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1.
Planta Med ; 90(7-08): 534-545, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38843793

RESUMEN

Chamomile (Matricaria chamomilla) is an important medicinal plant whose beneficial activities partly rely on certain flavonoids. The first dedicated step in flavonoid biosynthesis is chalcone synthase (CHS, EC 2.3.1.74). The genomic DNA of CHS was studied in six chamomile specimens from different genotypes to describe interspecimen, as well as interspecific, variability. One specimen of M. discoidea was included as an outgroup. The two exons of CHS of M. chamomilla (McCHS) and M. discoidea (MdCHS) were 188 bp and 1,011 bp long, separated by an intron of variable length between 192 and 199 bp in McCHS and 201 bp in MdCHS, respectively. The two exons with 5.3 and 6.2 mutations per 100 bp, respectively, were more conserved than the intron with 11.5 mutations per 100 bp. In total, 96 SNPs were detected in both species, of which 12 SNPs were only present in MdCHS and 80 SNPs only in McCHS. Overall, 70 haplotypes (multilocus genotypes, MLGs) were detected. The samples could be classified into two groups, a 'compact' group of a low number and diversity of haplotypes and a 'variable' group of a high number and diversity of haplotypes. Of the 74 SNPs in McCHS, only six SNPs were non-synonymous. However, the amino acid changes did not affect critical areas of the enzyme. The combination of the six SNPs resulted in nine translated amino acid MLGs. The CHS network located MdCHS, due to the crossing barrier, quite distant from chamomile. MdCHS docked to McCHS at a position from where McCHS divergently evolved into two directions.


Asunto(s)
Aciltransferasas , Matricaria , Aciltransferasas/genética , Aciltransferasas/metabolismo , Matricaria/genética , Matricaria/enzimología , Polimorfismo de Nucleótido Simple , Haplotipos , Variación Genética , ADN de Plantas/genética , Genotipo , Filogenia , Intrones
2.
Br J Clin Pharmacol ; 87(3): 916-924, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32598074

RESUMEN

AIMS: The clinically investigated rationale for neprilysin (NEP)-inhibition by angiotensinreceptor-NEPinhibitor (ARNi) therapy is to induce elevations in endogenous natriuretic peptides. NEP, however, cleaves a broad spectrum of substrates, which partially hold significant implications in heart failure with reduced ejection fraction (HFrEF). The effect of NEP inhibition on these peptides has not been investigated thoroughly. This study explored the response of adrenomedullin (ADM) regulation to the initiation of ARNi. METHODS: Seventy-four patients with stable HFrEF and initiation of ARNi were prospectively enrolled, 67 patients on continuous angiotensin-converting-enzyme inhibitor(ACEi)/angiotensin-receptor blocker (ARB) therapy served as control. Plasma bioactive-ADM (bio-ADM), mid-regional-pro-ADM (MR-proADM), B-typenatriuretic peptide (BNP) and N-terminal-pro-BNP (NT-proBNP) were determined at baseline, short-term, 1-year and 2-year follow up. RESULTS: Following ARNi initiation both bio-ADM and MR-proADM concentrations were significantly increased at early and long-term follow up (bio-ADM [pg/mL]: 26.0 [interquartile range {IQR}: 17.7-37.5] vs. 50.8 [IQR: 36.5-78.1] vs. 54.6 [IQR: 42.0-97.1] vs. 57.4 [IQR: 48.5-161.6]; MR-proADM [nmol/L]: 0.87 [IQR: 0.64-1.12] vs. 1.25 [IQR: 0.93-1.79] vs. 1.42 [IQR: 0.95-1.90] vs. 1.60 [IQR: 1.12-2.46], P < .0001 for all). The ratios bio-ADM/MR-proADM and BNP/NT-proBNP increased during ARNi-therapy proving improved availability of bioactive peptides. The proportional increase of bio-ADM markedly exceeded BNP increase. Patients converted to ARNi showed similar biomarker patterns irrespective of baseline renin-angiotensin system blocker therapy, i.e. ACEi or ARB (P > .05 for all), indicating that activation of the ADM-axis arises particularly from NEPinhibition. CONCLUSION: The significant increase of MR-proADM and bio-ADM together with an elevated bioADM/MR-proADM ratio suggest both enhanced formation and reduced breakdown of bioactive ADM following the initiation of ARNi. Activation of the ADM-axis represents a so far unrecognized effect of ARNi.


Asunto(s)
Insuficiencia Cardíaca Sistólica , Insuficiencia Cardíaca , Adrenomedulina , Antagonistas de Receptores de Angiotensina/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Angiotensinas , Biomarcadores , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca Sistólica/tratamiento farmacológico , Humanos , Péptido Natriurético Encefálico , Neprilisina , Fragmentos de Péptidos , Receptores de Angiotensina , Volumen Sistólico
3.
Planta Med ; 86(15): 1148-1155, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32492718

RESUMEN

The genus Cistus is taxonomically complex, as taxonomic classification of individual species based on morphological criteria is often difficult and ambiguous. However, specific species contain valuable natural products, especially terpenoids and polyphenols, which exert various biological effects and might therefore be used for treatment of a broad array of disorders. Hence, a fast and reliable method for clear identification of different Cistus (sub-) species is required. Approaches for analysis of secondary metabolite profiles, e.g., with NMR, might remedy the challenging classification of Cistus (sub-) species and help to identify specific markers for differentiation between them. In the present study, 678 samples from wild-growing Cistus populations, including 7 species and 6 subspecies/varieties thereof, were collected in 3 years from populations in 11 countries all over the Mediterranean basin. Samples were extracted with buffered aqueous methanol and analysed with NMR. From the resulting 1D-1H-NOESY and J-Res profile spectra, marker signals or spectral regions for the individual (sub-) species were identified with multivariate statistical tools. By examining the NMR profiles of these extracts, we were able to identify discriminators and specific markers for the investigated Cistus (sub-) species. Various influencing factors, like (sub-) species, wild harvestings of different populations from several countries, numerous collection sites, different years, and cultivation in greenhouses have been considered in this work. As the here identified markers are independent from these influencing factors, the results can be considered a robust model and might be used for future differentiation between Cistus (sub-) species.


Asunto(s)
Cistaceae , Cistus , Extractos Vegetales , Polifenoles , Terpenos
4.
Mar Drugs ; 17(10)2019 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-31614490

RESUMEN

A glycopeptide fraction (GPF) from internal organs of green sea urchins (Strongylocentrotus droebachiensis Müller, Strongylocentrotidae) has been reported to be an effective bronchitis treatment. In this study, we evaluated the pharmacokinetic and tissue distribution of GPF, following single and repeated intranasal (i/n) administration over the course of seven days in rats. The method measuring lactate dehydrogenase as biomarker was used to analyse the plasma and tissue concentrations of GPF. GPF appears in the plasma 15 min after single i/n administration (100 µg/kg) and reaches its maximum at 45 min. The area under the curve (AUC)0-24 and Cmax were similar using both i/n and intravenous administration, while mean residence time (MRT) and T1/2 after i/n administration were significantly higher compared with intravenous (i/v) administration. The absolute bioavailability of GPF after i/n administration was 89%. The values of tissue availability (ft) provided evidence about the highest concentration of GPF in the nose mucosa (ft = 34.9), followed by spleen (ft = 4.1), adrenal glands (ft = 3.8), striated muscle (ft = 1.8), kidneys (ft = 0.5), and liver (ft = 0.3). After repeated dose administration, GPF exhibited significantly higher AUC0-24 and MRT, indicating its accumulation in the plasma.


Asunto(s)
Biomarcadores/metabolismo , Glicopéptidos/farmacocinética , Strongylocentrotus/metabolismo , Administración Intranasal , Animales , Área Bajo la Curva , Disponibilidad Biológica , Inyecciones Intravenosas , Masculino , Plasma/metabolismo , Ratas , Distribución Tisular/fisiología
5.
Clin Chem ; 64(3): 597-608, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29138270

RESUMEN

BACKGROUND: Blockade of the renin-angiotensin system (RAS) represents a main strategy in the therapy of heart failure with reduced ejection fraction (HFrEF), but the role of active renin concentration (ARC) for guiding therapy in the presence of an RAS blockade remains to be established. This study assessed angiotensin profiles of HFrEF patients with distinct RAS activations as reflected by ARC. METHODS: Two cohorts of stable chronic HFrEF patients on optimal medical treatment (OMT) were enrolled. We assessed ARC and all known circulating angiotensin metabolites, including AngI and AngII, by mass spectrometry to investigate the effect of different therapy modalities. Low- and high-renin HFrEF patients were identified by ARC screening and subsequently characterized by their angiotensin profiles. RESULTS: Although different modes of RAS blockade resulted in typical AngII/AngI ratios, concentrations of (AngI+AngII) strongly correlated with ARC [r = 0.95, P < 0.001] independent of therapy mode. Despite RAS blocker treatment with angiotensin-converting enzyme inhibitors (ACE-I) or angiotensin II type 1 receptor blockers (ARB), which anticipated ARC upregulation, about 30% of patients showed lower/normal range ARC values. ARC did not correlate with N-terminal pro-B-type natriuretic peptide (NT-proBNP) concentrations and New York Heart Association (NYHA) stages. Angiotensin concentrations were profoundly diminished for the low-ARC group compared with the high-ARC group: AngI [6.4 ng/L (IQR: 2.1-12.5) vs 537.9 ng/L (IQR: 423.1-728.4), P < 0.001 for ACE-I; and 4.5 ng/L (IQR: 1.4-11.2) vs 203.0 ng/L (IQR: 130.2-247.9), P = 0.003 for ARB] and AngII [<1.4 ng/L (IQR: <1.4-1.5) vs 6.1 ng/L (IQR: 2.0-11.1), P = 0.002 for ACE-I and 4.7 ng/L (IQR: <1.4-12.3) vs 206.4 ng/L (IQR: 142.2-234.4), P < 0.001 for ARB]. CONCLUSIONS: In addition to NT-proBNP and NYHA stages, ARC enables classification of HFrEF patients receiving OMT into more distinguished neurohumoral HFrEF phenotypes, offering a rationale for adaptive therapeutic interventions.


Asunto(s)
Insuficiencia Cardíaca/tratamiento farmacológico , Renina/sangre , Anciano , Angiotensina I/sangre , Angiotensina II/sangre , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Femenino , Insuficiencia Cardíaca/sangre , Humanos , Masculino , Persona de Mediana Edad , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Fenotipo , Sistema Renina-Angiotensina/efectos de los fármacos
6.
Planta Med ; 84(6-07): 428-433, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29165730

RESUMEN

Quality control of drugs consists of identifying the raw material to avoid unwanted admixtures or exchange of material as well as looking for abiotic and biotic contaminations. So far, identity and microbial contamination are analyzed by separate processes and separate methods. Species identification by their DNA ("DNA barcoding") has the potential to supplement existing methods of identification. The introduction of next-generation sequencing methods offers completely new approaches like the identification of whole communities in one analysis, termed "DNA metabarcoding". Here we present a next-generation sequencing assessment to identify plants and fungi of two commercial sage samples (Salvia officinalis) using the standard DNA barcoding region "internal transcribed spacer" consisting of internal transcribed spacer 1 and internal transcribed spacer 2, respectively. The main species in both samples was identified as S. officinalis. The spectrum of accompanying plant and fungal species, however, was completely different between the samples. Additionally, the composition between internal transcribed spacer 1 and internal transcribed spacer 2 within the samples was different and demonstrated the influence of primer selection and therefore the need for harmonization. This next-generation sequencing approach does not result in quantitative species composition but gives deeper insight into the composition of additional species. Therefore, it would allow for a better knowledge-based risk assessment than any other method available. However, the method is only economically feasible in routine analysis if a high sample throughput can be guaranteed.


Asunto(s)
Código de Barras del ADN Taxonómico/métodos , Salvia officinalis/genética , ADN de Plantas/genética , Contaminación de Medicamentos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Reacción en Cadena de la Polimerasa/métodos , Control de Calidad , Salvia officinalis/microbiología
7.
ScientificWorldJournal ; 2016: 5393079, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27579344

RESUMEN

The principal aim of this study was to analyze the chemical composition and qualitative and quantitative variability of essential oils obtained from seven naturally grown populations of the Pinus peuce Grisebach, Pinaceae in Kosovo. Plant materials were collected from three populations in the Sharri National Park and from four other populations in the Bjeshkët e Nemuna National Park, in Kosovo. Essential oils were obtained by steam distillation and analyzed by GC-FID (Gas Chromatography-Flame Ionization Detection) and GC-MS (Gas Chromatography-Mass Spectrometry). The results showed that the yield of essential oils (v/w dry weight) varied depending on the origin of population and the plant organs and ranged from 0.7 to 3.3%. In total, 51 compounds were identified. The main compounds were α-pinene (needles: 21.6-34.9%; twigs: 11.0-24%), ß-phellandrene (needles: 4.1-27.7; twigs: 29.0-49.8%), and ß-pinene (needles: 10.0-16.1; twigs: 6.9-20.7%). HCA (Hierarchical Cluster Analysis) and PCA (Principal Component Analyses) were used to assess geographical variations in essential oil composition. Statistical analysis showed that the analyzed populations are grouped in three main clusters which seem to reflect microclimatic conditions on the chemical composition of the essential oils.


Asunto(s)
Aceites Volátiles/química , Pinus/química , Cromatografía de Gases y Espectrometría de Masas , Kosovo , Parques Recreativos
8.
New Phytol ; 205(1): 415-28, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25209139

RESUMEN

This study analyses and compares the genetic signatures of anagenetic and cladogenetic speciation in six species of the genus Robinsonia (Asteraceae, Senecioneae), endemic to the Juan Fernández Islands, Chile. Population genetic structure was analyzed by amplified fragment length polymorphism (AFLP) and microsatellite (simple sequence repeat, SSR) markers from 286 and 320 individuals, respectively, in 28 populations. Each species is genetically distinct. Previous hypotheses of classification among these species into subgenera and sections, via morphological, phytochemical, isozymic and internal transcribed spacer (ITS) data, have been confirmed, except that R. saxatilis appears to be related to R. gayana rather than R. evenia. Analysis of phylogenetic results and biogeographic context suggests that five of these species have originated by cladogenesis and adaptive radiation on the older Robinson Crusoe Island. The sixth species, R. masafuerae, restricted to the younger Alejandro Selkirk Island, is closely related to and an anagenetic derivative of R. evenia from Robinson Crusoe. Microsatellite and AFLP data reveal considerable genetic variation among the cladogenetically derived species of Robinsonia, but within each the genetic variation is lower, highlighting presumptive genetic isolation and rapid radiation. The anagenetically derived R. masafuerae harbors a level of genetic variation similar to that of its progenitor, R. evenia. This is the first direct comparison of the genetic consequences of anagenetic and cladogenetic speciation in plants of an oceanic archipelago.


Asunto(s)
Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Asteraceae/genética , Especiación Genética , Repeticiones de Microsatélite/genética , Chile , Variación Genética , Geografía , Filogenia , Especificidad de la Especie
9.
Mol Cell Probes ; 29(6): 343-350, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26493217

RESUMEN

Masterwort (Peucedanum ostruthium, syn. Imperatoria ostruthium, Apiaceae) is an old economic plant in Alpine countries cultivated as ornamental plant and used for spirits and in folk medicine. P. ostruthium is a species that has often been confused with related Apiaceae species or morphologically similar roots or tubers resulting in products of minor quality. Masterwort can be distinguished from other Apiaceae species by nrDNA (ITS1 and ITS2). The analysed chloroplast markers (trnK 5' intron, trnT-trnL, and psbA-trnH), however, showed no species-specific mutations. With the application of two primer pairs amplifying parts of ITS and developed for high-resolution melting curve analysis (HRM) the target species was distinguishable from the other Peucedanum and Apiaceae species of our reference set. A multiplex PCR/HRM was developed to detect adulterations with Gentiana spp., Aconitum napellus and Veratrum album.


Asunto(s)
Apiaceae/clasificación , ADN de Plantas/análisis , Reacción en Cadena de la Polimerasa Multiplex/métodos , Apiaceae/genética , ADN de Cloroplastos/análisis , ADN Espaciador Ribosómico/genética , Raíces de Plantas/genética , Especificidad de la Especie
10.
J Plant Res ; 128(1): 73-90, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25292282

RESUMEN

A common mode of speciation in oceanic islands is by anagenesis, wherein an immigrant arrives and through time transforms by mutation, recombination, and drift into a morphologically and genetically distinct species, with the new species accumulating a high level of genetic diversity. We investigate speciation in Drimys confertifolia, endemic to the two major islands of the Juan Fernández Archipelago, Chile, to determine genetic consequences of anagenesis, to examine relationships among populations of D. confertifolia and the continental species D. winteri and D. andina, and to test probable migration routes between the major islands. Population genetic analyses were conducted using AFLPs and nuclear microsatellites of 421 individuals from 42 populations from the Juan Fernández islands and the continent. Drimys confertifolia shows a wide genetic variation within populations on both islands, and values of genetic diversity within populations are similar to those found within populations of the continental progenitor. The genetic results are compatible with the hypothesis of high levels of genetic variation accumulating within anagenetically derived species in oceanic islands, and with the concept of little or no geographical partitioning of this variation over the landscape. Analysis of the probability of migration within the archipelago confirms colonization from the older island, Robinson Crusoe, to the younger island Alejandro Selkirk.


Asunto(s)
Drimys/genética , Especiación Genética , Islas , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Chile , Variación Genética , Genética de Población , Geografía , Repeticiones de Microsatélite/genética , Modelos Biológicos , Filogenia
11.
Chem Biodivers ; 12(11): 1706-17, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26567948

RESUMEN

Ripe cones of Juniperus communis L. (Cupressaceae) were collected from five wild populations in Kosovo, with the aim of investigating the chemical composition and natural variation of essential oils between and within wild populations. Ripe cones were collected, air dried, crushed, and the essential oils obtained by hydrodistillation. The essential-oil constituents were identified by GC-FID and GC/MS analyses. The yield of essential oil differed depending on the population origins and ranged from 0.4 to 3.8% (v/w, based on the dry weight). In total, 42 compounds were identified in the essential oils of all populations. The principal components of the cone-essential oils were α-pinene, followed by ß-myrcene, sabinene, and D-limonene. Taking into consideration the yield and chemical composition, the essential oil originating from various collection sites in Kosovo fulfilled the minimum requirements for J. communis essential oils of the European Pharmacopoeia. Hierarchical cluster analysis (HCA) and principal component analysis (PCA) were used to determine the influence of the geographical variations on the essential-oil composition. These statistical analyses suggested that the clustering of populations was not related to their geographic location, but rather appeared to be linked to local selective forces acting on the chemotype diversity.


Asunto(s)
Juniperus/química , Aceites Volátiles/química , Aceites de Plantas/química , Análisis por Conglomerados , Kosovo , Aceites Volátiles/aislamiento & purificación , Aceites de Plantas/aislamiento & purificación , Análisis de Componente Principal
12.
Physiol Mol Biol Plants ; 21(1): 117-22, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25650329

RESUMEN

Primula veris L. (Primulaceae) is a long lived perennial and well known pharmaceutical plant, widely collected for these reasons in almost all SE Europe and particularly in Kosovo. The aim of the study is to determine molecular polymorphism of cowslip (P. veris L.) populations from Kosovo. DNA extracted from leaves were  investigated in details for presence of polymorphism. RAPD analyses were conducted using 20 different short primers. Genomic DNA amplification profiles were analyzed and processed using data labelling. Comparison between cowslip populations in genetic composition revealed that samples from Bogaj were too distinct on their own. Molecular variation was observed to be more within populations (73 %) as compared to among populations (27 %). On the other hand, genetic distance of populations revealed that the highest genetic distance is between Leqinat and Maja e Madhe. Mean values of expected heterozygosity were highest in Bogaj population, while lowest in Maja e Madhe population. The obtained results indicated that Bogaj population are more polymorphic. From the obtained data it can be concluded that RAPD markers provided a useful technique to study genetic diversity in P. veris L. populations. This technology allows identification and assessment of the genetic similarities and differences among plant populations.

13.
Planta Med ; 80(5): 415-8, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24652524

RESUMEN

Notopterygium roots (Qiang Huo) have been used in traditional Chinese medicine for treating colds, inflammatory diseases like rheumatoid arthritis, and as an analgesic. The anti-inflammatory activity of the roots of Notopterygium incisum has been evaluated by testing the inhibitory activity on nitric oxide production by inducible nitric oxide synthase. The apparent authenticity of the sample was checked by DNA sequence comparison. Using activity-guided isolation, different compounds were isolated and structurally characterized by means of NMR and mass spectroscopy. Eight polyacetylenes could be identified and were tested on their inhibitory activity on nitric oxide production in RAW 264.7 mouse macrophages using the Griess assay. Different 3-hydroxy allyl polyacetylenes exhibited significant activity (IC50: 8-acetoxyfalcarinol, 20.1 µM; falcarindiol, 9.2 µM; 9-epoxyfalcarindiol, 8.8 µM; and crithmumdiol, 23.6 µM).


Asunto(s)
Apiaceae/química , Óxido Nítrico/biosíntesis , Raíces de Plantas/química , Poliinos/farmacología , Animales , Línea Celular , Técnicas In Vitro , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Ratones , Datos de Secuencia Molecular , Óxido Nítrico Sintasa de Tipo II/metabolismo , Poliinos/aislamiento & purificación
14.
Plants (Basel) ; 13(7)2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38611450

RESUMEN

Indigo quality is determined by its indigotin content. Another quality indicator is colour. For an evaluation of species, indigo samples from Indigofera tinctoria, Indigofera suffruticosa, Indigofera arrecta, Persicaria tinctoria, Strobilanthes cusia and Wrightia laevis cultivated in Austria and China were visually classified and analysed spectrophotometrically and using a L*a*b* measuring device. In addition to a standardised hot-extraction method without lime, some samples were extracted simulating traditional methods at ambient temperatures using lime. The highest indigotin contents were achieved with Indigofera arrecta (55%, Austria) and Strobilanthes cusia (56%, China). There were no statistically significant differences between the indigo extraction yields of the species cultivated in Austria, but Indigofera arrecta and Persicaria tinctoria had statistically significantly higher indigotin extraction yields than Indigofera tinctoria and Indigofera suffruticosa. From the species extracted in China, Strobilanthes cusia showed higher values in all parameters than Indigofera tinctoria, Indigofera suffruticosa and Wrightia laevis. Compared with the standardised method, the method simulating local practice yielded more indigo but had a lower indigotin content; the indigotin extraction yields did not differ greatly. L*a*b* values enabled precise estimations of the indigotin content, making it an interesting option for quality control, as inexpensive, easy-to-handle L*a*b* measuring instruments have become available.

15.
Genome Biol ; 25(1): 141, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38807159

RESUMEN

BACKGROUND: Reproductive isolation can result from adaptive processes (e.g., ecological speciation and mutation-order speciation) or stochastic processes such as "system drift" model. Ecological speciation predicts barriers to gene flow between populations from different environments, but not among replicate populations from the same environment. In contrast, reproductive isolation among populations independently adapted to the same/similar environment can arise from both mutation-order speciation or system drift. RESULTS: In experimentally evolved populations adapting to a hot environment for over 100 generations, we find evidence for pre- and postmating reproductive isolation. On one hand, an altered lipid metabolism and cuticular hydrocarbon composition pointed to possible premating barriers between the ancestral and replicate evolved populations. On the other hand, the pronounced gene expression differences in male reproductive genes may underlie the postmating isolation among replicate evolved populations adapting to the same environment with the same standing genetic variation. CONCLUSION: Our study confirms that replicated evolution experiments provide valuable insights into the mechanisms of speciation. The rapid emergence of the premating reproductive isolation during temperature adaptation showcases incipient ecological speciation. The potential evidence of postmating reproductive isolation among replicates gave rise to two hypotheses: (1) mutation-order speciation through a common selection on early fecundity leading to an inherent inter-locus sexual conflict; (2) system drift with genetic drift along the neutral ridges.


Asunto(s)
Calor , Aislamiento Reproductivo , Masculino , Adaptación Fisiológica/genética , Animales , Femenino , Especiación Genética , Metabolismo de los Lípidos
16.
Planta ; 238(1): 191-204, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23624978

RESUMEN

The identification, isolation and functional characterization of two genes encoding two monoterpene synthases-γ-terpinene synthase (Tctps2) and α-terpineol synthase (Tctps5)-from three chemically distinct Thymus caespititius (Lamiaceae) genotypes were performed. Genomic exon-intron structure was also determined for both terpene synthase genes, revealing an organization with seven exons and six introns. The cDNA of Tctps2 was 2,308 bp long and had an open reading frame of 1,794 bp encoding for a protein with 598 amino acids. Tctps5 was longer, mainly due to intron sequences, and presented high intraspecific variability on the plants analyzed. It encoded for a protein of 602 amino acids from an open reading frame of 1,806 bp comprising a total of 2,507 bp genomic sequence. The amino acid sequence of these two active Tctps genes shared 74 % pairwise identity, ranging between 42 and 94 % similarity with about 50 known terpene synthases of other Lamiaceae species. Gene expression revealed a multi-product Tctps2 and Tctps5 enzymes, producing γ-terpinene and α-terpineol as major components, respectively. These enzymatic results were consistent with the monoterpene profile present in T. caespititius field plants, suggesting a transcriptional regulation in leaves. Herewith reported for the first time for this species, these two newly characterized Tctps genes improve the understanding of the molecular mechanisms of reaction responsible for terpene biosynthesis and chemical diversity found in T. caespititius.


Asunto(s)
Transferasas Alquil y Aril/genética , Lamiaceae/enzimología , Lamiaceae/genética , Transferasas Alquil y Aril/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Regulación de la Expresión Génica de las Plantas , Intrones , Lamiaceae/metabolismo , Datos de Secuencia Molecular , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Homología de Secuencia de Aminoácido
17.
Am J Bot ; 100(4): 722-34, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23510759

RESUMEN

PREMISE OF THE STUDY: Anagenesis (or phyletic evolution) is one mode of speciation that occurs in the evolution of plants on oceanic islands. Of two endemic species on the Juan Fernández Islands (Chile), Myrceugenia fernandeziana and M. schulzei (Myrtaceae), believed to have originated anagenetically from different continental progenitors, the first is endemic to Robinson Crusoe Island and has no clear tie to continental relatives; the last is endemic to the younger island, Alejandro Selkirk Island, and has close affinity to M. colchaguensis in mainland Chile. METHODS: Using AFLPs and six nuclear microsatellites from 381 individuals representing 33 populations, we determined patterns of genetic variation within and among populations on both islands and between those of the islands and mainland. KEY RESULTS: Considerable genetic variation was found within populations on both islands. The level of gene diversity within M. schulzei was equivalent to that of its close continental relative M. colchaguensis. Genetic diversity was not partitioned geographically in M. fernandeziana and was weakly so and nonsignificantly in M. schulzei. CONCLUSIONS: The high genetic variation in both taxa is most likely due to anagenetic speciation. Subsidence of the older island Robinson Crusoe, landscape erosion, and restructuring of communities have severely reduced the overall island population to a single panmictic system. On the younger and less modified Alejandro Selkirk Island, slightly stronger patterns of genetic divergence are seen in M. schulzei. Because both species are genetically diverse and number in the thousands of individuals, neither is presently endangered in the archipelago.


Asunto(s)
Variación Genética , Myrtaceae/genética , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Chile , Repeticiones de Microsatélite , Filogeografía
18.
Plant Physiol Biochem ; 196: 318-327, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36738511

RESUMEN

The diversity of plant monoterpenes is largely based on the catalytic activity of monoterpene synthases. Additionally, copy number variation of monoterpene synthase genes may contribute to the quantity of transcripts and hence to the essential oil profile. This study used whole-genome sequencing and digital PCR for the measurement of copy number variation and quantification of gene expression in three closely related Salvia species, namely Salvia officinalis, Salvia pomifera and Salvia fruticosa. Twelve, 13 and 15 monoterpene synthase-encoding open-reading frames were predicted for Salvia officinalis, Salvia pomifera and Salvia fruticosa, respectively. In Salvia officinalis, one of the open reading frames was disrupted indicating a pseudogene. Monoterpene synthase genes were generally single copy per haploid genome, only a few were double or triple copy genes. Expression levels of monoterpene synthases in leaves corresponded generally well with essential oil composition. In some cases, a higher expression level of a certain monoterpene synthase could be explained by its duplication or triplication. The very high content of thujones in Salvia pomifera, for example, was accompanied by gene duplication and increased gene expression of (+)-sabinene synthase responsible for the thujone precursor sabinene. In Salvia officinalis, three individuals different in their essential oil profile showed significant differences in their monoterpene synthase expression levels corresponding roughly to the profile of the essential oils. Transcript expression of monoterpene synthase genes were measured in leaf, calyx and corolla. The corolla differed significantly from leaves, while calyces usually showed a profile intermediary between leaf and corolla.


Asunto(s)
Aceites Volátiles , Salvia officinalis , Salvia , Salvia officinalis/genética , Salvia officinalis/metabolismo , Variaciones en el Número de Copia de ADN , Monoterpenos/metabolismo , Salvia/genética , Salvia/metabolismo , Aceites Volátiles/metabolismo
19.
Am J Bot ; 99(12): e487-9, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23196393

RESUMEN

PREMISE OF THE STUDY: Microsatellite markers were developed in Erigeron rupicola and tested by amplification in six Erigeron species endemic to the Juan Fernández Archipelago, Chile, to investigate genetic diversity and population structure. • METHODS AND RESULTS: Using 454 pyrosequencing, 24 primer pairs were developed in E. rupicola, 12 of which amplified and presented polymorphism among endemic species of Erigeron in the Archipelago. Two populations from E. rupicola and E. fernandezianus were genotyped, and one to eight alleles per locus per population were detected. The expected heterozygosity ranged from 0.000 to 0.812. • CONCLUSIONS: These results indicate the utility of primers for cross-species populational studies in all endemic species of Erigeron in the Archipelago.


Asunto(s)
Cartilla de ADN/genética , ADN de Plantas/genética , Erigeron/genética , Repeticiones de Microsatélite , Polimorfismo Genético , Chile , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN
20.
Anal Biochem ; 409(1): 153-5, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-20946863

RESUMEN

Admixtures of different plant species are a common problem in raw materials for medicinal use. Two exemplary assays were developed to admixtures in Helleborus niger with high-resolution melting analysis. HRM proved to be a very sensitive tool in detecting admixtures, able to detect a ratio of 1:1000 with unknown species, and of 1:200,000 with Veratrum nigrum. The example proves the ability of HRM for quantification in multiplex PCR. The method is not limited to detecting adulterations. It can also be used to quantify a specific target by integrating a second amplicon in the assay as internal standard.


Asunto(s)
ADN de Plantas/química , Reacción en Cadena de la Polimerasa/métodos , Cartilla de ADN/química , Genotipo , Helleborus/genética , Desnaturalización de Ácido Nucleico , Espectrometría de Fluorescencia , Temperatura de Transición , Veratrum/genética
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