleotide sequences of the 12 protein-coding genes showed a closer relation of C. radiatus to Cylicocyclus nassatus than to Cylicocyclus insigne.
- The detailed findings from this research can boost future studies on species classification and the molecular evolution of strongylid nematodes.
Cite This Article
APA
Hu L, Zhang M, Sun Y, Bu Y.
(2020).
Characterization and phylogenetic analysis of the first complete mitochondrial genome of Cylicocyclus radiatus.
Vet Parasitol, 281, 109097.
https://doi.org/10.1016/j.vetpar.2020.109097 Publication
Researcher Affiliations
- College of Life Science, Henan Normal University, Xinxiang, 453007, China.
- College of Life Science, Henan Normal University, Xinxiang, 453007, China.
- College of Life Science, Henan Normal University, Xinxiang, 453007, China.
- College of Life Science, Henan Normal University, Xinxiang, 453007, China. Electronic address: buyanzhen@htu.cn.
MeSH Terms
- Animals
- Evolution, Molecular
- Genome, Mitochondrial / genetics
- Phylogeny
- Sequence Analysis, DNA
- Strongyloidea / classification
- Strongyloidea / genetics
Conflict of Interest Statement
Declaration of Competing Interest The authors declare that there are no competing interests.
Citations
This article has been cited 10 times.- Gao JF, Zhang AH, Wei W, Jia B, Zhang J, Li B, Chen YY, Sun YY, Hou MR, Liu XW, Wang JW, Zhang XH, Wang CR. The complete mitochondrial genome of Ogmocotyle ailuri: gene content, composition and rearrangement and phylogenetic implications. Parasitology 2023 Jul;150(8):661-671.
- Gao Y, Zhang Z, Wang C, Zhao K. The Mitochondrial Genome of Cylicocyclus elongatus (Strongylida: Strongylidae) and Its Comparative Analysis with Other Cylicocyclus Species. Animals (Basel) 2022 Jun 17;12(12).
- Li X, Wang L, Chen Y, Wang X, Zhou X, Xie Y. Complete mitochondrial genome of cylicocyclus auriculatus: molecular structure and phylogenetic analysis. Mitochondrial DNA B Resour 2022;7(2):419-421.
- Gao JF, Mao RF, Li Y, Sun YY, Gao ZY, Zhang XG, Jin ZH, An Q, Zhang ZH, Zhang AH, Wei W, Lan Z, Wang CR. Characterization of the mitochondrial genome of Tetrameres grusi and insights into the phylogeny of Spirurina. Int J Parasitol Parasites Wildl 2022 Apr;17:35-42.
- Wu J, Han M, Gao L, Kang S, Niu X, Liu B, Wang T. The first complete mitochondrial genome and phylogenetic analysis of Clypeaster virescens (Clypeasteroida, Clypeasteridae). Sci Rep 2026 Jan 4;16(1):3363.
- Abbas G, Nielsen MK, E-Hage C, Ghafar A, Beveridge I, Bauquier J, Beasley A, Wilkes EJA, Carrigan P, Cudmore L, Jacobson C, Hughes KJ, Jabbar A. Recent advances in intestinal helminth parasites of horses in the Asia-Pacific region: Current trends, challenges and future directions. Int J Parasitol Drugs Drug Resist 2025 Dec;29:100622.
- Zhang H, He Q, Zhao Z, Zhang B, Zhou J, Wang C, Yi C, Zhao M. Mitochondrial Genome Comparison and Phylogenetic Analysis of Four Species of Dung Beetles (Coleoptera: Scarabaeidae: Scarabaeinae). Ecol Evol 2025 Aug;15(8):e71906.
- Jia H, Tang L, Fu Y, Xiong Y, Yan L, Shao C, Li K, Zhang D, Hu D. The first mitogenome of Petrovinema skrjabini from Equus ferus przewalskii: a phylogenetic analysis within the Strongylidae family. Parasit Vectors 2025 Jul 11;18(1):278.
- Hao Y, Li B, Ma L, Xu M, Niu P, Bu Y. The complete mitochondrial genome of Cylicocyclus ultrajectinus (Ihle, 1920). Mitochondrial DNA B Resour 2024;9(11):1518-1521.
- Ma L, Li J, He J, Jiang T, Hao Y, Bu Y. Characterization and phylogenetic analysis of the mitochondrial genome of Cylicostephanus longibursatus. Parasitol Res 2024 Oct 29;123(10):363.
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
