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1.
PLoS One ; 17(5): e0263545, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35503755

RESUMO

BACKGROUND: Macadamia is a true dicotyledonous plant that thrives in a mild, humid, low wind environment. It is cultivated and traded internationally due to its high-quality nuts thus, has significant development prospects and scientific research value. However, information on the genetic resources of Macadamia spp. remains scanty. RESULTS: The mitochondria (mt) genomes of three economically important Macadamia species, Macadamia integrifolia, M. ternifolia and M. tetraphylla, were assembled through the Illumina sequencing platform. The results showed that each species has 71 genes, including 42 protein-coding genes, 26 tRNAs, and 3 rRNAs. Repeated sequence analysis, RNA editing site prediction, and analysis of genes migrating from chloroplast (cp) to mt were performed in the mt genomes of the three Macadamia species. Phylogenetic analysis based on the mt genome of the three Macadamia species and 35 other species was conducted to reveal the evolution and taxonomic status of Macadamia. Furthermore, the characteristics of the plant mt genome, including genome size and GC content, were studied through comparison with 36 other plant species. The final non-synonymous (Ka) and synonymous (Ks) substitution analysis showed that most of the protein-coding genes in the mt genome underwent negative selections, indicating their importance in the mt genome. CONCLUSION: The findings of this study provide a better understanding of the Macadamia genome and will inform future research on the genus.


Assuntos
Genoma de Cloroplastos , Genoma Mitocondrial , Tamanho do Genoma , Genoma Mitocondrial/genética , Genoma de Planta , Macadamia/genética , Filogenia
2.
Genome Biol Evol ; 14(4)2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35420669

RESUMO

Members of the Peronosporaceae (Oomycota, Chromista), which currently consists of 25 genera and approximately 1,000 recognized species, are responsible for disease on a wide range of plant hosts. Molecular phylogenetic analyses over the last two decades have improved our understanding of evolutionary relationships within Peronosporaceae. To date, 16 numbered and three named clades have been recognized; it is clear from these studies that the current taxonomy does not reflect evolutionary relationships. Whole organelle genome sequences are an increasingly important source of phylogenetic information, and in this study, we present comparative and phylogenetic analyses of mitogenome sequences from 15 of the 19 currently recognized clades of Peronosporaceae, including 44 newly assembled sequences. Our analyses suggest strong conservation of mitogenome size and gene content across Peronosporaceae but, as previous studies have suggested, limited conservation of synteny. Specifically, we identified 28 distinct syntenies amongst the 71 examined isolates. Moreover, 19 of the isolates contained inverted or direct repeats, suggesting repeated sequences may be more common than previously thought. In terms of phylogenetic relationships, our analyses of 34 concatenated mitochondrial gene sequences resulted in a topology that was broadly consistent with previous studies. However, unlike previous studies concatenated mitochondrial sequences provided strong support for higher-level relationships within the family.


Assuntos
Genoma Mitocondrial , Oomicetos , Evolução Molecular , Genes Mitocondriais , Oomicetos/genética , Filogenia , Sintenia
3.
Elife ; 112022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35404229

RESUMO

High frequencies of mutant mitochondrial DNA (mtDNA) in human cells lead to cellular defects that are associated with aging and disease. Yet much remains to be understood about the dynamics of the generation of mutant mtDNAs and their relative replicative fitness that informs their fate within cells and tissues. To address this, we utilize long-read single-molecule sequencing to track mutational trajectories of mtDNA in the model organism Saccharomyces cerevisiae. This model has numerous advantages over mammalian systems due to its much larger mtDNA and ease of artificially competing mutant and wild-type mtDNA copies in cells. We show a previously unseen pattern that constrains subsequent excision events in mtDNA fragmentation in yeast. We also provide evidence for the generation of rare and contentious non-periodic mtDNA structures that lead to persistent diversity within individual cells. Finally, we show that measurements of relative fitness of mtDNA fit a phenomenological model that highlights important biophysical parameters governing mtDNA fitness. Altogether, our study provides techniques and insights into the dynamics of large structural changes in genomes that we show are applicable to more complex organisms like humans.


Assuntos
Genoma Mitocondrial , Animais , DNA Mitocondrial/genética , Humanos , Mamíferos/genética , Mitocôndrias/genética , Dinâmica Mitocondrial , Saccharomyces cerevisiae/genética
4.
Sci Rep ; 12(1): 7028, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35487927

RESUMO

Uziflies (Family: Tachinidae) are dipteran endoparasites of sericigenous insects which cause major economic loss in the silk industry globally. Here, we are presenting the first full mitogenome of Blepharipa sp. (Acc: KY644698, 15,080 bp, A + T = 78.41%), a dipteran parasitoid of Muga silkworm (Antheraea assamensis) found in the Indian states of Assam and Meghalaya. This study has confirmed that Blepharipa sp. mitogenome gene content and arrangement is similar to other Tachinidae and Sarcophagidae flies of Oestroidea superfamily, typical of ancestral Diptera. Although, Calliphoridae and Oestridae flies have undergone tRNA translocation and insertion, forming unique intergenic spacers (IGS) and overlapping regions (OL) and a few of them (IGS, OL) have been conserved across Oestroidea flies. The Tachinidae mitogenomes exhibit more AT content and AT biased codons in their protein-coding genes (PCGs) than the Oestroidea counterpart. About 92.07% of all (3722) codons in PCGs of this new species have A/T in their 3rd codon position. The high proportion of AT and repeats in the control region (CR) affects sequence coverage, resulting in a short CR (Blepharipa sp.: 168 bp) and a smaller tachinid mitogenome. Our research unveils those genes with a high AT content had a reduced effective number of codons, leading to high codon usage bias. The neutrality test shows that natural selection has a stronger influence on codon usage bias than directed mutational pressure. This study also reveals that longer PCGs (e.g., nad5, cox1) have a higher codon usage bias than shorter PCGs (e.g., atp8, nad4l). The divergence rates increase nonlinearly as AT content at the 3rd codon position increases and higher rate of synonymous divergence than nonsynonymous divergence causes strong purifying selection. The phylogenetic analysis explains that Blepharipa sp. is well suited in the family of insectivorous tachinid maggots. It's possible that biased codon usage in the Tachinidae family reduces the effective number of codons, and purifying selection retains the core functions in their mitogenome, which could help with efficient metabolism in their endo-parasitic life style and survival strategy.


Assuntos
Dípteros , Genoma Mitocondrial , Animais , Códon/genética , Uso do Códon , Dípteros/genética , Genoma Mitocondrial/genética , Filogenia
5.
BMC Ecol Evol ; 22(1): 46, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35413835

RESUMO

BACKGROUND: Mitochondrial (mt) nucleotide sequence data has been by far the most common tool employed to investigate evolutionary relationships. While often considered to be more useful for shallow evolutionary scales, mt genomes have been increasingly shown also to contain valuable phylogenetic information about deep relationships. Further, mt genome organization provides another important source of phylogenetic information and gene reorganizations which are known to be relatively frequent within the insect order Hymenoptera. Here we used a dense taxon sampling comprising 148 mt genomes (132 newly generated) collectively representing members of most of the currently recognised subfamilies of the parasitoid wasp family Braconidae, which is one of the largest radiations of hymenopterans. We employed this data to investigate the evolutionary relationships within the family and to assess the phylogenetic informativeness of previously known and newly discovered mt gene rearrangements. RESULTS: Most subfamilial relationships and their composition obtained were similar to those recovered in a previous phylogenomic study, such as the restoration of Trachypetinae and the recognition of Apozyginae and Proteropinae as valid braconid subfamilies. We confirmed and detected phylogenetic signal in previously known as well as novel mt gene rearrangements, including mt rearrangements within the cyclostome subfamilies Doryctinae and Rogadinae. CONCLUSIONS: Our results showed that both the mt genome DNA sequence data and gene organization contain valuable phylogenetic signal to elucidate the evolution within Braconidae at different taxonomic levels. This study serves as a basis for further investigation of mt gene rearrangements at different taxonomic scales within the family.


Assuntos
Genoma Mitocondrial , Vespas , Animais , Rearranjo Gênico/genética , Genes Mitocondriais , Genoma Mitocondrial/genética , Filogenia , Vespas/genética
6.
Sci Rep ; 12(1): 5479, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35361853

RESUMO

Vertebrate mitochondrial genomes have been extensively studied for genetic and evolutionary purposes, these are normally believed to be extremely conserved, however, different cases of gene rearrangements have been reported. To verify the level of rearrangement and the mitogenome evolution, we performed a comparative genomic analysis of the 2831 vertebrate mitochondrial genomes representing 12 classes available in the NCBI database. Using a combination of bioinformatics methods, we determined there is a high number of errors in the annotation of mitochondrial genes, especially in tRNAs. We determined there is a large variation in the proportion of rearrangements per gene and per taxonomic class, with higher values observed in Actinopteri, Amphibia and Reptilia. We highlight that these are results for currently available vertebrate sequences, so an increase in sequence representativeness in some groups may alter the rearrangement rates, so in a few years it would be interesting to see if these rates are maintained or altered with the new mitogenome sequences. In addition, within each vertebrate class, different patterns in rearrangement proportion with distinct hotspots in the mitochondrial genome were found. We also determined that there are eleven convergence events in gene rearrangement, nine of which are new reports to the scientific community.


Assuntos
Evolução Molecular , Genoma Mitocondrial , Animais , Rearranjo Gênico/genética , Genoma Mitocondrial/genética , Genômica , Répteis/genética
7.
Sci Rep ; 12(1): 5642, 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35379869

RESUMO

Carangids are abundant and commercially important marine fish that contribute to a significant portion of the fisheries in many parts of the world. In the present study, we characterized the complete mitogenome of the Indian scad, Decapterus russelli and performed a comprehensive comparative mitogenomic analysis of the family Carangidae. The comparative mitogenomics provided valuable insights into the structure, variability, and features of the coding and non-coding regions that evolved across species over millions of years. The structural features of tRNAs revealed changes in the frequency of mismatched and wobble base pairs, which is reflected in the base composition of H and L strands. The highly conserved sequence motif of the mTERF binding site in carangids over the ~ 400 MYA of their divergence demonstrated the functional importance of these sites. The control region of carangids was characterized by the presence of discontinuous repeat units with a high rate of sequence divergence in the form of base substitutions, insertions, and deletions. The maintenance of secondary structures in the control region independent of the rapid evolution of primary structure suggested the effect of selective constraints on their maintenance. Maximum likelihood (ML) and Bayesian inference (BI) phylogeny revealed a similar topology consistent with previous taxonomic studies. The extant carangids diverged through the evolutionary events experienced during the Cretaceous, Paleogene, and Neogene periods.


Assuntos
Genoma Mitocondrial , Animais , Composição de Bases , Teorema de Bayes , Peixes/genética , Filogenia
8.
BMC Genomics ; 23(1): 253, 2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35366795

RESUMO

BACKGROUND: Classification of parasitic bopyrids has traditionally been based on morphological characteristics, but phylogenetic relationships have remained elusive due to limited information provided by morphological data and tendency for loss of morphological features as a result of parasitic lifestyle. Subfamily Argeiinae was separated from Bopyrinae based on morphological evidence, although the assignment of all genera has not been phylogenetically evaluated. Bopyroides hippolytes has been traditionally classified in Bopyrinae, but divergent morphological characters make this assignment questionable. To investigate the relationship of bopyrines, we sequenced the complete mitochondrial genome of B. hippolytes and four mitochondrial genes of two other Bopyrinae. RESULTS: The phylogenetic trees based on separate and combined cox1and 18S sequence data recovered Bopyridae as robustly monophyletic, but Bopyrinae as polyphyletic. Bopyroides hippolytes was a close sister to Argeia pugettensis, type species to Argeiinae. Mitochondrial phylogenomics also suggested that B. hippolytes was close to Argeiinae. We also found a novel gene order in B. hippolytes compared to other isopods. CONCLUSIONS: Bopyroides hippolytes should be excluded from the Bopyrinae and has a close affinity with Argeia pugettensis based on molecular and morphological data. The conserved syntenic blocks of mitochondrial gene order have distinctive characteristics at a subordinal level and may be helpful for understanding the higher taxonomic level relationships of Isopoda.


Assuntos
Genoma Mitocondrial , Isópodes , Animais , Ordem dos Genes , Genes Mitocondriais , Isópodes/genética , Filogenia
9.
BMC Genom Data ; 23(1): 28, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35418016

RESUMO

OBJECTIVES: Mirabilis jalapa L. and Bougainvillea spectabilis are two Mirabilis species known for their ornamental and pharmaceutical values. The organelle genomes are highly conserved with a rapid evolution rate making them suitable for evolutionary studies. Therefore, mitochondrial and chloroplast genomes of B. spectabilis and M. jalapa were sequenced to understand their evolutionary relationship with other angiosperms. DATA DESCRIPTION: Here, we report the complete mitochondrial genomes of B. spectabilis and M. jalapa (343,746 bp and 267,334 bp, respectively) and chloroplast genomes of B. spectabilis (154,520 bp) and M. jalapa (154,532 bp) obtained from Illumina NovaSeq. The mitochondrial genomes of B. spectabilis and M. jalapa consisted of 70 and 72 genes, respectively. Likewise, the chloroplast genomes of B. spectabilis and M. jalapa contained 131 and 132 genes, respectively. The generated genomic data will be useful for molecular characterization and evolutionary studies.


Assuntos
Genoma de Cloroplastos , Genoma Mitocondrial , Mirabilis , Nyctaginaceae , Genoma de Cloroplastos/genética , Genoma Mitocondrial/genética , Mirabilis/genética , Mitocôndrias/genética , Nyctaginaceae/genética
10.
Genome Biol Evol ; 14(5)2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35446419

RESUMO

Intracellular transfers of mitochondrial DNA continue to shape nuclear genomes. Chromosome 2 of the model plant Arabidopsis thaliana contains one of the largest known nuclear insertions of mitochondrial DNA (numts). Estimated at over 600 kb in size, this numt is larger than the entire Arabidopsis mitochondrial genome. The primary Arabidopsis nuclear reference genome contains less than half of the numt because of its structural complexity and repetitiveness. Recent data sets generated with improved long-read sequencing technologies (PacBio HiFi) provide an opportunity to finally determine the accurate sequence and structure of this numt. We performed a de novo assembly using sequencing data from recent initiatives to span the Arabidopsis centromeres, producing a gap-free sequence of the Chromosome 2 numt, which is 641 kb in length and has 99.933% nucleotide sequence identity with the actual mitochondrial genome. The numt assembly is consistent with the repetitive structure previously predicted from fiber-based fluorescent in situ hybridization. Nanopore sequencing data indicate that the numt has high levels of cytosine methylation, helping to explain its biased spectrum of nucleotide sequence divergence and supporting previous inferences that it is transcriptionally inactive. The original numt insertion appears to have involved multiple mitochondrial DNA copies with alternative structures that subsequently underwent an additional duplication event within the nuclear genome. This work provides insights into numt evolution, addresses one of the last unresolved regions of the Arabidopsis reference genome, and represents a resource for distinguishing between highly similar numt and mitochondrial sequences in studies of transcription, epigenetic modifications, and de novo mutations.


Assuntos
Arabidopsis , Genoma Mitocondrial , Arabidopsis/genética , Núcleo Celular/genética , DNA Mitocondrial/genética , Hibridização in Situ Fluorescente , Mitocôndrias/genética , Análise de Sequência de DNA
11.
BMC Genomics ; 23(1): 283, 2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35395774

RESUMO

BACKGROUND: The mitochondrial (mt) genomes of 15 species of sucking lice from seven families have been studied to date. These louse species have highly dynamic, fragmented mt genomes that differ in the number of minichromosomes, the gene content, and gene order in a minichromosome between families and even between species of the same genus. RESULTS: In the present study, we analyzed the publicly available data to understand mt genome fragmentation in seal lice (family Echinophthiriidae) and gorilla louse, Pthirus gorillae (family Pthiridae), in particular the role of minichromosome split and minichromosome merger in the evolution of fragmented mt genomes. We show that 1) at least three ancestral mt minichromosomes of sucking lice have split in the lineage leading to seal lice, 2) one minichromosome ancestral to primate lice has split in the lineage to the gorilla louse, and 3) two ancestral minichromosomes of seal lice have merged in the lineage to the northern fur seal louse. Minichromosome split occurred 15-16 times in total in the lineages leading to species in six families of sucking lice investigated. In contrast, minichromosome merger occurred only four times in the lineages leading to species in three families of sucking lice. Further, three ancestral mt minichromosomes of sucking lice have split multiple times independently in different lineages of sucking lice. Our analyses of mt karyotypes and gene sequences also indicate the possibility of a host switch of crabeater seal louse to Weddell seals. CONCLUSIONS: We conclude that: 1) minichromosome split contributes more than minichromosome merger in mt genome fragmentation of sucking lice, and 2) mt karyotype comparison helps understand the phylogenetic relationships between sucking louse species.


Assuntos
Anoplura , Genoma Mitocondrial , Animais , Anoplura/genética , Ordem dos Genes , Gorilla gorilla/genética , Filogenia
12.
BMC Genomics ; 23(1): 320, 2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35459089

RESUMO

BACKGROUND: Whole mitochondrial genomes are quickly becoming markers of choice for the exploration of within-species genealogical and among-species phylogenetic relationships. Most often, 'primer walking' or 'long PCR' strategies plus Sanger sequencing or low-pass whole genome sequencing using Illumina short reads are used for the assembling of mitochondrial chromosomes. In this study, we first confirmed that mitochondrial genomes can be sequenced from long reads using nanopore sequencing data exclusively. Next, we examined the accuracy of the long-reads assembled mitochondrial chromosomes when comparing them to a 'gold' standard reference mitochondrial chromosome assembled using Illumina short-reads sequencing. RESULTS: Using a specialized bioinformatics tool, we first produced a short-reads mitochondrial genome assembly for the silky shark C. falciformis with an average base coverage of 9.8x. The complete mitochondrial genome of C. falciformis was 16,705 bp in length and 934 bp shorter than a previously assembled genome (17,639 bp in length) that used bioinformatics tools not specialized for the assembly of mitochondrial chromosomes. Next, low-pass whole genome sequencing using a MinION ONT pocket-sized platform plus customized de-novo and reference-based workflows assembled and circularized a highly accurate mitochondrial genome in the silky shark Carcharhinus falciformis. Indels at the flanks of homopolymer regions explained most of the dissimilarities observed between the 'gold' standard reference mitochondrial genome (assembled using Illumina short reads) and each of the long-reads mitochondrial genome assemblies. Although not completely accurate, mitophylogenomics and barcoding analyses (using entire mitogenomes and the D-Loop/Control Region, respectively) suggest that long-reads assembled mitochondrial genomes are reliable for identifying a sequenced individual, such as C. falciformis, and separating the same individual from others belonging to closely related congeneric species. CONCLUSIONS: This study confirms that mitochondrial genomes can be sequenced from long-reads nanopore sequencing data exclusively. With further development, nanopore technology can be used to quickly test in situ mislabeling in the shark fin fishing industry and thus, improve surveillance protocols, law enforcement, and the regulation of this fishery. This study will also assist with the transferring of high-throughput sequencing technology to middle- and low-income countries so that international scientists can explore population genomics in sharks using inclusive research strategies. Lastly, we recommend assembling mitochondrial genomes using specialized assemblers instead of other assemblers developed for bacterial and/or nuclear genomes.


Assuntos
Genoma Mitocondrial , Sequenciamento por Nanoporos , Nanoporos , Tubarões , Animais , Benchmarking , Genoma Mitocondrial/genética , Ouro , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Filogenia , Análise de Sequência de DNA/métodos , Tubarões/genética
13.
Genes (Basel) ; 13(4)2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-35456466

RESUMO

Groupers are commercial, mainly reef-associated fishes, classified in the family Epinephelidae (Perciformes). This study first sequenced the complete mitogenomes of Cephalopholis leopardus, Cephalopholis spiloparaea, Epinephelus amblycephalus, and Epinephelus hexagonatus. The lengths of the four Epinephelidae mitogenomes ranged from 16,585 base pair (bp) to 16,872 bp with the typical gene order. All tRNA genes had a typical cloverleaf structure, except the tRNA-Ser (AGY) gene which was lacking the entire dihydrouridine arm. The ratio of nonsynonymous substitution (Ka) and synonymous substitution (Ks) indicated that four groupers were suffering a purifying selection. Phylogenetic relationships were reconstructed by Bayesian inference (BI) and maximum likelihood (ML) methods based on all mitogenomic data of 41 groupers and 2 outgroups. The identical topologies result with high support values showed that Cephalopholis and Epinephelus are not monophyletic genera. Anyperodon and Cromileptes clustered to Epinephelus. Aethaloperca rogaa and Cephalopholis argus assembled a clad. Cephalopholis leopardus, C. spiloparaea, and Cephalopholis miniata are also in a clade. Epinephelushexagonatus is close to Epinephelus tauvina and Epinephelus merra, and E. amblycephalus is a sister group with Epinephelus stictus. More mitogenomic data from Epinephelidae species are essential to understand its taxonomic status with the family Serranidae.


Assuntos
Bass , Genoma Mitocondrial , Perciformes , Animais , Bass/genética , Teorema de Bayes , Genoma Mitocondrial/genética , Perciformes/genética , Filogenia , RNA de Transferência/genética
14.
Parasit Vectors ; 15(1): 149, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35477556

RESUMO

BACKGROUND: Diplozoidae are monogenean (Monogenea: Polyopisthocotylea) fish parasites characterised by a unique life history: two larvae permanently fuse into an X-shaped "Siamese" organism. Taxonomy and phylogeny of Diplozoidae and Polyopisthocotylea remain unresolved due to the unavailability of molecular markers with sufficiently high resolution. Mitogenomes may be a suitable candidate, but there are currently only 12 available for the Polyopisthocotylea (three for Diplozoidae). The only available study of diplozoid mitogenomes found unique base composition patterns and elevated evolution rates in comparison with other Monogenean mitogenomes. METHODS: To further explore their evolution and generate molecular data for evolutionary studies, we sequenced the complete mitogenomes of two Diplozoidae species, Paradiplozoon homoion and Paradiplozoon yarkandense, and conducted a number of comparative mitogenomic analyses with other polyopisthocotyleans. RESULTS: We found further evidence that mitogenomes of Diplozoidae evolve at a unique, elevated rate, which was reflected in their exceptionally long branches, large sizes, unique base composition, skews, and very low gene sequence similarity levels between the two newly sequenced species. They also exhibited remarkably large overlaps between some genes. Phylogenetic analysis of Polyopisthocotylea resolved all major taxa as monophyletic, and Mazocraeidea was split into two major clades: (Diplozoidae) + (all four remaining families: Diclidophoridae, Chauhaneidae, Mazocraeidae and Microcotylidae). It also provided further confirmation that the genus Paradiplozoon is paraphyletic and requires a taxonomic revision, so the two species may have to be renamed Indodiplozoon homoion and Diplozoon yarkandense comb. nov. CONCLUSIONS: Although our findings indicate that mitogenomes may be a promising tool for resolving the phylogeny of Polyopisthocotylea, elevated evolutionary rates of Diplozoidae may cause phylogenetic artefacts, so future studies should pay caution to this problem. Furthermore, as the reason for their elevated evolution remains unknown, Diplozoidae are a remarkably interesting lineage for other types of evolutionary mitogenomic studies.


Assuntos
Genoma Mitocondrial , Trematódeos , Animais , Composição de Bases , Peixes/parasitologia , Humanos , Filogenia , Trematódeos/genética
15.
Sci Rep ; 12(1): 5582, 2022 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-35379858

RESUMO

Maternal diversity based on a sub-region of mitochondrial genome or variants were commonly used to understand past demographic events in livestock. Additionally, there is growing evidence of direct association of mitochondrial genetic variants with a range of phenotypes. Therefore, this study used complete bovine mitogenomes from a large sequence database to explore the full spectrum of maternal diversity. Mitogenome diversity was evaluated among 1883 animals representing 156 globally important cattle breeds. Overall, the mitogenomes were diverse: presenting 11 major haplogroups, expanding to 1309 unique haplotypes, with nucleotide diversity 0.011 and haplotype diversity 0.999. A small proportion of African taurine (3.5%) and indicine (1.3%) haplogroups were found among the European taurine breeds and composites. The haplogrouping was largely consistent with the population structure derived from alternate clustering methods (e.g. PCA and hierarchical clustering). Further, we present evidence confirming a new indicine subgroup (I1a, 64 animals) mainly consisting of breeds originating from China and characterised by two private mutations within the I1 haplogroup. The total genetic variation was attributed mainly to within-breed variance (96.9%). The accuracy of the imputation of missing genotypes was high (99.8%) except for the relatively rare heteroplasmic genotypes, suggesting the potential for trait association studies within a breed.


Assuntos
Genoma Mitocondrial , Animais , Bovinos/genética , Variação Genética , Genótipo , Haplótipos/genética , Taurina
16.
BMC Genomics ; 23(1): 276, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35392795

RESUMO

BACKGROUND: Immortalized cell lines are widely used model systems whose genomes are often highly rearranged and polyploid. However, their genome structure is seldom deciphered and is thus not accounted for during analyses. We therefore used linked short- and long-read sequencing to perform haplotype-level reconstruction of the genome of a Drosophila melanogaster cell line (S2-DRSC) with a complex genome structure. RESULTS: Using a custom implementation (that is designed to use ultra-long reads in complex genomes with nested rearrangements) to call structural variants (SVs), we found that the most common SV was repetitive sequence insertion or deletion (> 80% of SVs), with Gypsy retrotransposon insertions dominating. The second most common SV was local sequence duplication. SNPs and other SVs were rarer, but several large chromosomal translocations and mitochondrial genome insertions were observed. Haplotypes were highly similar at the nucleotide level but structurally very different. Insertion SVs existed at various haplotype frequencies and were unlinked on chromosomes, demonstrating that haplotypes have different structures and suggesting the existence of a mechanism that allows SVs to propagate across haplotypes. Finally, using public short-read data, we found that transposable element insertions and local duplications are common in other D. melanogaster cell lines. CONCLUSIONS: The S2-DRSC cell line evolved through retrotransposon activity and vast local sequence duplications, that we hypothesize were the products of DNA re-replication events. Additionally, mutations can propagate across haplotypes (possibly explained by mitotic recombination), which enables fine-tuning of mutational impact and prevents accumulation of deleterious events, an inherent problem of clonal reproduction. We conclude that traditional linear homozygous genome representation conceals the complexity when dealing with rearranged and heterozygous clonal cells.


Assuntos
Drosophila melanogaster , Genoma Mitocondrial , Animais , Linhagem Celular , Drosophila/genética , Drosophila melanogaster/genética , Haplótipos , Reprodução , Retroelementos/genética , Análise de Sequência de DNA
17.
Sci Rep ; 12(1): 5829, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35388060

RESUMO

The evolution of Australia's distinctive marsupial fauna has long been linked to the onset of continent-wide aridity. However, how this profound climate change event affected the diversification of extant lineages is still hotly debated. Here, we assemble a DNA sequence dataset of Macropodoidea-the clade comprising kangaroos and their relatives-that incorporates a complete mitogenome for the Desert 'rat-kangaroo', Caloprymnus campestris. This enigmatic species went extinct nearly 90 years ago and is known from a handful of museum specimens. Caloprymnus is significant because it was the only macropodoid restricted to extreme desert environments, and therefore calibrates the group's specialisation for increasingly arid conditions. Our robustly supported phylogenies nest Caloprymnus amongst the bettongs Aepyprymnus and Bettongia. Dated ancestral range estimations further reveal that the Caloprymnus-Bettongia lineage originated in nascent xeric settings during the middle to late Miocene, ~ 12 million years ago (Ma), but subsequently radiated into fragmenting mesic habitats after the Pliocene to mid-Pleistocene. This timeframe parallels the ancestral divergences of kangaroos in woodlands and forests, but predates their adaptive dispersal into proliferating dry shrublands and grasslands from the late Miocene to mid-Pleistocene, after ~ 7 Ma. We thus demonstrate that protracted changes in both climate and vegetation likely staged the emergence of modern arid zone macropodoids.


Assuntos
Genoma Mitocondrial , Macropodidae , Adaptação Fisiológica , Animais , Clima Desértico , Filogenia , Potoroidae , Ratos
18.
Sci Rep ; 12(1): 6827, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35473946

RESUMO

Estimates of mutation rates for various regions of the human mitochondrial genome (mtGenome) vary widely, depending on whether they are inferred using a phylogenetic approach or obtained directly from pedigrees. Traditionally, only the control region, or small portions of the coding region have been targeted for analysis due to the cost and effort required to produce whole mtGenome Sanger profiles. Here, we report one of the first pedigree derived mutation rates for the entire human mtGenome. The entire mtGenome from 225 individuals originating from Norfolk Island was analysed to estimate the pedigree derived mutation rate and compared against published mutation rates. These individuals were from 45 maternal lineages spanning 345 generational events. Mutation rates for various portions of the mtGenome were calculated. Nine mutations (including two transitions and seven cases of heteroplasmy) were observed, resulting in a rate of 0.058 mutations/site/million years (95% CI 0.031-0.108). These mutation rates are approximately 16 times higher than estimates derived from phylogenetic analysis with heteroplasmy detected in 13 samples (n = 225, 5.8% individuals). Providing one of the first pedigree derived estimates for the entire mtGenome, this study provides a better understanding of human mtGenome evolution and has relevance to many research fields, including medicine, anthropology and forensics.


Assuntos
Genoma Mitocondrial , DNA Mitocondrial/genética , Genoma Mitocondrial/genética , Humanos , Taxa de Mutação , Linhagem , Filogenia
19.
Zootaxa ; 5087(1): 129-153, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35390922

RESUMO

Seven new species and the female sex of Rhaphidophora xishuang Gorochov, 2012 of the rhaphidophorines are described from China. The images illustrating the morphology of the two known species are provided. Meanwhile, the complete mitogenome of Rhaphidophora quadrispina was assembled. The mitogenome was 15892 bp in length and contained the typical gene arrangement. All examined specimens are deposited in the Guangxi Normal University.


Assuntos
Araceae , Genoma Mitocondrial , Ortópteros , Distribuição Animal , Estruturas Animais , Animais , Araceae/genética , Tamanho Corporal , China , Feminino , Humanos , Tamanho do Órgão , Ortópteros/anatomia & histologia , Ortópteros/genética
20.
Zootaxa ; 5100(3): 349-360, 2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35391071

RESUMO

This paper is the fourth study of the subfamily Anostostomatinae from China and reports one newly recorded species, Anabropsis (Apteranabropsis) tonkinensis Rehn, 1906. Also, we reported the mitochondrial genome and inferred the phylogenic relationship among the genus Anabropsis based on two specimens. Two complete mitogenomes were 16059 and 16052 bp in size and consisted of 37 genes and a control region. The overall base composition exhibited a clear AT bias. Most protein-coding genes started with the codon ATN and ended with typical stop codons TAA. The phylogenetic analyses based on mitogenomes and several morphological characteristics provided meaningful genetic information for Anabropsis and validated the phylogenetic relationships among the subgenera.


Assuntos
Genoma Mitocondrial , Ortópteros , Animais , Composição de Bases , Filogenia
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