The complete mitochondrial DNA sequence of the cape hare Lepus capensis pamirensis

Chromosome-level genome assembly of Nibea coibor using PacBio HiFi reads and Hi-C technologies

Nibea coibor belongs to Sciaenidae and is distributed in the South China Sea, East China Sea, India and the Philippines. In this study, we sequenced the DNA of a male Nibea coibor using PacBio long-read sequencing and generated chromatin interaction data. The genome size of Nibea coibor was estimated to be 611.85~633.88 Mb based on k-mer counts generated with Jellyfish. PacBio sequencing produced 29.26 Gb of HiFi reads, and Hifiasm was used to assemble a 627.60 Mb genome with a contig N50 of 10.66 Mb. We further found the canonical telomeric repeats "TTAGGG" to be present at the telomeres of all 24 chromosomes. The completeness of the assembly was estimated to be 98.9% and 97.8% using BUSCO and Merqury, respectively. Using the combination of ab initio prediction, protein homology and RNAseq annotation, we identified a total of 21,433 protein-coding genes. Phylogenetic analyses showed that Nibea coibor and Nibea albiflora are closely related. The results provide an important basis for research on the genetic breeding and genome evolution of Nibea coibor.

The complete mitochondrial genome of the 'Zacatuche' Volcano rabbit (Romerolagus diazi), an endemic and endangered species from the Volcanic Belt of Central Mexico

BACKGROUND

The 'Zacatuche', 'Teporingo', or Volcano rabbit (Romerolagus diazi) belongs to the family Leporidae, is an endemic species restricted to the Central part of the Trans-Mexican Volcanic Belt, and is considered 'endangered' by the IUCN Red List of Threatened Species.

METHODS AND RESULTS

This study reports, for the first time, the complete mitochondrial genome of R. diazi and examined the phylogenetic position of R. diazi among other closely related co-familiar species using mitochondrial protein-coding genes (PCGs). The mitogenome of R. diazi was assembled from short Illumina 150 bp pair-end reads with a coverage of 189x. The AT-rich mitochondrial genome of R. diazi is 17,400 bp in length and is comprised of 13 PCGs, two ribosomal RNA genes, and 22 transfer RNA genes. The gene order observed in the mitochondrial genome of R. diazi is identical to that reported for other leporids. Phylogenetic analyses based on PCGs support the basal position of Romerolagus within the Leporidae, at least when compared to the genera Oryctolagus and Lepus. Nonetheless, additional mitochondrial genomes from species belonging to the genera Bunolagus, Sylvilagus, and Pronolagus, among others, are needed before a more robust conclusion about the derived vs basal placement of Romerolagus within the family Leporidae can be reached based on mitochondrial PCGs.

CONCLUSIONS

This is the first genomic resource developed for R. diazi and it represents a tool to improve our understanding about the ecology and evolutionary biology of this iconic and endangered species.

Complete mitochondrial genome sequence of Lepus yarkandensis Günther, 1875 (Lagomorpha, Leporidae): characterization and phylogenetic analysis

Lepusyarkandensis is a national second-class protected animal endemic to China and distributed only in the hot and arid Tarim Basin in Xinjiang. We sequenced and described the complete mitogenome of L.yarkandensis to analyze its characteristics and phylogeny. The species’ DNA is a 17,047 bp circular molecule that includes 13 protein-coding genes (PCGs), two rRNA genes, 22 tRNA genes, and one control region. The overall base composition was as follows: A, 31.50%; T, 29.40%; G, 13.30% and C, 25.80%, with a high A+T bias of 60.9%. In the PCGs, ND6 had deviation ranges for AT skew (–0.303) and GC skew (0.636). The Ka/Ks values of ND1 (1.067) and ND6 (1.352) genes were >1, indicating positive selection, which might play an important role in the adaptation of L.yarkandensis to arid and hot environments. The conserved sequence block, the central conserved domain, and the extended termination-associated sequences of the control region and their features were identified and described. The phylogenetic tree based on the complete mitogenome showed that L.yarkandensis was closely related to the sympatric Lepustibetanuspamirensis. These novel datasets of L.yarkandensis can supply basic data for phylogenetic studies of Lepus spp., apart from providing essential and important resource for further genetic research and the protection of this species.

The complete mitochondrial DNA sequence of Kashgarian loach (Triplophysa yarkandensis) from Bosten Lake

Triplophysa yarkandensis is a specific cobitidae species that is endemic to Xinjiang Tarim River basin, China. The complete mitochondrial genome sequence of T. yarkandensis from Bosten Lake was determined in this study (Accession number MN821008). The mitogenome (16,552 bp) consists of 22 tRNA genes, 2 ribosomal RNA genes, 13 protein-coding genes, and 1 control region (D-loop region). The complete mitochondrial genome sequence of the T. yarkandensis provides an important data set for further study in genetic mechanism and classification.

The complete mitochondrial DNA sequence of Yimeng wool rabbit

Yimeng wool rabbit is a national breed of geographical indication in China. The complete mitochondrial genome sequence of Yimeng wool rabbit was first determined in this study (Accession number MN296708). The mitogenome (16,740 bp) consists of 22 tRNA genes, 2 ribosomal RNA genes, 13 protein-coding genes, and 1 control region (D-loop region). The complete mitochondrial genome sequence of the Yimeng wool rabbit enriches data resource for further study in genetic mechanism and classification.

The complete mitochondrial DNA sequence of the Chinese red pika (Ochotona erythrotis)

In this study, we undertook the first complete Ochotona erythrotis mitochondrial genome. The genome sequence was 16,663 bp in length, including the typical structure of 22 transfer RNA genes, 13 protein-coding genes, 2 ribosomal RNA genes, and the non-coding control region. The overall base composition of O. erythrotis mitogenome is 31.8% A, 26.0% T, 28.6% G, and 13.6% C, with a high A + T content of 57.8%.

The complete mitochondrial DNA sequence of Xinjiang arctic grayling Thymallus arcticus grubei

Thymallus arcticus grubei is a specific grayling species that naturally occurs in the Xinjiang Irtysh River basin, China. The complete mitochondrial genome of The Xinjiang arctic grayling T. arcticus grubei was first determined (Accession number LC168675), with a total length of 16,658 nucleotides, of which 15,587 nucleotides are coding DNA, and 1071 nucleotides are non-coding DNA. It has the common feature with those of other grayling with respect to genome structure and gene arrangement. It contained 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer tRNA genes, and 1 control region (D-loop region). The complete mitochondrial genome of Xinjiang arctic grayling T. arcticus grubei provides an important data set for further study on its classification.