SEARCH · PubMed Health

Results for “Mitogenome”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

PubMed2026

A New Species of Eucnemidae (Coleoptera: Elateroidea) with Its Complete Mitogenome and Mitogenome-Based Phylogenetic Analysis.

We describe Microrhagus ziwulingensis Muona & Meng, sp. nov., from China. The genus Microrhagus Dejean, 1833, was previously represented in China by only two species. We sequenced and assembled the complete mitogenome of M. ziwulingensis (GenBank accession OK143440), which encoded 13 protein-coding genes (PCGs), 2 ribosomal RNA genes (rRNAs), 22 transfer RNA genes (tRNAs), and a putative control region with a total length of 15,843 bp. Overall, 36 species of Elateroidea were collected as the ingroup (for six of these species, two sequences of the same species submitted by different submitters were used). Eight species of Buprestoidea served as the outgroup. We constructed phylogenetic trees using maximum likelihood (ML) and Bayesian inference (BI) methods based on 13 protein-coding genes (PCGs) from mitochondrial genomes. The phylogenetic trees showed that all families within the superfamily Elateroidea, which was used as the ingroup, formed monophyletic groups. The topology differed from previous studies, showing that Rhagophthalmidae and Lampyridae formed a sister clade, and that Phengodidae + Lycidae, with Cantharidae, formed a sister clade. These discrepancies should be attributed to the use of a single type of molecular marker and the intense shortage of available sampling. This also indicates that mitochondrial genomic research on Eucnemidae, and even on the superfamily Elateroidea, still needs further expansion.

Microrhagus↗

PubMed2026

Mitogenomic phylogeny of the aquatic subterranean Bathynellacea (Crustacea, Malacostraca) and implications for the monophyly of Syncarida.

The crustacean order Bathynellacea is a specialized monophyletic lineage restricted to aquatic subterranean environments and comprises approximately 340 extant species from three families. Despite advances in sequencing technologies that have significantly increased the number of sequenced crustacean mitogenomes, no bathynellacean mitogenomes have been reported to date. In this study, we report the first complete mitogenomes for Bathynellacea-Allobathynella sp., Arisubathynella cheongmiensis, Hangangbathynella mihoensis (Parabathynellidae), and Bathynella cf. rufa (Bathynellidae)-from two families. These mitogenomes, ranging from 14,422 to 16,645 bp in length, are characterized by extensive gene rearrangements, pronounced compositional biases, and accelerated evolutionary rates. Phylogenetic analyses based on malacostracan mitogenomic data strongly support the monophyly of Bathynellacea. However, the exceptionally long branches separating bathynellacean taxa suggest that extensive morphological simplification, driven by parallel adaptations to subterranean environments, may mask the ancestral diagnostic signals required to resolve their deep-level relationships. Most notably, our results indicate that the two extant orders within the superorder Syncarida-Bathynellacea and Anaspidacea-are phylogenetically distant, supporting the polyphyly of Syncarida. This suggests that their shared morphological features (e.g., the absence of a carapace and the loss of the mandibular lacinia mobilis) are likely products of convergent evolution rather than common ancestry. Our study provides mitogenomic resources for Bathynellacea and underscores the necessity of mitogenomic evidence in reassessing the taxonomic status of subterranean crustacean lineages.

Animals↗

PubMed2025

A Million Years of Mammoth Mitogenome Evolution.

The genomic study of specimens dating to the Early and Middle Pleistocene (EP and MP), a period spanning from 2.6 million years ago (Ma) to 126 thousand years ago (ka), has the potential to elucidate the evolutionary processes that shaped present-day biodiversity. Obtaining genomic data from this period is challenging, but mitochondrial DNA, given its higher abundance compared to nuclear DNA, could play an important role to understand evolutionary processes at this time scale. In this study, we report 34 new mitogenomes, including two EP and nine MP mammoth (Mammuthus spp.) specimens from Siberia and North America and analyze them jointly with >200 publicly available mitogenomes to reconstruct a transect of mammoth mitogenome diversity throughout the last million years. We find that our EP mitogenomes fall outside the diversity of all Late Pleistocene (LP) mammoths, while those derived from MP mammoths are basal to LP mammoth Clades 2 and 3, supporting an ancient Siberian origin of these lineages. In contrast, the geographical origin of Clade 1 remains unresolved. With these new deep-time mitogenomes, we observe diversification events across all clades that appear consistent with previously hypothesized MP and LP demographic changes. Furthermore, we improve upon an existing methodology for molecular clock dating of specimens >50 ka, demonstrating that specimens need to be individually dated to avoid biases in their age estimates. Both the molecular and analytical improvements presented here highlight the importance of deep-time genomic data to discover long-lost genetic diversity, enabling better assessments of evolutionary histories.

Animals↗

PubMed2026

Mitogenomic and phylogenomic analyses identify a cohesive Western Atlantic lineage within the Narcine complex (Torpediniformes: Narcinidae).

BACKGROUND: Accurate species delimitation within electric rays of the genus Narcine has been hindered by overlapping morphological characters and limited molecular resolution in previous single-locus studies. This study aims to evaluate phylogenetic relationships and species boundaries within the Narcine species complex across the Western Atlantic using complete mitochondrial genomes. METHODS AND RESULTS: Seven complete mitogenomes were newly assembled from individuals representing distinct morphotypes sampled across geographically widespread Western Atlantic localities and analyzed together with publicly available reference sequences. Mitochondrial protein-coding genes (PCGs) were examined using concatenated nucleotide and amino acid datasets under partitioned maximum-likelihood frameworks. Both approaches recovered highly congruent topologies, consistently supporting a single, well-defined western Atlantic mitochondrial lineage with low internal divergence (0.04-2.13%). Species delimitation analyses based on multiple methods yielded partially congruent results but consistently identified a dominant lineage encompassing all Atlantic samples. In contrast, two Colombian reference mitogenomes formed a separate and highly divergent lineage relative to the Atlantic group, despite showing moderate divergence between them. Comparative mitogenomic analyses revealed conserved genome organization, nucleotide composition bias, codon usage, and transfer RNA (tRNA) structures. All PCGs evolved under strong purifying selection, with Ka/Ks ratios well below unity. CONCLUSIONS: These results support mitochondrial genetic continuity across the Western Atlantic Narcine populations and do not provide mitochondrial evidence for multiple evolutionary lineages within the Western Atlantic. The marked mitochondrial divergence of Colombian reference mitogenomes highlights potential issues in sequence attribution and underscores the importance of data curation. Overall, complete mitochondrial genomes provide a robust framework for species delimitation and future integrative taxonomic assessments within Narcine.

Animals↗

PubMed2024

Complementing aculiferan mitogenomics: comparative characterization of mitochondrial genomes of Solenogastres (Mollusca, Aplacophora).

BACKGROUND: With the advances in high-throughput sequencing and bioinformatic pipelines, mitochondrial genomes have become increasingly popular for phylogenetic analyses across different clades of invertebrates. Despite the vast rise in available mitogenomic datasets of molluscs, one class of aplacophoran molluscs - Solenogastres (or Neomeniomorpha) - is still neglected. RESULTS: Here, we present six new mitochondrial genomes from five families of Solenogastres (Amphimeniidae, Gymnomeniidae, Proneomeniidae, Pruvotinidae, Simrothiellidae), including the first complete mitogenomes, thereby now representing three of the four traditional orders. Solenogaster mitogenomes are variable in size (ranging from approximately 15,000 bp to over 17,000 bp). The gene order of the 13 protein coding genes and two rRNA genes is conserved in three blocks, but considerable variation occurs in the order of the 22 tRNA genes. Based on phylogenetic analyses and reconstruction of ancestral mitochondrial genomes of Aculifera, the position of (1) trnD gene between atp8 and atp6, (2) trnT and P genes between atp6 and nad5, and (3) trnL1 gene between G and E, resulting in a 'MCYWQGL1E'-block of tRNA genes, are all three considered synapomorphies for Solenogastres. The tRNA gene block 'KARNI' present in Polyplacophora and several conchiferan taxa is dissolved in Solenogastres. CONCLUSION: Our study shows that mitogenomes are suitable to resolve the phylogenetic relationships among Aculifera and within Solenogastres, thus presenting a cost and time efficient compromise to approach evolutionary history in these clades.

Genome, Mitochondrial↗

PubMed2026

Comparative mitogenomics of Ocnus glacialis reveals lineage-specific evolutionary rates and complex gene rearrangements in Dendrochirotida.

The order Dendrochirotida (Class Holothuroidea) is a species-rich echinoderm group, yet its internal evolutionary history remains poorly resolved due to limited mitogenomic resources. In this study, we characterized the first complete mitochondrial genome of Ocnus glacialis and conducted comparative analyses to elucidate its phylogenetic position and molecular evolutionary patterns. The circular mitogenome of O. glacialis is 16,776 bp in length, containing the canonical set of 37 genes. Among the analyzed dendrochirotids, O. glacialis exhibited the highest A + T content (70.88%) and a near-zero AT-skew, a compositional profile often linked to lineage-specific evolution in specialized environments. Selection pressure analyses, including branch-model tests, revealed that these compositional features are associated with relaxed purifying selection and an accelerated rate of sequence evolution. Branch-site analyses further identified specific codon sites in cytb, nad2, nad4l, nad5, and nad6 under positive or relaxed constraints. Structurally, O. glacialis displayed the most complex gene rearrangement pattern among the studied species, characterized by multiple tandem duplication-random loss (TDRL) events and extensive intergenic sequences. Furthermore, divergence time estimation suggests that these structural and compositional shifts occurred in tandem with the lineage's diversification. We propose that these mitogenomic signatures reflect a synergistic outcome of habitat transition toward Arctic cold-water and deep-sea environments, coupled with demographic factors such as reduced effective population sizes inherent to its benthic life history. By resolving taxonomic uncertainties, this study provides a robust temporal and molecular framework for understanding the evolutionary history and ecological diversification of the Ocnus lineage.

Animals↗

PubMed2025

Ancient Mitogenomes Reveal the Maternal Genetic History of East Asian Gray Wolves (Canis lupus).

The gray wolf (Canis lupus) is the only wild ancestor of dogs (Canis lupus familiaris) and serves a crucial role in understanding the highly controversial issue of dog origins. Recently, ancient DNA studies on gray wolves from different regions of the Eurasian continent have achieved significant breakthroughs, providing important clues about the dog origins. As one of the potential origin areas for dogs, East Asia has seen some research on ancient dogs; however, reports related to gray wolves remain limited. In this study, we sequenced seven new mitogenomes of ancient gray wolves from Northern China, integrating them with 497 ancient and modern canid mitogenomes from published data. Our results reveal the following: (1) East Asian gray wolves have maintained high genetic diversity from ancient times to the present; (2) multiple haplogroup A gray wolves from Northern China support the hypothesis that Northeastern Eurasia is a core region for dog origins; (3) a deep gray wolf lineage in East Asia has been identified in this study; (4) different mitogenomes concentrated at the Jinchankou site indicate that admixture may have frequently occurred in the northeastern edge of the Tibetan Plateau. These findings enhance our understanding of the maternal genetic history of gray wolves in East Asia.

Animals↗

PubMed2026

Introgression among maternal lineages inferred from complete mitogenomes and molecular dating helps resolve phylogeography of European roe deer.

BACKGROUND: The European roe deer (Capreolus capreolus) is one of the most widespread ungulates in Europe, with a phylogeographic structure mainly shaped by Pleistocene glacial cycles and secondary contacts with the Siberian roe deer (C. pygargus). METHODS: We sequenced 52 complete mitogenomes of C. capreolus from Slovenia, Poland and France, and combined them with 24 publicly available sequences of C. capreolus and C. pygargus, yielding an alignment of 76 genomes representing 59 haplotypes (42 from C. capreolus and 17 from C. pygargus). Phylogeographic structure was assessed using a median-joining network, and divergence times were estimated using a time-calibrated Bayesian phylogeny based on mitochondrial coding regions, incorporating published ancient C. pygargus mitogenomes. We additionally screened mitochondrial protein-coding genes for selection. RESULTS: The haplotype network recovered the three major European roe deer clades (Eastern, Central, and Western) and detected Central-clade haplotypes in France. Two Polish haplotypes (Cp9 and Cp10), detected in C. capreolus, clustered within the C. pygargus mitochondrial lineage, supporting mitochondrial introgression. Time-calibrated phylogenies placed introgressed haplotypes within established C. pygargus lineages. Selection analyses provided limited evidence for episodic positive selection restricted to a small number of codons. CONCLUSIONS: Whole mitogenomes improve resolution of roe deer phylogeography and reveal introgressed maternal lineages, while time-calibrated phylogenies and selection tests add evolutionary context for interpreting mtDNA diversity in genus Capreolus.

Animals↗

PubMed2026

Mitogenome assembly and phylogenetic relationships of Phalaris arundinacea.

INTRODUCTION: As a perennial herb of Poaceae, Phalaris arundinacea plays key roles in grazing, production, and soil and water conservation because of its well-developed rhizomes and seed dispersal. We assembled and annotated the first mitogenome of P. arundinacea to support evolutionary and taxonomic research. METHODS: We assembled and annotated the first complete mitochondrial genome of P. arundinacea by integrating Illumina short reads with Nanopore long reads via a hybrid assembly strategy. The genome architecture was comprehensively characterized, encompassing codon usage bias, repetitive sequence organization, and inter-organellar genetic exchange with the chloroplast genome. RESULTS AND DISCUSSION: Assembly of the P. arundinacea mitogenome revealed two circular structures with a combined length of 526,717 bp. The genome comprised a set of 37 protein-coding genes (PCGs), 27 tRNAs, and 8 rRNAs, with the rRNA genes exhibiting full assembly (100% coverage). The mitochondrial genome contained 154 forward and 164 palindromic repeats, along with 25 tandem repeats and 124 simple sequence repeats (SSRs). Notably, 102 SSRs were distributed on contig1, predominantly in tetrameric form. Furthermore, 376 RNA editing sites were predicted. A total of 104 fragments were integrated into the mitochondrial genome from the chloroplast, amounting to 55,866 bp of transferred sequence. Finally, phylogenetic analysis of 28 plant mitogenomes placed P. arundinacea closest to species within the genus Poa (P. chaixii and P. pratensis). Comparative analysis of non-synonymous-to-synonymous substitution rate (Ka/Ks) ratios across divergent species revealed that the mitochondrial genome of P. arundinacea underwent stabilizing evolutionary dynamics, characterized by predominant purifying selection with several lineage-specific variations in selective pressure. Our findings support the close phylogenetic relationship between P. arundinacea and species of the genus Poa and provide a reference mitochondrial genome resource for future comparative studies within Phalaris that incorporate broader taxon sampling. These results support deeper phylogenetic investigations of P. arundinacea and facilitate future work on its germplasm characterization and applied use.

Phalaris arundinacea↗

PubMed2026

Scalable assembly of Ascaris mitogenomes from whole-genome data reveals a novel clade.

The genus Ascaris is an important group of giant parasitic roundworms, infecting over 700 million people globally and causing substantial economic losses in domestic pigs. Whilst species of Ascaris are morphologically indistinguishable, analysis of mitochondrial loci has revealed three clades (A, B, C) broadly associated with host species and geographic distribution. The diversity within these lineages may expand with the addition of further genomic data. Here, we present a bioinformatic framework for de novo assembly of complete mitochondrial genomes (mitogenomes) from low-coverage whole-genome data through host-read depletion or mtDNA read enrichment, followed by mtDNA-specific assembly. Our approach yielded 149 high-quality Ascaris mitogenome assemblies, enabling the study of population-level diversity, including the identification of a novel clade (Clade D, designated here) associated with human samples from Ethiopia. Our analysis further revealed Clade C to comprise of pig-derived samples from Europe based on characterisation of worms isolated in Germany. The methods described here provide a scalable framework for mitogenome reconstruction with insights into roundworm population-genomic and phylogenetic studies.

Animals↗

PubMed2026

Whole mitogenome profile of Pelung and Sentul chickens to reveal potency of Indonesian livestock genetic resources.

Native chickens are essential genetic resources in Indonesia, providing economic, cultural, and nutritional value with strong adaptability to local environments. Among these native chickens, Sentul and Pelung are recognized as national genetic resources due to dual-purpose and ornamental traits, respectively, but their whole mitogenome characterization remains limited. Therefore, this study aimed to assemble and analyze the whole mitogenome of Sentul and Pelung chickens as well as perform a comparison with 35 additional genomes from domestic chickens and jungle fowls across Asia. The experiment was carried out using next-generation sequencing and bioinformatics-based genome assembly and analysis. The results showed that both Sentul and Pelung genomes were 16,784 bp in length and contained the typical mitochondrial gene composition, including 13 protein-coding genes (PCGs), 22 transfer ribonucleic acids (tRNAs), two ribosomal ribonucleic acids (rRNAs), and a control region (D-loop). Furthermore, comparative analysis identified five single-nucleotide polymorphisms (SNPs) distinguishing the two breeds, located in ND1, COX1, COX2, ND4, and the D-loop region. Phylogenetic reconstruction based on whole mitochondrial sequences showed that Sentul and Pelung chickens belong to haplogroup D, alongside other native breeds and red jungle fowls from Indonesia and the Philippines.

Genetic diversity↗

PubMed2026

Mitogenomic Insights Into the Population Structure and Demographic History of Tree Shrews (Tupaia belangeri) in China.

The northern tree shrew (Tupaia belangeri) exhibits significant morphological and geographical variations, but its evolutionary history and subspecies boundaries remain controversial. Here, we analyzed the complete mitochondrial genomes of 63 individuals, representing 12 populations in China to study phylogenetic relationships, genetic diversity, and population history. Phylogenetic analysis consistently restored four mitochondrial branches with strong geographic structures and significant differences. The three lineages correspond to geographically restricted subspecies (T. b. tonquinia, T. b. modesta, and T. b. gaoligongensis), while individuals assigned to several traditional subspecies cluster in a broad mainland lineage (T. b. chinensis, T. b. yunalis, and T. b. yaoshanensis). The divergence time estimate places the origin of the main lineage in the Miocene, consistent with major tectonic and geomorphological events. Demographic analysis revealed different population histories, including varying degrees of expansion in recent continental and island lineages, as well as the long-term stability of T. b. gaoligongensis. Genetic diversity varied markedly among lineages, with the highest diversity observed in the T. b. gaoligongensis and the lowest diversity observed in the T. b. modesta. These findings demonstrate that landscape complexity and demographic history are key drivers of evolutionary diversification in T. belangeri, challenging classical morphology-based subspecies classifications and underscoring the need for comprehensive sampling across both domestic and international ranges.

Tupaia belangeri↗

PubMed2023

The complete mitogenome of Paratanakia chii (Cypriniformes; Cyprinidae).

Paratanakia chii is a bitterling fish of the genus Paratanakia, subfamily Acheilognathinae and family Cyprinidae. The mitochondrial DNA sequence of P. chii is reported in this paper. The complete mitochondrial genome of P. chii is 16,575 bp in length, including 13 protein-coding genes (PCGs), 2 rRNA genes, 22 tRNA genes, and 1 displacement loop (D-loop). The genome sequence is consistent with those of most other carp. The majority of PCGs have AT- (Met) start codons and TA- end codons. The A + T contents of the genome, PCGs, transfer RNAs (tRNAs), and ribosomal RNAs (rRNAs) are 56.92%, 58.07%, 56.34%, and 54.21%, respectively. Phylogenetic analysis showed that P. chii is most closely related to Tanankia himantegus. These data will benefit relative ecological and phylogenetic studies.

Acheilognathinae↗

PubMed2025

Uncovering new lineages in the Sunda pangolin (Manis javanica) with museum mitogenomics.

Accurately identifying evolutionarily significant units (ESUs) is crucial for conservation planning, especially for species like pangolins threatened by overhunting and habitat loss. ESUs help categorize different pangolin populations, aiding in understanding their genetic diversity and distribution, which is vital for targeted conservation efforts. This research generated mitochondrial genomes from historical museum specimens of Sunda pangolins (Manis javanica) from underrepresented locations, uncovering a new evolutionary lineage from the Mentawai Islands that diverged from Indochina and west Sundaland populations around 760 000 years ago. This population thereby represents a divergent ESU with a small distribution, important for conservation planning. The novel sequences provide resources for forensic labs tracing the origin of confiscated scales and shed light into the potential distribution of the 'mysterious pangolin'. Additionally, this research confirmed the presence of the two major M. javanica lineages in Java and extended the known distribution of the eastern clade to Bali and East Kalimantan. Our findings potentially suggest a recent bottleneck and postglacial expansion of pangolins across Indochina and west Sundaland. Further investigation with genomic and morphological evidence, contact area sampling and type sequencing will be required to evaluate the taxonomic status of different M. javanica lineages and M. culionensis.

Genomics↗

PubMed2025

Ancient dog mitogenomes support the dual dispersal of dogs and agriculture into South America.

Archaeological and palaeogenomic data show that dogs were the only domestic animals introduced during the early peopling of the Americas. Hunter-gatherer groups spread quickly towards the south of the continent, but it is unclear when dogs reached Central and South America. To address this issue, we generated and analysed 70 complete mitochondrial genomes from archaeological and modern dogs ranging from Central Mexico to Central Chile and Argentina, revealing the dynamics of dog populations. Our results demonstrate that pre-contact Central and South American dogs are all assigned to a specific clade that diverged after dogs entered North America. Specifically, the divergence time between North, Central and South American dog clades is consistent with the spread of agriculture and the adoption of maize in South America between 7000 and 5000 years ago. An isolation-by-distance best characterizes how dogs expanded into South America. We identify the arrival of new lineages of dogs in post-contact South America, likely of European origin, and their legacy in modern village dogs. Interestingly, the pre-contact Mesoamerican maternal origin of the Chihuahua has persisted in some modern individuals.

Animals↗

PubMed2026

Characterization and comparative analysis of the complete mitochondrial genome sequence of Aucklandia lappa Decne.

BACKGROUND: Aucklandia lappa Decne, a precious medicinal herb in China, utilises the dried rhizome as its medicinal part, which riches in volatile oils, sesquiterpene compounds and other active constituents. Although the mitogenome of A. lappa has been assembled, related research remains in its preliminary stages, far from achieving comprehensive and in-depth understanding. RESULTS: In this paper, the complete mitogenome of A. lappa was assembled by employing a hybrid strategy that combined Illumina short-read and Nanopore long-read sequencing. The assembled mitogenome is 436,648 bp in size with a GC content of 45.06%. The mitogenome has only one chromosomal structure, It contains 54 genes, including 31 protein-coding genes(PCG), 19 tRNA genes, and 4 rRNA genes. A total of 32 high-frequency codons exhibiting significant AT-bias, 431 RNA editing sites, and 26 homologous fragments were transferred from the chloroplast to mitochondria genes (7,337 bp, 1.68%). Furthermore, we conducted a phylogenetic analysis involving in A. lappa and 27 other taxa to clarify its evolutionary and taxonomic status. These findings provide a foundation for further understanding the evolutionary relationships within Asteraceae plant. CONCLUSION: Through the assembly and comprehensive analysis of A. lappa mitogenome, This study has for the first time fully elucidated its mitogenomic structural characteristics.These results not only provide high-quality genetic resources for research on the Asteraceae mitogenome but also lay a solid foundation for in-depth exploration of the evolution and functional genomics of medicinal plants in the Asteraceae family.

Genome, Mitochondrial↗

PubMed2026

De Novo Assembly and Comparative Analysis of the Complete Mitochondrial Genome of Mesenchytraeus (Annelida, Enchytraeidae).

The Changbai Mountain range is one of the key glacial refugia in Northeast Asia. Mesenchytraeus exhibits high species diversity, strong endemism, and widespread cryptic species in this region, for which mitogenomes provide useful molecular markers for exploring cryptic species complexes. This makes Mesenchytraeus an ideal model for studying mitogenome evolution among closely related lineages; however, no mitogenome data have been reported for this genus to date. In this study, we performed de novo assembly, annotation, and comparative analysis of the mitogenomes of 13 Mesenchytraeus species (14 individuals) from Changbai Mountain. All mitogenomes are typical circular molecules containing 37 genes, but putative control regions are rearranged and consistently located between ATP6 and trnR. All species exhibit annelid-specific strand nucleotide biases, characterized by negative GC skew and near-zero AT skew. Codon usage analysis reveals that codon families with wobble U are significantly biased toward mtDNA codons, whereas those with wobble C or G are biased toward non-mtDNA codons, suggesting a conserved mitochondrial codon usage pattern in annelids. All tRNAs form typical cloverleaf secondary structures except trnS2, which lacks the D-stem and the dihydrouridine (DHU) arm in some species. The putative control regions commonly contain complex palindromic repeats, hairpins, and repetitive elements, and may harbor dual replication origins. Phylogenetic analyses support the monophyly of Mesenchytraeus and reveal significant molecular divergence among morphologically cryptic species. This study provides the first mitogenome dataset for Mesenchytraeus and offers new insights into the evolution and replication mechanisms of mitogenomes in Clitellata and broader Annelida.

Mesenchytraeus↗

PubMed2026

Exploring the Mitochondrial Genomes of Phoebe Species (Lauraceae): Structural Dynamics and Functional Conservation.

Plant mitochondrial genomes (mitogenomes) vary markedly in size and architecture despite generally slow rates of sequence evolution. Phoebe is an ecologically and economically valuable genus of Lauraceae, yet its mitogenome diversity remains poorly characterized. In this study, we newly sequenced, assembled, and annotated the mitogenomes of three nationally protected Class II wild plants (P. bournei, P. chekiangensis, P. zhennan) from China and compared their mitogenomic characteristics. The three assemblies were resolved into representative circular configurations ranging from 808 to 864 kb, with similar GC contents and conserved protein-coding capacity. Each mitogenome contained distinct 41 protein-coding genes, 27-28 transfer RNAs, and three ribosomal RNAs. Synteny analysis revealed extensive changes in homologous-block order and orientation despite substantial sequence homology among the three species. Abundant repeats occurred predominantly in noncoding regions, while plastid-derived fragments documented historical intracellular DNA transfer. The three species exhibited similar codon usage and predicted RNA-editing patterns, whereas low synonymous divergence limited inference from pairwise ratios. Phylogenetic analysis based on mitochondrial protein-coding genes recovered Phoebe as a well-supported monophyletic lineage. These results reveal substantial structural divergence accompanied by conserved nucleotide composition and coding capacity, providing valuable data for further understanding the evolutionary variation of plant mitogenomes of Phoebe and the Lauraceae.

Phoebe↗