Complete Mitochondrial Genome Sequence Research Articles

Complete Mitochondrial Genomes and Phylogenetic Analysis of Genus Henricia (Asteroidea: Spinulosida: Echinasteridae).

The genus Henricia is known to have intraspecific morphological variations, making species identification difficult. Therefore, molecular phylogeny analysis based on genetic characteristics is valuable for species identification. We present complete mitochondrial genomic sequences of Henricia longispina aleutica, H. reniossa, and H. sanguinolenta for the first time in this study. This study will make a significant contribution to our understanding of Henricia species and its relationships within the class Asteroidea. Lengths of mitochondrial genomes of the three species are 16,217, 16,223, and 16,194 bp, respectively, with a circular form. These genomes contained 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and a D-loop. The gene order and direction aligned with other asteroid species. Phylogenetic relationship analysis showed that our Henricia species were in a monophyletic clade with other Henricia species and in a large clade with species (Echinaster brasiliensis) from the same family. These findings provide valuable insight into understanding the phylogenetic relationships of species in the genus Henricia.

Characterization of the Complete Mitochondrial Genome of Salassa thespis (Lepidoptera: Saturniidae) and Comparison with Other Lepidoptera Species

There are many species of Lepidoptera, but few complete mitochondrial genomes of Lepidoptera have been included in databases. Here, the complete mitochondrial genome sequence of Salassa thespis was isolated and characterized. It was 15,302 bp in length and contained 13 protein-coding genes (PCGs), two rRNA genes, 22 tRNA genes and an A + T-rich region. Among the 13 PCGs, the initiation codon of cytochrome c oxidase subunit 1 (cox1) was CGA, and the rest were ATN. The cox1 and cox2 genes had an incomplete stop codon T, while the rest terminated with TAA. Codon usage analysis showed that Phe, Ile, Leu and Asn were the most frequent amino acids, while Trp was the least. Like other Lepidopterans, some conserved motifs were found in the A + T-rich region, including a 17 bp poly-T guided by ATAGA, the AT-rich area and a poly-A element. Bayesian inference and maximum likelihood phylogenetic tree analysis based on 13 PCGs of S. thespis confirmed that it belonged to the Saturniidae family and showed the following relationship: (S. thespis + (Rhodinia fugax + Samia canningi)). The enrichment of mitochondrial DNA provides reference information for the study of the evolution and diversity of Lepidoptera insects.

Complete Mitochondrial Genome and Its Phylogenetic Position in Red Algae Fushitsunagia catenata from South Korea.

The mitogenome is an important tool in taxonomic and evolutionary studies. Only a few complete mitogenomes have been reported for red algae. Herein, we reported the complete mitochondrial genome sequence of Fushitsunagia catenata (Harvey) Filloramo, G.V. and Saunders, G.W. 2016, a monospecific genus. The genome was 25,889 bp in circumference and had a strongly biased AT of 70.4%. It consisted of 2 rRNAs, 23 tRNAs, and 24 protein-coding genes (PCGs). nad5 (1986 bp) was the largest and atp9 (231 bp) was the smallest PCG. All PCGs used ATG as an initiation codon and TAA as a termination codon, except TAG, which was the termination codon used in the sdh3, rps3, and rps11 genes. The general structure and gene content of the present findings were almost identical to those of other red algae genomes, particularly those of the Rhodymeniales order. The maximum likelihood analysis showed that F. catenata was closely related to Rhodymenia pseudopalmata. The mitochondrial genome data presented in this study will enhance our understanding of evolution in Rhodophyta species.

The complete mitochondrial genome of freshwater gammarid Gammarus nipponensis (Crustacea: Amphipoda: Gammaridae)

This study presents the complete mitochondrial genome sequence of Gammarus nipponensis, a freshwater crustacean found in the western regions of Honshu, Shikoku and Kyushu in Japan. The entire genome is 16,429 bp in length, encoding a standard set of 13 protein-coding genes, two ribosomal RNA genes and 22 transfer RNA genes, as well as the putative control regions. The mitochondrial genome of G. nipponensis is characterized by a high concentration of A and T nucleotides (67.1%). Notably, the mitogenome contains long TATTTTA repeats in the control region 2 at 686 bp long. This newly available genome information will be useful for studying the evolutionary relationships within the genus Gammarus and for understanding diversification among G. nipponensis populations.

The direction, timing and demography of Popillia japonica (Coleoptera) invasion reconstructed using complete mitochondrial genomes

The Japanese beetle Popillia japonica is a pest insect that feeds on hundreds of species of wild and cultivated plants including important fruit, vegetable, and field crops. Native to Japan, the pest has invaded large areas of the USA, Canada, the Azores (Portugal), Italy, and Ticino (Switzerland), and it is considered a priority for control in the European Union. We determined the complete mitochondrial genome sequence in 86 individuals covering the entire distribution of the species. Phylogenetic analysis supports a major division between South Japan and Central/North Japan, with invasive samples coming from the latter. The origin of invasive USA samples is incompatible, in terms of the timing of the event, with a single introduction, with multiple Japanese lineages having been introduced and one accounting for most of the population expansion locally. The origin of the two invasive European populations is compatible with two different invasions followed by minimal differentiation locally. Population analyses provide the possibility to estimate the rate of sequence change from the data and to date major invasion events. Demographic analysis identifies a population expansion followed by a period of contraction prior to the invasion. The present study adds a time and demographic dimension to available reconstructions.

Sequencing and Analysis of the Complete Mitochondrial Genome of Lentipes ikeae.

We sequenced and analyzed the complete mitochondrial genome of Lentipes ikeae and explored the phylogenetic relationships among Sicydiinae based on mitochondrial genome sequences. The complete mitochondrial genome sequence of L. ikeae was determined using the Illumina HiSeq X Ten sequencing platform, and the gene structural characteristics and base composition were analyzed. Based on the mitochondrial genome sequences of 28 Sicydiinae species published in GenBank and mitochondrial protein-coding genes (PCGs), Acanthogobius flavimanus (Gobionellinae) was selected as an outgroup to construct phylogenetic trees of Sicydiinae using the maximum likelihood and Bayesian inference methods. The mitochondrial genome of L. ikeae (GenBank number: OP764680) has a total length of 16,498 bp and encodes 13 PCGs, 22 transfer RNA genes, two ribosomal RNA genes, and a D-loop (control) region. Gene rearrangement is not observed. The mitochondrial genome of L. ikeae exhibits an AT preference, with AT skew > 0 and GC skew < 0 across the entire genome. The phylogenetic relationships of Sicydiinae based on 13 mitochondrial PCG sequences are Sicydium + (Stiphodon + (Sicyopus + Lentipes)) + Sicyopterus, indicating that Sicydium, Sicyopterus, Lentipes, and Stiphodon are all monophyletic groups.

Characterization of the complete mitochondrial genome of Paecilomyces variotii and comparative evolutionary mitochondriomics of 36 fungi.

Paecilomyces variotii has important economic value in stimulating crop growth, biodegradation, and other aspects. Up to now, there are no research reports on its mitochondrial genome. The mitochondrial genome of Paecilomyces variotii was determined with the next-generation sequencing method (Illumina, NovaSeq), and its characteristics were analyzed using various bioinformatics approaches. The length of complete mitochondrial genome sequence of P. variotii is 40,965bp and consists of 14 protein-coding genes, 2 ribosomal RNA genes, 1 ribosomal protein S3 gene, 26 transport RNA genes. The results of phylogenetics analysis using Bayesian inference and Maximum likelihood methods showed that P. variotii belongs to the Eurotiales order in the Thermoascaceae family, and 9 genera within the Eurotiomycetes class were effectively distinguished with high support rates (bootstrap value > 92% and posterior probabilities > 99%). The analysis of synonymous substitution rates and nonsynonymous substitution rates indicated that the Ka/Ks values of the 14 PCGs in the mitochondrial genomes of the two orders in the Eurotiomycetes class ranged from 0 to 0.4333. This study revealed the structural and sequence information characteristics of the mitochondrial genome of P. variotii, and the phylogenetic results strongly support its classification within the family Thermoascaceae, consistent with traditional morphological taxonomy studies. The 14 PCGs in the mitochondrial genomes of the two orders in the Eurotiomycetes class are subject to strong purifying (negative) selection. The results of this research provides an important molecular basis for the development of genomics, evolutionary genetics and molecular markers of P. variotii in the future.

Comparative Analysis and Phylogenetic Study of Dawkinsia filamentosa and Pethia nigrofasciata Mitochondrial Genomes.

Smiliogastrinae are recognized for their high nutritional and ornamental value. In this study, we employed high-throughput sequencing technology to acquire the complete mitochondrial genome sequences of Dawkinsia filamentosa and Pethia nigrofasciata. The gene composition and arrangement order in these species were similar to those of typical vertebrates, comprising 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and 1 non-coding region. The mitochondrial genomes of D. filamentosa and P. nigrofasciata measure 16,598 and 16,948 bp, respectively. Both D. filamentosa and P. nigrofasciata exhibit a significant preference for AT bases and an anti-G bias. Notably, the AT and GC skew values of the ND6 gene fluctuated markedly, suggesting that the selection and mutation pressures on this gene may differ from those affecting other genes. Phylogenetic analysis, based on the complete mitochondrial genomes of 23 Cyprinidae fishes, revealed that D. filamentosa is closely related to the sister group comprising Dawkinsia denisonii and Sahyadria chalakkudiensis. Similarly, P. nigrofasciata forms a sister group with Pethia ticto and Pethia stoliczkana.

The complete mitochondrial genome of Tauraco livingstonii (Musophagidae: Tauraco)

Livingstone’s turaco, Tauraco livingstonii, belongs to the family Musophagidae. In this study, we obtained the complete mitochondrial genome sequence of Livingstone’s turaco by high-throughput sequencing technology and constructed a phylogenetic tree. It was found that the mitochondria of this species are 19,015 bp in length and contain a total of 37 genes, comprising 13 protein-coding genes, 22 tRNA genes, and 2 rRNA genes. The base composition of the mitochondrial genome is 31.61% A, 24.22% T, 30.64% C, and 13.52% G, with a GC content of 44%. Notably, an intriguing phenomenon of mitochondrial genome rearrangements was observed, characterized by the duplication of the tRNA Glu-L-CR gene order. In addition, the results of the phylogenetic tree analysis shed light on the taxonomic position of Livingstone’s turaco and supported the taxonomy of Otidimorphae. The study provides a basis for future phylogenetic and taxonomic investigations of Musophagiformes.

Complete mitochondrial genome of Basilepta melanopus Lefèvre, 1893 (coleoptera: chrysomelidae: eumolpinae), a tea pest from Southern China

The tea pest, Basilepta melanopus Lefèvre 1893 (Chrysomelidae), belongs to the subfamily Eumolpinae. In this study, the complete mitochondrial genome sequence of B. melanopus from southern China was sequenced using the next-generation sequencing technique, assembled, and annotated using bioinformatics tools. The complete mitochondrial genome was 15,905 bp in length. The overall GC content was 22.51%, in which the percentages for the bases A, T, C, and G were 41.23%, 36.26%, 8.92%, and 13.59%, respectively. Thirty-seven genes were predicted, including 13 protein-coding, 22 transfer RNA, and two ribosomal RNA genes. Phylogenetic analysis based on the complete mitochondrial genome sequences of 18 Chrysomelidae taxa revealed that B. melanopus was closely related to Basilepta fulvipes.

Comparative Analysis of Mitochondrial Genome in Fishes

Mitochondrial genome is circular double stranded DNA molecule in most of the eukaryotic organism which is ubiquitously present in all cells as it associated with production of energy. The number of complete mitochondrial genomes sequenced has been increasing day by day. Till date, the complete mitochondrial genome more than 2000 fish species can be retrieved from the NCBI GenBank. Like other vertebrates, fish mitochondrial genome contains 37 genes which include 22 tRNAs, 2 rRNAs (12S &amp; 16S), 13 protein coding genes and one noncoding regions (Control region). The length of fish mitochondrial genome varies based on the size of noncoding region (CR). The complete mitochondrial genome sequence length varies from species to species. This comparison of genome sequences envisage the variations are mostly in the control region as it is highly evolved than other genes of mitochondria. Its mutation rate is very high. Therefore more numbers of indels and intergenic sequences are found. It may be due to the genetic drift, relaxed functional constraint and reduced selection pressure in the evolution of fish mitogenomes.

Climate-driven mitochondrial selection in lacertid lizards.

The mitochondrion, which is an intracellular organelle responsible for most of the energy-producing pathways, can have its genome targeted for climate-driven selection. However, climate-driven mitochondrial selection remains a sparsely studied area in reptiles. Here, we reported the complete mitochondrial genome sequence of a lacertid lizard (Takydromus intermedius) and used mitogenomes from 54 species of lacertid lizards to study their phylogenetic relationships and to identify the mitochondrial genes under positive selection by climate. The length of the complete mitochondrial genome sequence of T. intermedius was 17,713 bp, which was within the range of lengths (17,224-18,943) ever reported for Takydromus species. The arrangement of mitochondrial genes in T. intermedius was the same as in other congeneric species. The 54 lacertid species could be divided into three geographically and climatically different clades. We identified three mitochondrial genes (ATP6, ATP8, and ND3) under positive selection by climate, and found that isothermality, temperature seasonality, precipitation of wettest month, and precipitation seasonality were the most important climatic variables contributing to the gene selection.

Analysis of the mitochondrial genome and phylogenetic relationships of Mong chicken

In this study, the complete nucleotide sequence of the mitochondrial genome of the Mong chicken and an indigenous chicken breed of Vietnam, was determined by the Sanger sequencing method, structurally analysed and used to evaluate the phylogenetic relationship with different chicken breeds. The complete nucleotide sequence data of the Mong chicken’ mitochondrial genome was registered on GenBank with the accession number OR643716. The Mong chicken’ mitochondrial genome has a size of 16785 base pair (bp) and includes 22 transfer RNA genes, two ribosomal RNA genes, 13 protein-coding genes, and one non-coding control region (D-loop). A, T, G, and C nucleotide proportions were 30.28, 23.76, 13.48, and 32.48%, respectively. Results of the analysis of phylogenetic relationships based on 33 complete mitochondrial genome sequences showed that the Mong chicken has evolutional origin from the red junglefowl subspecies Gallus gallus spadiceus. The Mong chicken is in close relationship with the Dong Tao chicken and Cao Son dwarf chicken in Vietnam, Rugao yellow chicken and Xiaoxiang chicken in China.

Mitogenomic evidence of population differentiation of thorny skate, Amblyraja radiata, in the North Atlantic.

Management of thorny skate (Amblyraja radiata) in the Northwest Atlantic has posed a conservation dilemma for several decades due to the species' lack of response to strong conservation efforts in the US Gulf of Maine and the Canadian Scotian Shelf, confusion over the relationship between two reproductive size morphs of differing life histories that are sympatric in the Northwest Atlantic, and conflicting data on regional population connectivity throughout the species' broader range. To better assess potential A. radiata regional population differentiation and genetic links to life-history variation, we analysed complete mitochondrial genome sequences from 527 specimens collected across the species' North Atlantic geographic range, with particular emphasis on the Northwest Atlantic region. A high level of genetic diversity was evident across the North Atlantic, but significant genetic differentiation was identified between specimens inhabiting the Northwest (Gulf of Maine and Newfoundland) and Northeast (Greenland, Iceland, North Sea, and Arctic Circle) Atlantic. In the Northwest Atlantic, significant differentiation between the Gulf of Maine and Newfoundland regions was revealed; however, the overall level of differentiation was very low. No genetic difference was identified between the large and small reproductive morphs. The results of this study advance our understanding of A. radiata population structure in the North Atlantic but do not resolve all the questions confounding our understanding of the species' biology and evolutionary history.

The complete mitochondrial genome of Poraniopsis inflata (Asteroidea: Valvatida: Poraniidae) from Dokdo Island, Korea

This study presents the complete mitochondrial genome sequence of Poraniopsis inflata, providing valuable information on its genetic and taxonomic studies. Through next-generation sequencing, we successfully obtained the complete mitogenome of P. inflata, spanning a length of 16,322 bp. This genome structure encompasses 13 protein-coding genes (PCGs), 22 transfer RNA genes, and two ribosomal RNA genes. The phylogenetic analysis, based on a dataset of 13 PCG sequences, illuminated the phylogenetic relationships of P. inflata with other species of class Asteroidea and a species of echinoderm classes. The maximum likelihood phylogenetic tree showed that P. inflata closely clustered with Linckia laevigata. By revealing its mitochondrial genome and positioning it within the Asteroidea lineage, this study provides insights into the phylogenetic context of P. inflata.

The complete mitochondrial genome of Gobio huanghensis (Cypriniformes: Cyprinidae) in the Yellow River, China

Gobio huanghensis, a member of the eponymous genus within the Cyprinidae, family of the Cypriniformes order, is an endemic fish species found exclusively in the upper reaches of the Yellow River, spanning from Yinchuan to Lanzhou. This study presents the first comprehensive report of the complete mitochondrial genome sequence of G. huanghensis, encompassing 16,604 base pairs (bp) with a nucleotide composition of 26.3% cytosine (C), 17.6% guanine (G), 29.4% adenine (A), and 26.7% thymine (T). In congruence with other species in the Gobio genus, its mitochondrial genome comprises 37 genes, including two ribosomal RNA genes, 13 protein-coding genes (PCGs), and 22 transfer RNA genes. Notably, COX1 initiates with the start codon GTG, distinct from the typical ATG start codon of other PCGs. The mitogenome exhibits four types of stop codons: TAA, TAG, TA-, and T--. Phylogenetic analyses, grounded in complete mitochondrial sequences, position G. huanghensis at the forefront of one of two major clusters within the genus Gobio, corroborating existing morphological classifications. These findings offer valuable theoretical insights for the taxonomic classification, conservation, and population genetics of G. huanghensis.

The complete mitochondrial genome of the tropical sea urchin Tripneustes gratilla (Linnaeus, 1758) with two spine colors

The complete mitochondrial genomes of two spine-color individuals, red and white, of the tropical sea urchin species Tripneustes gratilla (Linnaeus, 1758) were sequenced on Illumina system platform. The red-spined species had a genome size of 15,774 bp, while the white-spined species had a genome size of 15,723 bp. Both genomes contained 13 protein-coding genes, 2 rRNA genes, and 22 tRNA genes. The GC composition in both species was above 40%. In order to investigate the phylogenetic relationships of two different spine-color individuals, a comprehensive analysis was conducted using eight complete mitochondrial genomic sequences of the genus Tripneustes on the software MEGA X. It was observed that the two spine color types of T. gratilla species showed a high similarity of 98.91%. However, different color-spined species of T. gratilla were found in separate branches of the phylogenetic tree of the same sea urchin species.

Structural Analysis and Phylogenetic Relationship of a Lepidopteran Scopelodes kwangtungensis Based on its Complete Mitochondrial Genome Sequence

Structural Analysis and Phylogenetic Relationship of a Lepidopteran Scopelodes kwangtungensis Based on its Complete Mitochondrial Genome Sequence

The complete mitochondrial genome and phylogenetic analysis of hydrozoan jellyfish Eirene ceylonensis (Cnidaria, Hydrozoa, Eirenidae) in the coastal sea of Qinhuangdao, China

Eirene ceylonensis, a hydrozoan jellyfish species with a complex polymorphic life cycle, is widely distributed in the Chinese coastal sea. In this study, we conducted sequencing and analysis of the first complete mitochondrial genome of E. ceylonensis, obtained from the coastal sea of Qinhuangdao, China. The linear mitochondrial genome is 14,997 bp in length with the overall AT content being 72.8%, encoding 13 protein-coding genes (PCGs), two transfer RNA (tRNA) genes (tRNA-Met and tRNA-Trp) and two ribosomal RNA (rRNA) genes (rrnS and rrnL). Phylogenetic analysis of 13 PCGs suggests that the E. ceylonensis is closely related to Laomedea flexuosa. The availability of the complete mitochondrial genome of E. ceylonensis will be useful for studying the evolutionary relationships of hydrozoan jellyfish species.

The complete mitochondrial genome of the Kandelia obovata Sheue, H.Y.Liu & J.W.H.Yong (Rhizophoraceae)

Kandelia obovata Sheue, H.Y.Liu & J.W.H.Yong is one of the most cold-resistant true mangrove species, and it is widely distributed from the South China Sea to southern Japan. In the current study, the complete mitochondrial genome sequence of K. obovata was assembled using Illumina reads. It is the first mitochondrial genome of the Kandelia genus within the family Rhizophoraceae to be sequenced. The mitochondrial genome size is 312,146 bp with a total of 49 predicted genes, including 29 protein-coding genes, 17 transfer RNA genes, and 3 ribosomal RNA genes. The overall GC content of the genome is 41.87%. A phylogenetic tree constructed using nine complete mitochondrial genomes revealed that K. obovata is more closely related to Bruguiera species. This study enriches the plastid genome of Kandelia, furnishing valuable genetic insights for the investigation of evolutionary and population genetics in Kandelia and other mangrove species.