Abstract
In this study, we sequenced the complete mitochondrial genome of Argali sheep (Ovis ammon). The total length was 16,612 bp, which contained 13 protein-coding genes (PCGs), 22 tRNA genes, 2 rRNA genes, and a control region (D-loop). Eight tRNA genes with one PCG (ND6) encoded on the L-strand, others were encoded on the H-strand. The neighbor-joining analysis shows that Argali sheep has a close relationship with the same genus species of Ovis aries and Ovis orientalis. This study has provided new data for the phylogeny of Argali sheep.
Keywords: Mitochondrial genome, Argali sheep, phylogenetic analysis
Ovis ammon (Ovis, Caprinae) also known as Argali sheep, is one of the members of Caprinae (Kumar et al. 2016; Smith and Xie 2010). In China, this gregarious animal is extensively distributed in the western mountain, including Junggar mountains, Tian Shan mountains, Pamirs, Altun mountains, Kunlun mountains, Qilian mountains, Qinghai-Tibet plateau, and Inner Mongolia plateau (Yu et al. 2008). The wild populations of Argali sheep are declining, so it was classified as near threatened species by International Union for Conservation of Nature (The IUCN Red List of Threatened Species 2008). Hence, our study reported its entire mitochondrial genome data, which had supplemented the mitochondrial genome data of the subfamily Caprinae.
The samples were collected from Xinjiang Uygur Autonomous Region (75°E ∼ 95°E; 35°N ∼ 50°N) and stored in Zoology laboratory of Sichuan Agricultural University (Accession:000745). The total genomic DNA was extracted from muscles using phenol-chloroform extraction method (Sambrook et al. 1990). The mitochondrial genome of Argali sheep was amplified and sequenced by 22 pairs of primers designed based on the conservative regions of O. ammon (HM236188). The sequenced data were edited and assembled by DNAstar (Swayne et al. 2015) and the phylogenetic tree was constructed using MEGA7.0 (Kumar et al. 2016).
The complete mitochondrial genome of Argali sheep is 16,612 bp (Genebank: MN564883), including 13 protein-coding genes (PCGs), 22 tRNA genes, 2 rRNA genes, and a control region (D-loop), which is similar to other species of Caprinae (Meadows et al. 2011). The base composition of mtDNA is A (33.67%), G (13.08%), T (27.29%), C (25.96%), so the percentage of A + T (60.96%) is higher than G + C (39.04%), A-T bias is more significant. Among the 13 PCGs, the longest one is 1821 bp (ND5) and the shortest is 201 bp (ATP8). Three PCGs (ND2, ND3, ND5) used ATA as start codon and the remainders were ATG. Six PCGs terminated with TAA, while Cytb terminated with AGA. The incomplete stop codon(T−) was observed in ND1, ND2, ATP6, COX3, ND3, and ND4. There were eight tRNA genes (tRNAGln, tRNAAla, tRNAAsn, tRNACys, tRNATyr, tRNASer, tRNAGlu, and tRNAPro) with one PCG (ND6) encoded on the L-strand, and the other PCGs were encoded on the H-strand. The 12s rRNA and 16s rRNA were located between tRNAphe and tRNAleu, which was separated by tRNAval. In the sequence, we find one control region(CR), that is located between tRNAPro and tRNAPhe.
The phylogenetic tree was constructed with the other 12 species from Caprinae, using Bos taurus as an outgroup (Figure 1). The phylogenetic analysis shows that Argali sheep has a close relationship with Ovis aries and Ovis orientalis, which belong to genus Ovis, and the topology structure was consistent with the previous study (Sun et al. 2017). This study provides new data for the phylogeny of Argali sheep.
Figure 1.
Neibour-joining(NJ) phylogenetic tree constructed based on 13 protein coding genes of Ovis ammon and other 12 Caprinae species, using Bos taurus as an outgroup and numbers at the branches indicated the bootstrapping values with 1000 replications. Solid triangle represents a sequence in this study.
Funding Statement
This work was supported by the National Natural Science Foundation of China under Grant [31870355].
Disclosure statement
The authors declare no conflict of interest and are alone responsible for the content and writing of the paper.
References
- Kumar S, Stecher G, Tamura K. 2016. MEGA7: Molecular Evolutionary Genetics Analysis version 7.0 for bigger datasets. Mol Biol Evol. 33(7):1870. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Meadows JRS, Hiendleder S, Kijas JW. 2011. Haplogroup relationships between domestic and wild sheep resolved using a mitogenome panel. Heredity (Edinb). 106(4):700–706. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sambrook J, Fritsch EF, Maniatis T. 1990. Molecular cloning: a laboratory manual. Anal Biochemist. 186:182–183. [Google Scholar]
- Smith AT, Xie Y. 2010. A field guide to the mammals of China. Changsha (China): Hunan Education Press. [Google Scholar]
- Sun MH, Yue CW, Liu TT, Li L, Liu HY. 2017. The complete mitochondrial genome of Budorcas taxicolor bedfordi (Artiodactyla: Bovidae) and phylogenetic studies of Caprinae. Conservation Genet Resour. 9(3):397–400. [Google Scholar]
- Swayne DE, Suarez DL, Spackman E, Jadhao S, Dauphin G, Kim Torchetti M, Mc Grane J, Weaver J, Daniels P, Wong F, et al. 2015. Antibody titer has positive predictive value for vaccine protection against challenge with natural antigenic-drift variants of h5n1 high-pathogenicity avian influenza viruses from Indonesia. J Virol. 89(7):3746–3762. [DOI] [PMC free article] [PubMed] [Google Scholar]
- The IUCN Red List of Threatened Species . 2008. Version 2019-3 [Gland (Switzerland)]: IUCN; [accessed 2008 June 30]. www.iucnredlist.org.
- Yu YQ, Mz J, Liu CG, Li KH, Guo ST. 2008. Geographical distribution and vicissitude of argali, Ovis ammon, in China. Biodiv Sci. 16(2):197–204. [Google Scholar]