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1.
Gene ; 726: 144154, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31589962

RESUMO

In this work the complete chloroplast DNAs of Allium paradoxum and Allium ursinum, two edible species of Allium subg. Amerallium (the first lineage), were sequenced, assembled, annotated, and compared with complete Allium plastomes of the second and third evolutionary lines from GenBank database. The A. ursinum plastome contains 90 predicted genes (81 unique) including 5 pseudogenes, while A. paradoxum has 88 predicted genes (79 unique) including 19 pseudogenes. The comparative analysis has revealed that the A. paradoxum plastome differs markedly from those of other species. Due to many deletions, the A. paradoxum plastome is the shortest of known for Allium species, being only 145,819 bp long. The most prominent distinctions are (1) a 4825 bp long local inversion that spans from the ndhE to the rpl32 gene in the small single copy region and (2) pseudogenization, or the loss of all NADH-genes. In contrast, the plastome of A. ursinum - a species from the first evolutionary line (as well as A. paradoxum) - resembles the Allium species of the second and third evolutionary lines, showing no large rearrangements or discrepancies in gene content. It is unclear yet whether only A. paradoxum was affected by some evolutionary events or its close relatives from both sect. Briseis and other sections of Amerallium were altered as well. We speculate the sunlight-intolerant, shade-loving nature of A. paradoxum and the impairment of the ndh genes in its plastome could be interrelated phenomena.


Assuntos
Allium/genética , Rearranjo Gênico/genética , Genes de Plantas/genética , Cebolas/genética , DNA de Cloroplastos/genética , DNA de Plantas/genética , Evolução Molecular , Genoma de Cloroplastos/genética , Genoma de Planta/genética , Filogenia , Folhas de Planta/genética , Pseudogenes/genética , Análise de Sequência de DNA/métodos
2.
Biomed Res Int ; 2019: 7265030, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31531364

RESUMO

The papilionoid legume genus Ormosia comprises approximately 130 species, which are distributed mostly in the Neotropics, with some species in eastern Asia and northeastern Australia. The taxonomy and evolutionary history remain unclear due to the lack of a robust species-level phylogeny. Chloroplast genomes can provide important information for phylogenetic and population genetic studies. In this study, we determined the complete chloroplast genome sequences of five Ormosia species by Illumina sequencing. The Ormosia chloroplast genomes displayed the typical quadripartite structure of angiosperms, which consisted of a pair of inverted regions separated by a large single-copy region and a small single-copy region. The location and distribution of repeat sequences and microsatellites were determined. Comparative analyses highlighted a wide spectrum of variation, with trnK-rbcL, atpE-trnS-rps4, trnC-petN, trnS-psbZ-trnG, trnP-psaJ-rpl33, and clpP intron being the most variable regions. Phylogenetic analysis revealed that Ormosia is in the Papilionoideae clade and is sister to the Lupinus clade. Overall, this study, which provides Ormosia chloroplast genomic resources and a comparative analysis of Ormosia chloroplast genomes, will be beneficial for the evolutionary study and phylogenetic reconstruction of the genus Ormosia and molecular barcoding in population genetics and will provide insight into the chloroplast genome evolution of legumes.


Assuntos
Cloroplastos/genética , Fabaceae/genética , Genoma de Cloroplastos/genética , Mutação/genética , Austrália , DNA de Cloroplastos/genética , Evolução Molecular , Extremo Oriente , Genética Populacional/métodos , Genômica/métodos , Repetições de Microssatélites/genética , Filogenia , Análise de Sequência de DNA/métodos
3.
Genes Genet Syst ; 94(4): 151-158, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31495805

RESUMO

Arabidopsis thaliana, one of the most important model plants, has played an essential role in every biological field including evolutionary biology. Recent population genomic studies have gradually clarified the origin and evolution of this species. Nevertheless, incongruent patterns among gene trees based on cytogenetic data have highlighted the importance of understanding the life history evolution and landscape biogeography of extant A. thaliana populations. Here, we focus on the maternally inherited chloroplast genome in A. thaliana and carry out phylogeographic analyses and coalescent time estimations. The maternal lineage of A. thaliana originated in the European to West and Central Asian regions in the Early Pleistocene. Relicts, the ancient lineages suggested by population genomic data, are not ancestral maternal lineages, but are derived from the European population. Part of the European population then dispersed eastward and spread to the Indian region, and finally extended to the Yangtze River region. The branching patterns and evolutionary time scales of the maternal genealogy are significantly different from those estimated from analyses of autosomal genes, and these cannot be explained by incomplete lineage sorting of the ancestral polymorphisms during the coalescent process due to large differences in the evolutionary time scale involved.


Assuntos
Arabidopsis/genética , Cloroplastos/genética , DNA de Cloroplastos/genética , Evolução Molecular , Variação Genética/genética , Genética Populacional , Herança Materna/genética , Filogeografia , Análise de Sequência de DNA
4.
BMC Plant Biol ; 19(1): 361, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31419941

RESUMO

BACKGROUND: The transfer of chloroplast DNA into nuclear genome is a common process in plants. These transfers form nuclear integrants of plastid DNAs (NUPTs), which are thought to be driving forces in genome evolution, including sex chromosome evolution. In this study, NUPTs in the genome of a dioecious plant Asparagus officinalis L. were systematically analyzed, in order to investigate the characteristics of NUPTs in the nuclear genome and the relationship between NUPTs and sex chromosome evolution in this species. RESULTS: A total of 3155 NUPT insertions were detected, and they represented approximated 0.06% of the nuclear genome. About 45% of the NUPTs were organized in clusters. These clusters were derived from various evolutionary events. The Y chromosome contained the highest number and largest proportion of NUPTs, suggesting more accumulation of NUPTs on sex chromosomes. NUPTs were distributed widely in all of the chromosomes, and some regions preferred these insertions. The highest density of NUPTs was found in a 47 kb region in the Y chromosome; more than 75% of this region was occupied by NUPTs. Further cytogenetic and sequence alignment analysis revealed that this region was likely the centromeric region of the sex chromosomes. On the other hand, the male-specific region of the Y chromosome (MSY) and the adjacent regions did not have NUPT insertions. CONCLUSIONS: These results indicated that NUPTs were involved in shaping the genome of A. officinalis through complicated process. NUPTs may play important roles in the centromere shaping of the sex chromosomes of A. officinalis, but were not implicated in MSY formation.


Assuntos
Asparagus (Planta)/genética , Núcleo Celular/genética , Cromossomos de Plantas/genética , DNA de Cloroplastos/genética , Genoma de Planta/genética , Evolução Biológica , Evolução Molecular
5.
PLoS One ; 14(7): e0216966, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31291259

RESUMO

Larix populations at the tundra-taiga ecotone in northern Siberia are highly under-represented in population genetic studies, possibly due to the remoteness of these regions that can only be accessed at extraordinary expense. The genetic signatures of populations in these boundary regions are therefore largely unknown. We aim to generate organelle reference genomes for the detection of single nucleotide polymorphisms (SNPs) that can be used for paleogenetic studies. We present 19 complete chloroplast genomes and mitochondrial genomic sequences of larches from the southern lowlands of the Taymyr Peninsula (northernmost range of Larix gmelinii (Rupr.) Kuzen.), the lower Omoloy River, and the lower Kolyma River (both in the range of Larix cajanderi Mayr). The genomic data reveal 84 chloroplast SNPs and 213 putatively mitochondrial SNPs. Parsimony-based chloroplast haplotype networks show no spatial structure of individuals from different geographic origins, while the mitochondrial haplotype network shows at least a slight spatial structure with haplotypes from the Omoloy and Kolyma populations being more closely related to each other than to most of the haplotypes from the Taymyr populations. Whole genome alignments with publicly available complete chloroplast genomes of different Larix species show that among official plant barcodes only the rcbL gene contains sufficient polymorphisms, but has to be sequenced completely to distinguish the different provenances. We provide 8 novel mitochondrial SNPs that are putatively diagnostic for the separation of L. gmelinii and L. cajanderi, while 4 chloroplast SNPs have the potential to distinguish the L. gmelinii/L. cajanderi group from other Larix species. Our organelle references can be used for a targeted primer and probe design allowing the generation of short amplicons. This is particularly important with regard to future investigations of, for example, the biogeographic history of Larix by screening ancient sedimentary DNA of Larix.


Assuntos
Larix/genética , Mapeamento Cromossômico , DNA Antigo , DNA de Cloroplastos/genética , DNA Mitocondrial/genética , DNA de Plantas/genética , Variação Genética , Genética Populacional , Genoma de Cloroplastos , Genoma Mitocondrial , Genoma de Planta , Haplótipos , História Antiga , Larix/classificação , Polimorfismo de Nucleotídeo Único , Sibéria , Taiga , Tundra
6.
PLoS One ; 14(7): e0219070, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31329604

RESUMO

Knowing what animals eat is fundamental to our ability to understand and manage biodiversity and ecosystems, but researchers often must rely on indirect methods to infer trophic position and food intake. Using an approach that combines evidence from stable isotope analysis and DNA metabarcoding, we assessed the diet and trophic position of Anthene usamba butterflies, for which there are no known direct observations of larval feeding. An earlier study that analyzed adults rather than caterpillars of A. usamba inferred that this butterfly was aphytophagous, but we found that the larval guts of A. usamba and two known herbivorous lycaenid species contain chloroplast 16S sequences. Moreover, chloroplast barcoding revealed high sequence similarity between chloroplasts found in A. usamba guts and the chloroplasts of the Vachellia drepanolobium trees on which the caterpillars live. Stable isotope analysis provided further evidence that A. usamba caterpillars feed on V. drepanolobium, and the possibilities of strict herbivory versus limited omnivory in this species are discussed. These results highlight the importance of combining multiple approaches and considering ontogeny when using stable isotopes to infer trophic ecology where direct observations are difficult or impossible.


Assuntos
Borboletas/fisiologia , Dieta , Ecossistema , Animais , Formigas/fisiologia , Isótopos de Carbono , Código de Barras de DNA Taxonômico , DNA de Cloroplastos/genética , DNA de Cloroplastos/isolamento & purificação , Fabaceae/química , Fabaceae/genética , Microbioma Gastrointestinal/genética , Herbivoria/genética , Larva/fisiologia , Isótopos de Nitrogênio , Simbiose
7.
PLoS One ; 14(6): e0218817, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31233551

RESUMO

Alpinia oxyphylla Miq. (A. oxyphylla) is an important edible and traditional herbal medicine. In this study, the complete chloroplast genome of A. oxyphylla was sequenced, analysed, and compared to five species in the Zingiberaceae family. The size of the A. oxyphylla chloroplast genome was 161351 bp, which consisted of a large single-copy (LSC, 87248 bp) and small single-copy (SSC, 16175 bp) region separated by a pair of inverted repeats (IRa and IRb, 28964 bp each). The genome encoded 132 unique genes, including 87 protein-coding genes, 37 tRNAs and four rRNAs. The GC content of the genome was 36.17%. A total of 53 simple sequence repeats (SSRs) and 80 long repeats were identified in the A. oxyphylla chloroplast genome. The chloroplast genome of A. oxyphylla shared the highest sequence similarity of >90% with the chloroplast genome of A. zerumbet, and six chloroplast genomes in the Zingiberaceae family were compared by using CGView Comparison Tool (CCT). According to the phylogenetic tree, the Zingiberaceae family is divided into two categories, which coincide with the classification of the characteristics of sun-like and shade-like in plants. Our results reveal the phototrophic component of NADH-dehydrogenase (ndhB and ndhC), photosystem II (psbZ) and ATP synthase (atpE, atpF) exhibit adaptive evolution under different environments, and the strength of light is an important trigger for the adaptations at the chloroplast level.


Assuntos
Alpinia/genética , Genoma de Cloroplastos , Genoma de Planta , Plantas Medicinais/genética , Zingiberaceae/genética , Aclimatação/genética , Composição de Bases , China , Mapeamento Cromossômico , DNA de Cloroplastos/genética , DNA de Plantas/genética , Medicamentos de Ervas Chinesas , Evolução Molecular , Repetições de Microssatélites , Filogenia , Zingiberaceae/classificação
8.
PLoS One ; 14(5): e0216645, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31071159

RESUMO

Camellia is an economically, ecologically and phylogenetically valuable genus in the family Theaceae. The frequent interspecific hybridization and polyploidization makes this genus phylogenetically and taxonomically under controversial and require detailed investigation. Chloroplast (cp) genome sequences have been used for cpDNA marker development and genetic diversity evaluation. Our research newly sequenced the chloroplast genome of Camellia japonica using Illumina HiSeq X Ten platform, and retrieved five other chloroplast genomes of Camellia previously published for comparative analyses, thereby shedding lights on a deeper understanding of the applicability of chloroplast information. The chloroplast genome sizes ranged in length from 156,607 to 157,166 bp, and their gene structure resembled those of other higher plants. There were four categories of SSRs detected in six Camellia cpDNA sequences, with the lengths ranging from 10 to 17bp. The Camellia species exhibited different evolutionary routes that lhbA and orf188, followed by orf42 and psbZ, were readily lost during evolution. Obvious codon preferences were also shown in almost all protein-coding cpDNA and amino acid sequences. Selection pressure analysis revealed the influence of different environmental pressures on different Camellia chloroplast genomes during long-term evolution. All Camellia species, except C. crapnelliana, presented the identical rate of amplification in the IR region. The datasets obtained from the chloroplast genomes are highly supportive in inferring the phylogenetic relationships of the Camellia taxa, indicating that chloroplast genome can be used for classifying interspecific relationships in this genus.


Assuntos
Camellia/classificação , Camellia/genética , Genoma de Cloroplastos , Mapeamento Cromossômico , Códon/genética , Código de Barras de DNA Taxonômico , DNA de Cloroplastos/genética , Evolução Molecular , Marcadores Genéticos , Genoma de Planta , Repetições de Microssatélites , Filogenia , Seleção Genética
9.
J Genet ; 982019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30945682

RESUMO

Dipentodon is a monotypic genus of Dipentodontaceae and the only species, Dipentodon sinicus, is scattered in southwest China as well as adjacent Myanmar, northeast India and northern Vietnam. This species was evaluated as vulnerable in 'China Species Red List'. Here, we assembled and characterized the complete chloroplast (cp) genome of D. sinicus using Illumina sequencing data for the first time. The complete cp genome was 158,795 bp in length, consisting of a pair of inverted repeats of 26,587 bp, a large single-copy region of 87,233 bp and a small single-copy region of 18,388 bp. The genome encoded 113 unique genes, including 79 protein-coding genes, 30 tRNA genes and four rRNA genes. Phylogenetic analysis based on 16 complete cp genome sequences indicated that D. sinicus is a member of Huerteales, consistent with its position in the latest classification of flowering plants (AGP IV).


Assuntos
Proteínas de Cloroplastos/genética , Cloroplastos/genética , DNA de Cloroplastos/genética , Genoma de Cloroplastos , Magnoliopsida/genética , Magnoliopsida/classificação , Sequenciamento Completo do Genoma
10.
Biomed Res Int ; 2019: 5046958, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31016191

RESUMO

Sorghum comprises 31 species that exhibit considerable morphological and ecological diversity. The phylogenetic relationships among Sorghum species still remain unresolved due to lower information on the traditional DNA markers, which provides a limited resolution for identifying Sorghum species. In this study, we sequenced the complete chloroplast genomes of Sorghum sudanense and S. propinquum and analyzed the published chloroplast genomes of S. bicolor and S. timorense to retrieve valuable chloroplast molecular resources for Sorghum. The chloroplast genomes ranged in length from 140,629 to 140,755 bp, and their gene contents, gene orders, and GC contents were similar to those for other Poaceae species but were slightly different in the number of SSRs. Comparative analyses among the four chloroplast genomes revealed 651 variable sites, 137 indels, and nine small inversions. Four highly divergent DNA regions (rps16-trnQ, trnG-trnM, rbcL-psaI, and rps15-ndhF), which were suitable for phylogenetic and species identification, were detected in the Sorghum chloroplast genomes. A phylogenetic analysis strongly supported that Sorghum is a monophyletic group in the tribe Andropogoneae. Overall, the genomic resources in this study could provide potential molecular markers for phylogeny and species identification in Sorghum.


Assuntos
Cloroplastos/genética , Genoma de Cloroplastos/genética , Sorghum/genética , Composição de Bases/genética , DNA de Cloroplastos/genética , Ordem dos Genes/genética , Marcadores Genéticos/genética , Genômica/métodos , Filogenia , Poaceae/genética , Análise de Sequência de DNA/métodos
11.
Int J Mol Sci ; 20(7)2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30974837

RESUMO

Trentepohliales is an aerial order of Chlorophyta with approximately 80 species distributed mainly in tropical and subtropical regions. The taxonomy of this genus is quite difficult and presents a challenge for many phycologists. Although plentiful molecular data is available, most of the sequences are not identified at the species level. In the present study, we described a new specimen with detailed morphological data and identified it as Trentepohlia odorata. A phylogenetic analysis showed T. odorata as a novel lineage in Trentepohliales. T. odorata has the closest relationship with T. annulata, which is expected since sporangia of both species are without stalk cell and with dorsal pore. Species with such morphological characteristics may represent deep lineages in Trentepohliales. Although an increasing number of chloroplast genomes of Ulvophyceae have been reported in recent years, the whole plastome of Trentepohliales has not yet been reported. Thus, the chloroplast genome of Trentepohlia odorata was reported in the present study. The whole plastome was 399,372 bp in length, with 63 predicted protein-coding genes, 31 tRNAs, and 3 rRNAs. Additionally, we annotated 95 free-standing open reading frames, of which seven were annotated with plastid origins, 16 with eukaryotic genome origins, and 33 with bacterial genome origins. Four rpo genes (rpoA, rpoB, rpoC1, and rpoC2) were annotated within ORF clusters. These four genes were fragmented into several (partial) ORFs by in-frame stop codons. Additionally, we detected a frame shift mutation in the rpoB gene. The phylogenetic analysis supported that Trentepohliales clustered with Dasycladales and nested into the BDT clade (Bryopsidales, Dasycladales and Trentepohliales). Our results present the first whole chloroplast genome of a species of Trentepohliales and provided new data for understanding the evolution of the chloroplast genome in Ulvophyceae.


Assuntos
Clorófitas , DNA de Cloroplastos/genética , Evolução Molecular , Genoma de Cloroplastos , Filogenia , Clorófitas/classificação , Clorófitas/genética , Ordem dos Genes , Fases de Leitura Aberta
12.
Planta ; 250(1): 95-104, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30923906

RESUMO

MAIN CONCLUSION: A method for extraction of wood DNA and a strategy for designing high-resolution barcodes for wood were developed. Ycf1b was the prioritized barcode to resolve the Pterocarpus wood species studied. DNA barcoding, an effective tool for wood species identification, mainly focuses on universal barcodes and often lacks high resolution to differentiate species, especially for closely related taxa within the same genus. Therefore, more highly informative DNA barcodes need to be identified. This study is the first to report a strategy for developing specific DNA barcodes of wood tissues. The complete chloroplast genomes of leaf samples of three Pterocarpus species, i.e., P. indicus, P. santalinus, and P. tinctorius, were sequenced, and thereafter, the most variable DNA regions were identified on the scale of the complete chloroplast genomes. Finally, wood DNA was extracted from 30 wood specimens of the three Pterocarpus species, and DNA recovery rates of the selected regions were tested for applicability to verification on the wood specimens studied. The seven regions with the most variation (rpl32-ccsA, rpl20-clpP, trnC-rpoB, ycf1b, accD-ycf4, ycf1a, and psbK-accD) were identified from the chloroplast genome by quantifying nucleotide diversity (Pi > 0.02), which was remarkably higher than that of the plant universal barcodes (rbcL, matK, and trnH-psbA) and the previously reported barcodes (ndhF-rpl32 and trnL-F) used for phylogenetic analysis in Pterocarpus. After comprehensive evaluation of species discrimination ability and applicability, the ycf1b region performed well in terms of the recovery success rate (76.7%) and species identification (100%) for wood specimens of the three Pterocarpus species, and was identified as the preferred high-resolution chloroplast barcode for selected Pterocarpus species. It will offer technical support for curbing illegal timber harvesting activities and for conserving endangered and valuable wood species.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Genoma de Cloroplastos/genética , Genoma de Planta/genética , Pterocarpus/classificação , DNA de Cloroplastos/genética , DNA de Plantas/genética , Filogenia , Pterocarpus/genética , Especificidade da Espécie , Madeira/genética
13.
Am J Bot ; 106(3): 415-437, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30882906

RESUMO

PREMISE OF THE STUDY: Polyploidy has been long recognized as an important force in plant evolution. Previous studies had suggested widespread occurrence of polyploidy and the allopolyploid origin of several species in the diverse neotropical genus Lachemilla (Rosaceae). Nonetheless, this evidence has relied mostly on patterns of cytonuclear discordance, and direct evidence from nuclear allelic markers is still needed. METHODS: Here we used PCR target enrichment in combination with high throughput sequencing to obtain multiple copies of the nuclear ribosomal (nr) DNA cistron and 45 regions of the plastid genome (cpDNA) from 219 accessions representing 48 species of Lachemilla and to explore the allopolyploid origin of species in this group. KEY RESULTS: We were able to identify multiple nrDNA ribotypes and establish clear evidence of allopolyploidy in 33 species of Lachemilla, showing that this condition is common and widespread in the genus. Additionally, we found evidence for three autopolyploid species. We also established multiple, independent origins of several allopolyploid species. Finally, based solely on the cpDNA phylogeny, we identified that the monotypic genus Farinopsis is the sister group of Lachemilla and allied genera within subtribe Fragariinae. CONCLUSIONS: Our study demonstrates the utility of the nuclear ribosomal DNA cistron to detect allopolyploidy when concerted evolution of this region is not complete. Additionally, with a robust chloroplast phylogeny in place, the direction of hybridization events can be established, and multiple, independent origins of allopolyploid species can be identified.


Assuntos
DNA Ribossômico/análise , Evolução Molecular , Genes de Plantas , Plastídeos , Poliploidia , Rosaceae/genética , Núcleo Celular/genética , DNA de Cloroplastos/análise , DNA de Cloroplastos/genética , DNA Ribossômico/genética , Genomas de Plastídeos , Genômica , Filogenia , Plastídeos/genética , Reação em Cadeia da Polimerase
14.
PLoS One ; 14(2): e0211696, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30730930

RESUMO

Tugarinovia (Family Asteraceae) is a monotypic genus. It's sole species, Tugarinovia mongolica Iljin, is distributed in the northern part of Inner Mongolia, with one additional variety, Tugarinovia mongolica var ovatifolia, which is distributed in the southern part of Inner Mongolia. The species has a limited geographical range and declining populations. To understand the phylogeographic structure of T. mongolica, we sequenced two chloroplast DNA regions (psbA-trnH and psbK-psbI) from 219 individuals of 16 populations, and investigated the genetic variation and phylogeographic patterns of T. mongolica. The results identified a total of 17 (H1-H17) chloroplast haplotypes. There were no haplotypes shared between the northern (T. mongolica) and southern groups (T. mongolica var. ovatifolia), and they formed two distinct lineages. The regional split was also supported by AMOVA and BEAST analyses. AMOVA showed the main variation that occurred between the two geographic groups. The time of divergence of the two groups can be dated to the early Pleistocene epoch, when climate fluctuations most likely resulted in the allopatric divergence of T. mongolica. The formation of the desert blocked genetic flow and enhanced the divergence of the northern and southern groups. Our results indicate that the genetic differences between T. mongolica and T. mongolica var. ovatifolia are consistent with previously proposed morphological differences. We speculate that the dry, cold climate and the expansion of the desert during the Quaternary resulted in the currently observed distribution of extant populations of T. mongolica. In the northern group, the populations Chuanjinsumu, Wuliji and Yingen displayed the highest genetic diversity and should be given priority protection. The southern group showed a higher genetic drift (FST = 1, GST = 1), and the inbreeding load (HS = 0) required protection for each population. Our results propose that the protection of T. mongolica should be implemented through in situ and ex situ conservation practices to increase the effective population size and genetic diversity.


Assuntos
Asteraceae/genética , China , Clima , DNA de Cloroplastos/genética , DNA de Plantas/genética , Fluxo Gênico/genética , Variação Genética/genética , Genética Populacional/métodos , Haplótipos/genética , Filogenia , Filogeografia/métodos , Análise de Sequência de DNA/métodos
15.
PLoS One ; 14(2): e0213023, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30811487

RESUMO

The genus Secale is small but very diverse. Despite the high economic importance, phylogenetic relationships of rye species have not been fully determined, and they are extremely important for the process of breeding of new cultivars that can be enriched with functional traits derived from wild rye species. The study analyzed the degree of relationship of 35 accessions of the genus Secale, representing 13 most often distinguished species and subspecies, originating from various seed collections in the world, based on the analysis of non-coding regions of the chloroplast (cpDNA) and mitochondrial genome (mtDNA), widely used in phylogenetic and population plant studies, because of a higher rate of evolution than the coding regions. There was no clear genetic structure between different species and subspecies, which may indicated the introgression between these taxa. The obtained data confirmed that S. vavilovii was very similar to S. cereale, which confirmed the assumption that they might share a common ancestor. The results also confirmed the divergence of S. sylvestre from other species and subspecies of rye. Areas that may be useful molecular markers in studies on closely related species of the genus Secale were also indicated.


Assuntos
Cloroplastos/genética , Variação Genética , Mitocôndrias/genética , Secale/classificação , Agricultura , Teorema de Bayes , DNA de Cloroplastos/genética , DNA Mitocondrial/genética , Evolução Molecular , Filogenia , Secale/genética , Análise de Sequência de DNA
16.
Molecules ; 24(3)2019 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-30699955

RESUMO

Kaempferia galanga and Kaempferia elegans, which belong to the genus Kaempferia family Zingiberaceae, are used as valuable herbal medicine and ornamental plants, respectively. The chloroplast genomes have been used for molecular markers, species identification and phylogenetic studies. In this study, the complete chloroplast genome sequences of K. galanga and K. elegans are reported. Results show that the complete chloroplast genome of K. galanga is 163,811 bp long, having a quadripartite structure with large single copy (LSC) of 88,405 bp and a small single copy (SSC) of 15,812 bp separated by inverted repeats (IRs) of 29,797 bp. Similarly, the complete chloroplast genome of K. elegans is 163,555 bp long, having a quadripartite structure in which IRs of 29,773 bp length separates 88,020 bp of LSC and 15,989 bp of SSC. A total of 111 genes in K. galanga and 113 genes in K. elegans comprised 79 protein-coding genes and 4 ribosomal RNA (rRNA) genes, as well as 28 and 30 transfer RNA (tRNA) genes in K. galanga and K. elegans, respectively. The gene order, GC content and orientation of the two Kaempferia chloroplast genomes exhibited high similarity. The location and distribution of simple sequence repeats (SSRs) and long repeat sequences were determined. Eight highly variable regions between the two Kaempferia species were identified and 643 mutation events, including 536 single-nucleotide polymorphisms (SNPs) and 107 insertion/deletions (indels), were accurately located. Sequence divergences of the whole chloroplast genomes were calculated among related Zingiberaceae species. The phylogenetic analysis based on SNPs among eleven species strongly supported that K. galanga and K. elegans formed a cluster within Zingiberaceae. This study identified the unique characteristics of the entire K. galanga and K. elegans chloroplast genomes that contribute to our understanding of the chloroplast DNA evolution within Zingiberaceae species. It provides valuable information for phylogenetic analysis and species identification within genus Kaempferia.


Assuntos
Alpinia/genética , DNA de Cloroplastos/genética , Genoma de Cloroplastos/genética , Zingiberaceae/genética , Composição de Bases/genética , Cloroplastos/genética , Repetições de Microssatélites/genética , Estrutura Molecular , Filogenia , Sequenciamento Completo do Genoma/métodos
17.
Mol Phylogenet Evol ; 133: 142-151, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30639766

RESUMO

Species identification and discrimination is the basis of biodiversity research. In general, it is considered that numerous nucleotide variations (e.g., whole chloroplast genomes) can identify species with higher resolution than a few loci, e.g., partial chloroplast or nuclear gene fragments. In this study, we tested this hypothesis by sampling population genetics samples of the endangered herb genus Notopterygium. We sequenced the complete plastomes, five nuclear gene regions, three chloroplast DNA fragments, and a nuclear internal transcribed spacer (nrITS) region for 18 populations sampled throughout most of the geographic ranges of all six Notopterygium species. Species identification analysis showed that four DNA barcodes (matK, rbcL, trnS-trnG, and nrITS) and/or combinations of these markers achieved Notopterygium species discrimination at higher resolution than the general plastomes and nuclear gene sequences. In particular, nrITS had the highest discriminatory power among all of the individual markers. Molecular data sets and morphological evidence indicated that all six Notopterygium species could be reclassified unambiguously to four putative species clades. N. oviforme and N. franchetii had the closest relationship. Molecular dating showed that the origin and divergence of Notopterygium species was significantly associated with geological and climatic fluctuations during the middle of the Pliocene. In conclusion, our results suggest that a few nucleotide variations can achieve species discrimination with higher resolution than numerous plastomes and general nuclear gene fragments when discerning related Notopterygium species.


Assuntos
Apiaceae/genética , Espécies em Perigo de Extinção , Loci Gênicos , Variação Genética , DNA de Cloroplastos/genética , DNA de Plantas/genética , Marcadores Genéticos , Genoma de Cloroplastos , Filogenia , Especificidade da Espécie , Fatores de Tempo
18.
Genetica ; 147(1): 57-68, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30671745

RESUMO

Magnolias are characteristic tree species of the Tropical Montane Cloud Forest (TMCF) in Mexico, an ecosystem that is highly threatened by habitat fragmentation and climate change. In this study, based on DNA sequences from five regions (chloroplast: trnT-trnL, trnK5-matK, trnS-trnG, rpl32-trnL, nuclear: ITS) and seven nuclear microsatellite markers, we aimed to delineate species boundaries between two-endemic species of the TMCF, Magnolia pedrazae and Magnolia schiedeana, and to estimate levels of genetic structure and diversity among populations. Phylogenetic and haplotype network analyses for the chloroplast and ITS regions did not support genetic differentiation as two distinctive species. Results from Bayesian and multivariate cluster analyses based on microsatellite loci showed high genetic differentiation across most populations, which was consistent with a strong and significant pattern of isolation by geographical distance. We found moderate to high levels of population genetic diversity, but it was lower in small populations relative to large populations. Our results suggest a contemporary decrease of genetic connectivity among populations, likely as a consequence of the current decline of suitable TMCF habitat. Managing landscape connectivity among remnant Magnolia populations within protected natural parks and surroundings, and with emphasis of small populations, would be key for the species conservation.


Assuntos
Especiação Genética , Genoma de Planta , Magnolia/genética , Polimorfismo Genético , DNA de Cloroplastos/genética , Haplótipos , Magnolia/química , Repetições de Microssatélites
19.
Plant Biol (Stuttg) ; 21(1): 122-132, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30195257

RESUMO

Hybridization is a widespread phenomenon present in numerous lineages across the tree of life. Its evolutionary consequences range from effects on the origin and maintenance, to the loss of biodiversity. We studied genetic diversity and intra- and interspecific gene flow between two sympatric populations of closely-related species, Pitcairnia flammea and P. corcovadensis (Bromeliaceae), which are adapted to naturally fragmented Neotropical inselbergs, based on nuclear and plastidial DNA. Our main results indicate a strong reproductive isolation barrier, although low levels of interspecific gene flow were observed in both sympatric populations. The low rates of intraspecific gene flow observed for both P. corcovadensis and P. flammea populations corroborate the increasing body of evidence that inselberg bromeliad species are maintained as discrete evolutionary units despite the presence of low genetic connectivity. Nuclear patterns of genetic diversity and gene flow revealed that hybridization and introgression might not cause species extinction via genetic assimilation of the rare P. corcovadensis. In the face of reduced intraspecific gene exchange, hybridization and introgression may be important aspects of the Pitcairnia diversification process, with a positive evolutionary impact at the bromeliad community level, and thus contribute to increasing and maintaining genetic diversity in local isolated inselberg populations.


Assuntos
Bromeliaceae/genética , Hibridização Genética , Isolamento Reprodutivo , Brasil , DNA de Cloroplastos/genética , Fluxo Gênico , Variação Genética , Geografia , Haplótipos/genética , Especificidade da Espécie
20.
Mol Phylogenet Evol ; 130: 380-396, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30240912

RESUMO

Exploring the effects of orographic events and climatic shifts on geographic distribution of organism in the Hengduan Mountains Region (HMR) and its eastern adjacent area is crucial to the understanding of the environmental changes to organismal evolution. To gain further insight into these processes, we reconstruct evolutionary history of ten species in Allium section Sikkimensia, distributed across regions abovementioned. Using chloroplast and nuclear sequence variation of 79 populations of these ten Allium species with known morphological preferences, we elucidate the phylogenetic relationship, divergence time, ancestral area and genetic structures. Climatic variables analysis, Isolation by distance (IBD) and environment (IBE) and Species distribution modeling (SDM) were analyzed along different genetic clades. These analyses indicated that the initial split of Sikkimensia was triggered by climate changes following Qinghai-Tibet Plateau sensu lato (QTPsl) uplift during the late Miocene. Subsequently, divergences within lineage (lineage A)/among lineages (lineage C and D) in Sikkimensia may be induced by the intense uplift of the HMR around 3-4 Ma and abrupt intensifying of the Asian monsoon regimes. Furthermore, Sikkimensia populations exhibited lopsided demographic history in the Last Glacial Maximum (LGM), as was indicated by the expansion of their range in the QDM and contraction in the HMR. Our findings appear to suggest that the HMR uplift could have strengthened the orographic difference between the HMR and its eastern adjacent area and led to a colder climate in the HMR, while geological topography also played an important role for taxa to respond the climate change that had taken place in the HMR and its eastern adjacent area during the Pleistocene.


Assuntos
Allium/genética , Evolução Biológica , Ecossistema , China , DNA de Cloroplastos/genética , Variação Genética , Haplótipos/genética , Filogenia , Filogeografia , Tamanho da Amostra
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