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1.
Sci Justice ; 63(5): 624-634, 2023 09.
Article de Anglais | MEDLINE | ID: mdl-37718009

RÉSUMÉ

According to criminal botany, the offender unknowingly carries plant samples from the crime scene. Therefore, studying the genetic data of plants native to the crime scene can solve many ambiguities in the criminal files. In this regard, the aim of this study was to investigate the genome of 5 endemic plants in some areas of Iran with high crime rate. Quercus brantii, Curpressus arizonica, Crataegus pentagyna, Ziziphus Spina-chtista, and Buxus hyrcana were assessed using 1 genetic fragment on plastid regions (trnH-psbA) as well as 1 gene on nuclear chromosome called ITS. The alignment of DNA sequences of trnH-psbA and ITS genes was done using BioEdit, Clustal X, and Muscle v4.0 software programs. The phylogenetic analysis was performed on aligned data using Maximum Parsimony (MP) and the Bayesian methods. The Splits Tree v.4.14.4 software program was used for phylogenetic network analysis. Finally, the data combinability test was conducted using the Incongruence Length Difference (ILD) test by PAUP* software program. All data from nrDNA ITS and trnH-psbA sequences were consistent with Information Compatibility Test (ICT) results. Moreover, the nrDNA ITS indicated more resolved relationship than trnH-psbA. The results from MP and Bayesian analyses did not differ significantly between singular and combined forms, except for a slight variance in confidence interval of branches. As the phylogenetic trees provide more thorough and deeper conception of species relations, it is hoped that they would be useful to illuminate some forensic gaps in regions with high crime rates enriched by these plants, not only in Iran, but also in all areas over the world with this vegetation.


Sujet(s)
Buxus , Crataegus , Quercus , Ziziphus , Humains , Iran , Théorème de Bayes , Codage à barres de l'ADN pour la taxonomie , Phylogenèse , ADN , Crime
2.
Front Plant Sci ; 14: 1089165, 2023.
Article de Anglais | MEDLINE | ID: mdl-36998693

RÉSUMÉ

Although the monophyly of Phedimus has been strongly demonstrated, the species relationships among approximately 20 species of Phedimus have been difficult to determine because of the uniformity of their floral characteristics and extreme variation of their vegetative characters, often accompanied by high polyploid and aneuploid series and diverse habitats. In this study, we assembled 15 complete chloroplast genomes of Phedimus species from East Asia and generated a plastome-based backbone phylogeny of the subgenus Aizoon. As a proxy for nuclear phylogeny, we reconstructed the nuclear ribosomal DNA internal transcribed spacer (nrDNA ITS) phylogeny independently. The 15 plastomes of subg. Aizoon were highly conserved in structure and organization; hence, the complete plastome phylogeny fully resolved the species relationships with strong support. We found that P. aizoon and P. kamtschaticus were polyphyletic and morphologically distinct or ambiguous species, and they most likely evolved from the two species complex. The crown age of subg. Aizoon was estimated to be 27 Ma, suggesting its origin to be in the late Oligocene; however, the major lineages were diversified during the Miocene. The two Korean endemics, P. takesimensis and P. zokuriensis, were inferred to have originated recently during the Pleistocene, whereas the other endemic, P. latiovalifolium, originated in the late Miocene. Several mutation hotspots and seven positively selected chloroplast genes were identified in the subg. Aizoon.

3.
Acta Pharmaceutica Sinica ; (12): 525-532, 2022.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-922932

RÉSUMÉ

In this study, nrDNA ITS sequences of Lycium cultivars were sequenced and used to test the existence of incomplete concerted evolution and pseudogenes. Together with 44 ITS sequences retrieved from GenBank, the pattern of base substitutions, GC content, 5.8S conserved motifs, the minimum free energy of secondary structures, nucleotide diversity and phylogenetic relationship of the samples were analyzed. While 83 of the 144 sequences were identified as pseudogenes, the results suggested a high degree of polymorphism and putative pseudogenes in Lycium, suggesting an incomplete concerted evolution of the ITS region. ITS polymorphism and pseudogene of Lycium were systematically tested for the first time. This research provides a references for ITS sequence to be used in the study of Lycium germplasm resources and DNA barcode identification.

4.
Plants (Basel) ; 10(4)2021 Apr 09.
Article de Anglais | MEDLINE | ID: mdl-33918962

RÉSUMÉ

The genus Silene L. is one of the largest genera in Caryophyllaceae, and is distributed in the Northern Hemisphere and South America. The endemic species Silene leucophylla and the near-endemic S. schimperiana are native to the Sinai Peninsula, Egypt. They have reduced population size and are endangered on national and international scales. These two species have typically been disregarded in most studies of the genus Silene. This research integrates the Scanning Electron Microscope (SEM), species micromorphology, and the phylogenetic analysis of four DNA markers: ITS, matK, rbcL and psb-A/trn-H. Trichomes were observed on the stem of Silene leucophylla, while the S. schimperiana has a glabrous stem. Irregular epicuticle platelets with sinuate margin were found in S. schimperiana. Oblong, bone-shaped, and irregularly arranged epidermal cells were present on the leaf of S. leucophylla, while Silene schimperiana leaf has "tetra-, penta-, hexa-, and polygonal" epidermal cells. Silene leucophylla and S. schimperiana have amphistomatic stomata. The Bayesian phylogenetic analysis of each marker individually or in combination represented the first phylogenetic study to reveal the generic and sectional classification of S. leucophylla and S. schimperiana. Two Silene complexes are proposed based on morphological and phylogenetic data. The Leucophylla complex was allied to section Siphonomorpha and the Schimperiana complex was related to section Sclerocalycinae. However, these two complexes need further investigation and more exhaustive sampling to infer their complex phylogenetic relationships.

5.
Int J Legal Med ; 135(4): 1407-1411, 2021 Jul.
Article de Anglais | MEDLINE | ID: mdl-33506296

RÉSUMÉ

In recent years, recorded cases related to forensic botany and, in particular, of plant poisoning have become rare. We report on the medicolegal characteristics of an undetermined sudden death (USD) of a woman in which scene there were remnants of a vegetal peeling. After the autopsy, macroscopic findings reported multiorgan failure and requested the investigation of the cause of death. Postmortem blood was firstly investigated on cyanide toxicity presumptively coming from a yucca-like root; however, found cyanide levels were under normality. Because of the lack of morphological features of the encountered plant remains, a genetic nrDNA ITS2 sequence investigation was followed. The resulting DNA sequence could identify the evidence as the water dropwort (Oenanthe spp.) which contains oenanthotoxin, a potent toxin that may be fatal, similar to the more commonly found in hemlock Conium or cowbane Cicuta species. A liquid chromatography-tandem high resolution mass spectrometry (LC-QTOF MS) was later applied to analyse the vegetal extract and stomach content and successfully confirmed the toxin existence. Medicolegal and analytical findings at the forensic laboratory were described, where both biological and chemical techniques could successfully conjugate, as an interdisciplinary research, and explain premortem symptoms and postmortem findings. Present data can be helpful in future investigation on poisoning cases by conjugated polyacetylenes . The present work tries to emphasize the often undervalued plant evidence in legal medicine diagnosis in the context of an unexplained death.


Sujet(s)
Mort subite/étiologie , Ènediynes/intoxication , Alcools gras/intoxication , Génétique légale , Toxicologie médicolégale , Oenanthe/intoxication , Intoxication par les plantes , Sujet âgé de 80 ans ou plus , Chromatographie en phase liquide , Codage à barres de l'ADN pour la taxonomie , Femelle , Humains , Spectrométrie de masse en tandem
6.
Am J Bot ; 106(11): 1499-1518, 2019 11.
Article de Anglais | MEDLINE | ID: mdl-31639199

RÉSUMÉ

PREMISE: Disjunct distributions have been commonly observed in mountain plant species and have stimulated phylogeographic and phylogenetic research. Here we studied Alyssum repens, a member of the polyploid species complex A. montanum-A. repens, which exhibits SE Alpine-Carpathian disjunctions with a large elevational span and consists of diploid and tetraploid populations. We aimed to investigate the species' genetic and cytotype structure in the context of its distribution patterns, to elucidate the polyploid origins and to propose an appropriate taxonomic treatment. METHODS: We combined AFLP fingerprinting markers, sequence variation of the highly repetitive ITS region of rDNA and the low-copy DET1 nuclear gene, genome size, and morphometric data. RESULTS: We identified four geographically structured genetic lineages. One consisted of diploid populations from the foothills of the Southeastern Alps and neighboring regions, and the three others were allopatric montane to alpine groups comprising diploids and tetraploids growing in the Southeastern Carpathians and the Apuseni Mts. in Romania. CONCLUSIONS: We inferred a vicariance scenario associated with Quaternary climatic oscillations, accompanied by one auto- and two allopolyploidization events most likely involving a northern Balkan relative. Whereas genetic differentiation and allopatric distribution would favor the taxonomic splitting of this species, the genetic lineages largely lack morphological distinguishability, and their ecological, cytotype and genome size divergence is only partial. Even though we probably face here a case of incipient speciation, we propose to maintain the current taxonomic treatment of Alyssum repens as a single, albeit variable, species.


Sujet(s)
Diploïdie , Polyploïdie , Analyse de polymorphisme de longueur de fragments amplifiés , Variation génétique , Humains , Phylogenèse , Phylogéographie
7.
Plants (Basel) ; 8(7)2019 Jul 08.
Article de Anglais | MEDLINE | ID: mdl-31288447

RÉSUMÉ

The genus Blumea is one of the most economically important genera of Inuleae (Asteraceae) in China. It is particularly diverse in South China, where 30 species are found, more than half of which are used as herbal medicines or in the chemical industry. However, little is known regarding the phylogenetic relationships and molecular evolution of this genus in China. We used nuclear ribosomal DNA (nrDNA) internal transcribed spacer (ITS) and chloroplast DNA (cpDNA) trnL-F sequences to reconstruct the phylogenetic relationship and estimate the divergence time of Blumea in China. The results indicated that the genus Blumea is monophyletic and it could be divided into two clades that differ with respect to the habitat, morphology, chromosome type, and chemical composition of their members. The divergence time of Blumea was estimated based on the two root times of Asteraceae. The results indicated that the root age of Asteraceae of 76-66 Ma may maintain relatively accurate divergence time estimation for Blumea, and Blumea might had diverged around 49.00-18.43 Ma. This common ancestor had an explosive expansion during the Oligocene and Miocene and two major clades were differentiated during these epochs 29.60 Ma (17.76-45.23 Ma 95% HPD (Highest Posterior Density). Evidence from paleogeography and paleoclimate studies has confirmed that Blumea experienced differentiation and an explosive expansion during the Oligocene and Miocene.

8.
Plant Biol (Stuttg) ; 21(6): 1072-1082, 2019 Nov.
Article de Anglais | MEDLINE | ID: mdl-31349366

RÉSUMÉ

Introgression is a poorly understood evolutionary outcome of hybridisation because it may remain largely undetected whenever it involves the transfer of small parts of the genome from one species to another. Aiming to understand the early stages of this process, a putative case from the southernmost border of the Armeria pungens range from its congener A. macrophylla is revisited following the discovery of a subpopulation that does not show phenotypic signs of introgression and resembles typical A. pungens. We analysed morphometrics, nuclear ribosomal DNA ITS and plastid DNA (trnL-trnF) sequences, genome size, 45S and 5S rDNA loci-FISH data and nrDNA IGS sequences. Within the study site, most individuals match morphologies of either of the two hybridising species, particularly the new subpopulation, with intermediate phenotypes being scarce. This pattern does not fully fit molecular evidence revealing two ITS ribotypes co-occurring intragenomically in most plants from the study site and one single plastid haplotype. Genome size and structural features of the IGS sequences both indicate that A. pungens from the study site is genetically more similar to its sympatric congener than to the remainder of its conspecifics. Introgression of A. macrophylla into A. pungens and plastid capture explain all the evidence analysed. However, important features to understand the origin and fate of the introgressed population, such as the degree and direction of introgression, which are important for understanding early stages of hybridisation in plants with low reproductive barriers, should be addressed with new data.


Sujet(s)
ADN ribosomique/métabolisme , Plumbaginaceae/métabolisme , ADN ribosomique/génétique , Évolution moléculaire , Génome végétal/génétique , Hybridation génétique , Plastes/génétique , Plastes/métabolisme , Plumbaginaceae/génétique , Analyse de séquence d'ADN
9.
Mol Phylogenet Evol ; 129: 189-201, 2018 12.
Article de Anglais | MEDLINE | ID: mdl-30172008

RÉSUMÉ

Hybridization and polyploidization represent an important speciation mechanism in the diploid-polyploid complex of the Chenopodium album aggregate. In the present study we successfully reconstructed the evolutionary histories of the majority of Eurasian representatives of the C. album aggregate, resulting in the most comprehensive phylogenetic analysis of this taxonomically intricate group of species to date. We applied a combination of classical karyology for precise chromosome number determination, genomic in-situ hybridization for the determination of genomic composition, flow cytometry for the estimation of genome size and sequencing of plastid (cpDNA) and nuclear (ribosomal internal transcribed spacer - ITS and the introns of the FLOWERING LOCUS T LIKE genes - FTL) markers for a phylogenetic reconstruction and the identification of parental genomes in polyploid taxa. The FTL markers identified eight well supported evolutionary lineages. Five of them include at least one diploid species, and the remaining three comprise solely the subgenomes of polyploids that probably represent extinct or unknown diploid taxa. The existence of eight basic diploid lineages explains the origin of seven Eurasian polyploid groups and brings evidence of a nearly unlimited number of subgenomic combinations. The supposed promiscuity generated new species wherever different diploid lineages met each other and gave rise to tetraploid species or whenever they met other tetraploid species to produce hexaploid species throughout their evolutionary history. Finally, we unravelled a surprisingly simple scheme of polyploid species formation within the C. album aggregate. We determined seven groups of polyploid species differing in their origin in either Eurasia or Africa and convincingly demonstrated that (1) all Chenopodium polyploid species under study are of allopolyploid origin, (2) there are eight major monophyletic evolutionary lineages represented by extant or extinct/unknown diploid taxa, (3) those monophyletic lineages represent individual subgenomes, (4) hybridization among the lineages created seven subgenomic combinations of polyploid taxa, (5) taxa represented by particular subgenome combinations were further subjected to diversification, and (6) the majority of species are relatively young, not exceeding the age of the Quaternary period.


Sujet(s)
Chenopodium album/cytologie , Chenopodium album/génétique , Hybridation génétique , Polyploïdie , Séquence nucléotidique , Chromosomes de plante/génétique , Évolution moléculaire , Locus génétiques , Marqueurs génétiques , Taille du génome , Phylogenèse , Tétraploïdie
10.
PeerJ ; 5: e2931, 2017.
Article de Anglais | MEDLINE | ID: mdl-28289556

RÉSUMÉ

We estimated the genetic diversity of 50 Jatropha curcas samples from the Costa Rican germplasm bank using 18 EST-SSR, one G-SSR and nrDNA-ITS markers. We also evaluated the phylogenetic relationships among samples using nuclear ribosomal ITS markers. Non-toxicity was evaluated using G-SSRs and SCARs markers. A Neighbor-Joining (NJ) tree and a Maximum Likelihood (ML) tree were constructed using SSR markers and ITS sequences, respectively. Heterozygosity was moderate (He = 0.346), but considerable compared to worldwide values for J. curcas. The PIC (PIC = 0.274) and inbreeding coefficient (f =  - 0.102) were both low. Clustering was not related to the geographical origin of accessions. International accessions clustered independently of collection sites, suggesting a lack of genetic structure, probably due to the wide distribution of this crop and ample gene flow. Molecular markers identified only one non-toxic accession (JCCR-24) from Mexico. This work is part of a countrywide effort to characterize the genetic diversity of the Jatropha curcas germplasm bank in Costa Rica.

11.
Pharmacogn Mag ; 10(40): 385-90, 2014 Oct.
Article de Anglais | MEDLINE | ID: mdl-25422535

RÉSUMÉ

BACKGROUND: Peucedanum praeruptorum L., a traditional Chinese medicine known as Qian-hu, is commonly used for dispelling wind-heat and expectorant and loss of energy. However, due to similar morphological characters and high market demand, there are many substitutes and adulterants of P. praeruptorum. DNA barcoding is an approach to identify species based on sequences from a short, standardized DNA region. OBJECTIVE: To authenticate P. praeruptorum from its substitutes and adulterants. MATERIALS AND METHODS: The differential identification of P. praeruptorum and 13 regional substitutes and 23 adulterants was investigated by means of DNA sequence analysis of internal transcribed spacer (ITS) region of the nuclear ribosomal DNA (nrDNA), a bootstrap neighbor-joining (NJ) tree according to Kimura's 2-parameter method was also calculated. RESULTS: The data showed that P. praeruptorum, its substitutes and adulterants could be easily distinguished at the DNA level, while almost all species were well resolved, and successfully identified on the NJ tree. CONCLUSION: The ITS sequence can be used for the identification of P. praeruptorum and to distinguish it from common substitutes and adulterants.

12.
Article de Chinois | WPRIM (Pacifique Occidental) | ID: wpr-855049

RÉSUMÉ

Objective: To study the genetic diversity of 17 samples of Gentiana straminea from different habitats of Tibet. Methods: Sampling in populations was carried out, and the related species G. crassicaulis from the same area was as the out group; nr DNA ITS sequences were amplified and analyzed; UPGMA systematic tree was constructed. Results: One polymorphic site of G. straminea from Tibet was found; the six samples of out group have the identical DNA ITS sequences. Conclusion: The difference between G. straminea and the out group is obvious; seventeen samples of G. straminea from different habitats are divided into two groups; genetic diversity is more abundant; the result could provide the basic reference for the quality evaluation and the construction of core germplasm of G. straminea in Tibet.

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