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1.
Mol Phylogenet Evol ; 130: 104-114, 2019 01.
Article in English | MEDLINE | ID: mdl-30292693

ABSTRACT

Ambrosiinae are one of the most distinct subtribes in the Heliantheae alliance (Asteraceae), mainly due to specialization toward wind pollination. Taxa of the subtribe are principally native to the Americas, although some species have attained a cosmopolitan distribution. Members of subtribe Engelmanniinae are considered close to Ambrosiinae, due to shared morphological traits. However, the placement of Ambrosiinae within the Heliantheae alliance has not yet been corroborated by phylogenetic analyses. In the present study, we test the circumscription of subtribe Ambrosiinae and examine relationships among its genera. We used sequence information from three plastid (psbA-trnH, trnQ-rps16 and trnL-F) and two nuclear (ITS and D35) marker regions. Phylogenetic inference analyses were conducted, applying Bayesian Inference (BI) and Maximum Likelihood (ML). Subtribe Ambrosiinae is found monophyletic or nearly so in all analyses. The genera Dugesia and Rojasianthe (previously considered part of subtribe Engelmanniinae) in some cases cluster together with Ambrosiinae; these genera are clearly not part of Engelmanniinae. Within Ambrosiinae, the genera Parthenium and Parthenice occupy basal positions, whereas members of the genus Ambrosia are the most derived representatives of the subtribe. Previous subdivision of Ambrosiinae into "Iveae" (members having androgynous capitula and free achenes) and "Ambrosieae" (genera with unisexual heads and achenes enclosed in burs) is not corroborated. Results also allow consideration of relationships among species and subgeneric groups within Parthenium, Iva, and Ambrosia.


Subject(s)
Asteraceae/classification , Asteraceae/genetics , Phylogeny , Ambrosia/classification , Ambrosia/genetics , Bayes Theorem , DNA, Plant/genetics , Likelihood Functions , Phenotype , Plastids/genetics , Sequence Analysis, DNA
2.
Microsc Res Tech ; 81(11): 1275-1285, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30295385

ABSTRACT

Seed surface ultrastructure shows a wide variation among different species of the genus Allium that could potentially provide valuable characters in inferring the relationships. In order to evaluate inter- and intraspecific variation of testa microsculpturing in the leek alliance, 33 seed samples of Allium representing its two subgenera, six sections, and 23 species were studied. Seed testa surface was analyzed using both SEM and Stereomicroscopy. Minor differences in testa cell arrangement were observed between members of sect. Allium and sect. Avulsea (both of subg. Allium), but major contrasts were discerned between them and members of subg. Cepa. Significant similarity was distinguished in anticlinal walls of the members of sect. Allium and sect. Avulsea: they were variously undulated (U-, to ±Ω-like). Testa cells in members of subg. Cepa, and some of subg. Allium (sect. Caerulea, sect. Codonoprasum, and sect. Longivaginata) showed ribbed anticlinal walls suggesting a close relationship between them. The periclinal walls were concave, flat to convex with testa cells densely granulose at margins in sect. Caerulea; flat to convex, irregularly granulose-verrucose in sect. Codonoprasum; concave, densely granulose at margins and center in sect. Longivaginata; and convex, densely irregularly granulose, sometimes centrally verrucose in subg. Cepa. Irregularly polygonal cells were present in most species, but elongated polygonal cells in two species, A. iranicum and A. wendelboi (sect. Allium). We found significant micromorphological similarity in seed surface features between A. abbasii and A. fuscoviolaceum; A. esfandiarii and A. atroviolaceum; and A. longipapillatum and A. rotundum, corroborating close relationships.


Subject(s)
Seeds/ultrastructure , Shallots/classification , Iran , Microscopy, Electron, Scanning/methods , Phylogeny
3.
Planta Med ; 83(11): 946-953, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28395362

ABSTRACT

The fruits of Xanthium sibiricum have been widely used in traditional Chinese medicine for the treatment of nasal sinusitis and headaches. The genus Xanthium (cocklebur) is a taxonomically complex genus. Different taxonomic concepts have been proposed, some including several species, others lumping the different taxa in a few extremely polymorphic species. Due to the morphological similarities between species, the correct authentication of X. sibiricum is very difficult. Therefore, we established a polymerase chain reaction-restriction fragment length polymorphism method and diagnostic PCR based on nuclear internal transcribed spacer and chloroplast trnQ-rps16 barcodes to differentiate X. sibirium from related species.Results from the phylogenetic analyses based on sequence information from four marker regions (plastidal psbA-trnH and trnQ-rps16 and nuclear ITS and D35) support those taxonomic concepts accepting a reduced number of species, as four to five major clades are revealed in the phylogenetic reconstructions. X. sibiricum, together with some accessions from closely related taxa, is always supported as monophyletic, constituting a well-defined genetic entity. Allele-specific primer pairs for ITS and trnQ-rps16 were designed to amplify diagnostic products from the genomic DNA of X. sibiricum. Specific PCR in combination with digestion using the restriction enzyme MseI allowed for the identification of X. sibiricum by producing specific restriction patterns. The results demonstrate that the applied techniques provide effective and accurate authentication of X. sibiricum.


Subject(s)
Molecular Typing/methods , Xanthium/classification , DNA Barcoding, Taxonomic , DNA Primers , Genetic Markers , Phylogeny , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Xanthium/genetics
4.
Ecol Evol ; 6(21): 7809-7819, 2016 Nov.
Article in English | MEDLINE | ID: mdl-30128131

ABSTRACT

The shrubby milkwort (Polygala chamaebuxus L.) is widely distributed in the Alps, but occurs also in the lower mountain ranges of Central Europe such as the Franconian Jura or the Bohemian uplands. Populations in these regions may either originate from glacial survival or from postglacial recolonization. In this study, we analyzed 30 populations of P. chamaebuxus from the whole distribution range using AFLP (Amplified Fragment Length Polymorphism) analysis to identify glacial refugia and to illuminate the origin of P. chamaebuxus in the lower mountain ranges of Central Europe. Genetic variation and the number of rare fragments within populations were highest in populations from the central part of the distribution range, especially in the Southern Alps (from the Tessin Alps and the Prealps of Lugano to the Triglav Massiv) and in the middle part of the northern Alps. These regions may have served, in accordance with previous studies, as long-term refugia for the glacial survival of the species. The geographic pattern of genetic variation, as revealed by analysis of molecular variance, Bayesian cluster analysis and a PopGraph genetic network was, however, only weak. Instead of postglacial recolonization from only few long-term refugia, which would have resulted in deeper genetic splits within the data set, broad waves of postglacial expansion from several short-term isolated populations in the center to the actual periphery of the distribution range seem to be the scenario explaining the observed pattern of genetic variation most likely. The populations from the lower mountain ranges in Central Europe were more closely related to the populations from the southwestern and northern than from the nearby eastern Alps. Although glacial survival in the Bohemian uplands cannot fully be excluded, P. chamaebuxus seems to have immigrated postglacially from the southwestern or central-northern parts of the Alps into these regions during the expansion of the pine forests in the early Holocene.

5.
Forsch Komplementmed ; 22(5): 312-9, 2015.
Article in German | MEDLINE | ID: mdl-26565983

ABSTRACT

BACKGROUND: The use of Chinese medicinal drugs is becoming more common in Germany. However, the import from China results in aggravated quality controls and potentially jeopardized therapeutic safety. Therefore, in 1999 the Bavarian Department for Agriculture has initiated an interdisciplinary research project to cultivate and analyze important Chinese herbal plants. Currently 16 Bavarian-produced Chinese drugs are in use and distributed to patients by pharmacies. Despite a comparable quality of Bavarian pharmaceutical products, there are concerns remaining as the Bavarian medical drugs have been used for treatment purposes on patients since 2006, without their effect having been compared to the Chinese products. Therefore we performed an observational trial using a parallel group design on patients with chronic rhinosinusitis. METHODS: The duration of the trial was 4 weeks. After a 4-week follow-up, the patients were interviewed via telephone. During the trial the patients were given 2 × 50 ml of a decoction of Chinese medicinal herbs, either (a) from Bavarian controlled cultivation (Bavaria group) or (b) from Chinese production (China group). The therapeutic success was evaluated using numerical rating scales. RESULTS: In total, 64 patients completed the observational trial (31 Bavaria group, 33 China group). Both groups showed significant improvements in the main symptom scores of chronic rhinosinusitis as well as in secondary symptoms, such as the overall state of health or the tendency to catch a cold. There were no significant differences between the groups concerning the main symptoms scores. Overall the herbal decoctions had no severe side effects. CONCLUSION: This observational trial shows that Chinese herbal drugs from Bavarian cultivation are as effective as medicinal herbs imported from China, but the effects of concomitant therapies must be considered as well. The symptom score improvements during the treatment period were obvious and should stimulate further investigation on the efficacy of this herbal formula in the treatment of chronic rhinosinusitis.


Subject(s)
Drugs, Chinese Herbal/standards , Drugs, Chinese Herbal/therapeutic use , Medicine, Chinese Traditional , Sinusitis/therapy , China , Chronic Disease/therapy , Germany , Humans
6.
Ann Bot ; 114(8): 1651-63, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25274549

ABSTRACT

BACKGROUND AND AIMS: Some species of Genlisea possess ultrasmall nuclear genomes, the smallest known among angiosperms, and some have been found to have chromosomes of diminutive size, which may explain why chromosome numbers and karyotypes are not known for the majority of species of the genus. However, other members of the genus do not possess ultrasmall genomes, nor do most taxa studied in related genera of the family or order. This study therefore examined the evolution of genome sizes and chromosome numbers in Genlisea in a phylogenetic context. The correlations of genome size with chromosome number and size, with the phylogeny of the group and with growth forms and habitats were also examined. METHODS: Nuclear genome sizes were measured from cultivated plant material for a comprehensive sampling of taxa, including nearly half of all species of Genlisea and representing all major lineages. Flow cytometric measurements were conducted in parallel in two laboratories in order to compare the consistency of different methods and controls. Chromosome counts were performed for the majority of taxa, comparing different staining techniques for the ultrasmall chromosomes. KEY RESULTS: Genome sizes of 15 taxa of Genlisea are presented and interpreted in a phylogenetic context. A high degree of congruence was found between genome size distribution and the major phylogenetic lineages. Ultrasmall genomes with 1C values of <100 Mbp were almost exclusively found in a derived lineage of South American species. The ancestral haploid chromosome number was inferred to be n = 8. Chromosome numbers in Genlisea ranged from 2n = 2x = 16 to 2n = 4x = 32. Ascendant dysploid series (2n = 36, 38) are documented for three derived taxa. The different ploidy levels corresponded to the two subgenera, but were not directly correlated to differences in genome size; the three different karyotype ranges mirrored the different sections of the genus. The smallest known plant genomes were not found in G. margaretae, as previously reported, but in G. tuberosa (1C ≈ 61 Mbp) and some strains of G. aurea (1C ≈ 64 Mbp). CONCLUSIONS: Genlisea is an ideal candidate model organism for the understanding of genome reduction as the genus includes species with both relatively large (∼1700 Mbp) and ultrasmall (∼61 Mbp) genomes. This comparative, phylogeny-based analysis of genome sizes and karyotypes in Genlisea provides essential data for selection of suitable species for comparative whole-genome analyses, as well as for further studies on both the molecular and cytogenetic basis of genome reduction in plants.


Subject(s)
Chromosomes, Plant/genetics , Evolution, Molecular , Genome Size , Genome, Plant/genetics , Magnoliopsida/genetics , Karyotyping , Magnoliopsida/growth & development , Metaphase , Photosynthesis , Phylogeny , Pollen/cytology , Staining and Labeling
7.
Mol Phylogenet Evol ; 70: 296-313, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24096055

ABSTRACT

The flora of the Mediterranean region and Macaronesia is characterized by high levels of species diversity and endemism. We examined phylogenetic relationships of Scrophularia within one of its secondary centers of diversity located in the Iberian Peninsula and adjacent Macaronesia. In total, 65 ingroup accessions from 45 species, representing an almost complete sampling of the region, were analyzed using sequences from the internal transcribed spacer region (ITS) and the plastid trnQ-rps16 intergenic spacer. Phylogenetic relationships were inferred using Bayesian inference, maximum likelihood and statistical parsimony networking. Incongruence between datasets was assessed with statistical tests and displayed by split networks. Biogeographic inferences incorporating information from both markers (despite low resolution in some parts of the trees) and all incongruent taxa were accomplished with a novel combination of methods, using trees generated with the taxon duplication approach as input for Bayesian binary MCMC (BBM) analysis as implemented in RASP. Nuclear and chloroplast markers support a clade which comprises the majority of Iberian and Macaronesian species and consists of three subclades. Analyses of the substantial incongruence observed among markers indicate reticulate evolution and suggest that Scrophularia species diversity in this region is largely attributable to hybridization; a combination of both polyploidy and dysploidy in the karyotypic evolution of Western Mediterranean Scrophularia taxa is proposed. Our results provide support for an ancient hybridization event between two widespread lineages, which resulted in an allopolyploid ancestor of the Iberian - Macaronesian group with 2n=58 chromosomes. The ancestor then diverged into the three main lineages present in the Iberian Peninsula, Northern Africa and Macaronesia today. Subsequent interspecific hybridizations at different ploidy levels additionally generated new species. Presumably, hybridization and diversification within the genus in the Western Mediterranean have not been restricted to one particular event, but occurred repeatedly. It can be assumed that the topographical complexity found in the Iberian Peninsula has promoted diversification and hybrid speciation processes in Scrophularia, and that isolation in glacial refugia has preserved recent and ancient lineages. For the Macaronesian taxa, biogeographic analyses support several origins, by colonizations from at least four distinct lineages.


Subject(s)
Biodiversity , Evolution, Molecular , Phylogeny , Scrophularia/genetics , Atlantic Ocean , Bayes Theorem , Hybridization, Genetic , Mediterranean Sea , Phylogeography , Plastids/genetics , Sequence Analysis, DNA
8.
Mol Phylogenet Evol ; 69(3): 535-51, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23916621

ABSTRACT

Although tribe Stachydeae (Lamiaceae) is considered monophyletic, relationships within the tribe are still poorly understood. The complexity of Stachydeae includes paraphyletic genera, considerable morphological plasticity, a range of ploidy levels, and presumably frequent natural hybridization. We performed parsimony and Bayesian phylogenetic analyses of nuclear (ribosomal ITS) and plastid (trnL intron, trnL-trnF spacer, rps16 intron) DNA sequence data from a taxonomically and geographically broad sampling of the tribe to identify major evolutionary lineages and to test taxonomic hypotheses within this largest of all lamioid tribes. We included 143 accessions corresponding to 121 species, representing both Old and New World species, and all 12 recognized genera of tribe Stachydeae. Both nuclear and plastid data corroborate monophyly of the tribe, with Melittis as sister to all remaining Stachydeae. For the latter well-supported clade, we suggest the phylogenetic name Eurystachys. Within Eurystachys, although monophyly is supported by both nuclear and plastid data for several named and unnamed groups, the majority of recognized taxa appear to be para- or polyphyletic. The taxon compositions of most subclades are congruent between the plastid and nuclear tree topologies, whereas their relative phylogenetic placements are often not. This level of plastid-nuclear incongruence suggests considerable impact of hybridization in the evolution of Stachydeae.


Subject(s)
Evolution, Molecular , Lamiaceae/classification , Phylogeny , Bayes Theorem , Cell Nucleus/genetics , DNA, Chloroplast/genetics , DNA, Plant/genetics , DNA, Ribosomal Spacer/genetics , Hybridization, Genetic , Lamiaceae/genetics , Phylogeography , Sequence Analysis, DNA
9.
Org Lett ; 15(11): 2590-3, 2013 Jun 07.
Article in English | MEDLINE | ID: mdl-23672531

ABSTRACT

Mbandakamines A (1) and B (2), isolated from the leaves of an as yet unidentified Congolese Ancistrocladus species, are the first dimeric naphthylisoquinoline alkaloids with an unsymmetrically coupled central biaryl axis. Their novel 6',1″-coupling type implies a hitherto unprecedented peri-peri coupling in one of the naphthalene parts, leading to the as yet highest steric hindrance at the central axis and a total of seven elements of chirality. Mbandakamine A exhibits good antimalarial activity.


Subject(s)
Alkaloids/chemistry , Antimalarials/chemistry , Isoquinolines/chemistry , Naphthalenes/chemistry , Plant Extracts/chemistry , Plant Leaves/chemistry , Plasmodium falciparum/chemistry , Plasmodium falciparum/drug effects , Alkaloids/pharmacology , Antimalarials/pharmacology , Dimerization , Isoquinolines/isolation & purification , Isoquinolines/pharmacology , Magnetic Resonance Spectroscopy , Molecular Structure , Naphthalenes/isolation & purification , Naphthalenes/pharmacology , Plant Extracts/isolation & purification , Stereoisomerism
10.
J Exp Bot ; 62(13): 4639-47, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21633084

ABSTRACT

Carnivory in plants is an adaptation strategy to nutrient-poor environments and soils. Carnivorous plants obtain some additional mineral nutrients by trapping and digesting prey; the genus Nepenthes is helped by its specialized pitcher traps. To make the nutrients available, the caught prey needs to be digested, a process that requires the concerted activity of several hydrolytic enzymes. To identify and investigate the various enzymes involved in this process, fluid from Nepenthes traps has been analysed in detail. In this study, a novel type of Nepenthes endochitinase was identified in the digestion fluid of closed pitchers. The encoding endochitinase genes have been cloned from eight different Nepenthes species. Among these, the deduced amino acid sequence similarity was at least 94.9%. The corresponding cDNA from N. rafflesiana was heterologously expressed, and the purified protein, NrChit1, was biochemically characterized. The enzyme, classified as a class III acid endochitinase belonging to family 18 of the glycoside hydrolases, is secreted into the pitcher fluid very probably due to the presence of an N-terminal signal peptide. Transcriptome analyses using real-time PCR indicated that the presence of prey in the pitcher up-regulates the endochitinase gene not only in the glands, which are responsible for enzyme secretion, but at an even higher level, in the glands' surrounding tissue. These results suggest that in the pitchers' tissues, the endochitinase as well as other proteins from the pitcher fluid might fulfil a different, primary function as pathogenesis-related proteins.


Subject(s)
Carnivory/physiology , Chitinases/metabolism , Plant Proteins/metabolism , Sarraceniaceae/anatomy & histology , Sarraceniaceae/enzymology , Amino Acid Sequence , Chitinases/chemistry , Chitinases/genetics , Cloning, Molecular , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Plant , Models, Molecular , Molecular Sequence Data , Phylogeny , Plant Proteins/chemistry , Plant Proteins/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Real-Time Polymerase Chain Reaction
11.
Planta Med ; 76(17): 1956-62, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21077027

ABSTRACT

Chinese herbal medicine (CHM) is increasingly used in Germany and Europe. Due to the need for herbal drugs of consistent quality and reliable supply, methods for commercial field cultivation and post-harvest processing under south German conditions have been developed for selected plant species used in CHM since 1999. The project used an interdisciplinary approach covering all aspects from seed sourcing to medicinal application. This paper describes the outcome of the agricultural seed and field experiments, breeding program, botanical and chemical characterization of the experimental material, comparison of experimental and imported herbal material with respect to their pharmaceutical quality, transfer of production methods and plant material to specialized farmers, medicinal application and, finally, information for users along the chain of distribution about the benefits of the locally produced herbal material.


Subject(s)
Agriculture , Breeding , Plants, Medicinal/chemistry , Plants, Medicinal/genetics , DNA, Plant/analysis , Drugs, Chinese Herbal/chemistry , Europe , Germany , Seeds/classification , Sequence Analysis, DNA
12.
BMC Evol Biol ; 10: 352, 2010 Nov 12.
Article in English | MEDLINE | ID: mdl-21073690

ABSTRACT

BACKGROUND: In the large angiosperm order Lamiales, a diverse array of highly specialized life strategies such as carnivory, parasitism, epiphytism, and desiccation tolerance occur, and some lineages possess drastically accelerated DNA substitutional rates or miniaturized genomes. However, understanding the evolution of these phenomena in the order, and clarifying borders of and relationships among lamialean families, has been hindered by largely unresolved trees in the past. RESULTS: Our analysis of the rapidly evolving trnK/matK, trnL-F and rps16 chloroplast regions enabled us to infer more precise phylogenetic hypotheses for the Lamiales. Relationships among the nine first-branching families in the Lamiales tree are now resolved with very strong support. Subsequent to Plocospermataceae, a clade consisting of Carlemanniaceae plus Oleaceae branches, followed by Tetrachondraceae and a newly inferred clade composed of Gesneriaceae plus Calceolariaceae, which is also supported by morphological characters. Plantaginaceae (incl. Gratioleae) and Scrophulariaceae are well separated in the backbone grade; Lamiaceae and Verbenaceae appear in distant clades, while the recently described Linderniaceae are confirmed to be monophyletic and in an isolated position. CONCLUSIONS: Confidence about deep nodes of the Lamiales tree is an important step towards understanding the evolutionary diversification of a major clade of flowering plants. The degree of resolution obtained here now provides a first opportunity to discuss the evolution of morphological and biochemical traits in Lamiales. The multiple independent evolution of the carnivorous syndrome, once in Lentibulariaceae and a second time in Byblidaceae, is strongly supported by all analyses and topological tests. The evolution of selected morphological characters such as flower symmetry is discussed. The addition of further sequence data from introns and spacers holds promise to eventually obtain a fully resolved plastid tree of Lamiales.


Subject(s)
Chloroplasts/genetics , Magnoliopsida/classification , Magnoliopsida/genetics , Phylogeny , DNA, Plant/genetics , Evolution, Molecular
13.
Planta Med ; 76(17): 1963-74, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21058240

ABSTRACT

DNA technology provides a powerful tool to complement chemical analyses for authentication of Chinese medicinal plants and to ensure that herbal materials are not contaminated with ineffective or potentially harmful substitutes or adulterants. In the last two decades molecular biotechnology has provided sophisticated molecular techniques for authentication of botanical materials at the DNA level. This review provides an account of the most commonly used DNA-based technologies (RAPD, RFLP, ARMS, CAPS, AFLP, DAF, ISSR, SSR, sequencing, hybridization and microarrays) including suitable examples of Chinese medical plants. A critical evaluation of all methods is presented concerning sensitivity, reliability, reproducibility, and running costs. Recent achievements in the field of DNA barcoding and DNA chip technology that offer great potentials for screening of DNA and emerging new developments for future identification of species are briefly outlined.


Subject(s)
Genetic Techniques , Plants, Medicinal/classification , Plants, Medicinal/genetics , Amplified Fragment Length Polymorphism Analysis/methods , DNA Fingerprinting , DNA, Plant/analysis , Microsatellite Repeats , Nucleic Acid Hybridization/methods , Oligonucleotide Array Sequence Analysis/methods , Polymerase Chain Reaction/methods , Polymorphism, Restriction Fragment Length , Random Amplified Polymorphic DNA Technique/methods , Sequence Analysis, DNA
14.
Mol Phylogenet Evol ; 56(2): 768-83, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20226867

ABSTRACT

The carnivorous plant genus Genlisea A. St.-Hil. (Lentibulariaceae) comprises at least 22 species distributed in South and Central America as well as in Africa (including Madagascar). It has only recently been shown to be a true carnivore, specialized in protozoa and other small soil organisms. Here we present a statistically highly supported phylogeny of Genlisea based on three chloroplast loci. The most recent common ancestor of Genlisea most likely was of Neotropical origin and characterized by pedicels that are recurved in fruit, a strongly glandular inflorescence, and bivalvate capsule dehiscence. The further evolution of various morphological characters during the diversification of the genus is discussed. The two previously suggested subgenera Tayloria and Genlisea correspond to the two major clades found in our analyses. In subgenus Genlisea, three clades can be clearly distinguished based on molecular and morphological characters and on biogeographic patterns, which led us to propose a new sectional classification.


Subject(s)
Evolution, Molecular , Magnoliopsida/genetics , Phylogeny , DNA, Chloroplast/genetics , DNA, Plant/genetics , Geography , Magnoliopsida/classification , Sequence Alignment , Sequence Analysis, DNA
15.
Mol Phylogenet Evol ; 55(2): 501-23, 2010 May.
Article in English | MEDLINE | ID: mdl-20152913

ABSTRACT

Although the subfamily Nepetoideae (Lamiaceae) is considered to be monophyletic, relationships between tribes, subtribes and genera within the subfamily are poorly understood as complex and possibly homoplasious morphological characters make taxa difficult to delimit. DNA sequence data from three regions (chloroplast: trnK intron; trnL-F; nuclear: ITS) in total including 278 accessions, representing 38 out of 40 genera of subtribe Menthinae and 11 outgroup genera, were used to reconstruct the evolutionary history, test previous hypotheses of classification, explain biogeographic patterns and elucidate character evolution. Using maximum parsimony (MP) and Bayesian analysis phylogenetic reconstructions based on nuclear and chloroplast sequence data were incongruent, consequently the data were analyzed separately. Both nuclear and chloroplast datasets provide strong support for three major lineages: the "Satureja", "Micromeria" and "Clinopodium" group. The first contains members of Satureja and Gontscharovia. In the second lineage Micromeria s.str. and Origanum were resolved as monophyletic, Pentapleura and Zataria indicated as sister groups. Thymbra includes two species of Satureja turning the latter genus polyphyletic. Thymus is revealed as paraphyletic with respect to Argantoniella and Saccocalyx in both and Origanum in the plastid dataset only. In the third lineage, the Clinopodium-group, branching pattern is highly incongruent among datasets and possibly influenced by recent and ancient hybridization, chloroplast capture and incomplete lineage sorting. However, identical terminal groups are inferred in both analyses. A Madagascan lineage of "Micromeria", sister to the recently described South African Killickia, is suggested to represent a new genus. The Himalayan Clinopodium nepalense group and the tropical African C. abyssinicum alliance are monophyletic but indicated in different positions. Both groups appear in the ITS phylogeny in a clade with Cyclotrichium and Mentha, relationships not suggested previously. The enigmatic Micromeria cymuligera is close to Mentha and possibly is a representative of this genus. Species of Acinos, now regarded as part of Clinopodium, are mixed up with species of Ziziphora, questioning either the inclusion of Acinos in Clinopodium or generic distinctness of Ziziphora. All data sets suggest a monophyly of the New World taxa and argue for long distance dispersal from the Old World, rather than a vicariance explanation. Bystropogon marks the split up between the two lineages. Inclusion of 22 genera intermixed with Clinopodium spp. in the New World clade provides evidence that the current circumscription of the genus is highly unnatural. Low sequence divergence resulting in low phylogenetic resolution especially at the base of the clade indicate a rapid radiation accompanied by considerable ecological diversification and speciation.


Subject(s)
Evolution, Molecular , Lamiaceae/genetics , Phylogeny , Bayes Theorem , Cell Nucleus/genetics , DNA, Chloroplast/genetics , DNA, Plant/genetics , Geography , Introns , Lamiaceae/classification , Sequence Alignment , Sequence Analysis, DNA
16.
Phytochemistry ; 69(4): 1065-75, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18054973

ABSTRACT

From the roots of a recently discovered Ancistrocladus taxon, with close affinities to Ancistrocladus congolensis regarding molecular ITS sequence data, six naphthylisoquinoline alkaloids, 5'-O-demethylhamatine (2), 5'-O-demethylhamatinine (3), 6-O-demethylancistroealaine A (4), 6,5'-O,O-didemethylancistroealaine A (5), 5-epi-6-O-methylancistrobertsonine A (6), and 5-epi-4'-O-demethylancistrobertsonine C (7), have been isolated, along with a likewise benzopyranone carboxylic acid, 8. The structural elucidation succeeded by chemical, spectroscopic, and chiroptical methods. Their bioactivities were tested against protozoan parasites causing severe tropical diseases. Furthermore, eight known related alkaloids were identified.


Subject(s)
Alkaloids/chemistry , Benzofurans/chemistry , Magnoliopsida/chemistry , Alkaloids/isolation & purification , Alkaloids/pharmacology , Animals , Antiprotozoal Agents/chemistry , Antiprotozoal Agents/isolation & purification , Antiprotozoal Agents/pharmacology , Benzofurans/isolation & purification , Benzofurans/pharmacology , Leishmania donovani/drug effects , Molecular Structure , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Plant Roots/chemistry , Plasmodium falciparum/drug effects , Trypanosoma cruzi/drug effects
18.
Mol Phylogenet Evol ; 44(3): 1105-20, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17300965

ABSTRACT

The Resedaceae, containing 6 genera and ca. 85 species, are widely distributed in the Old World, with a major center of species diversity in the Mediterranean basin. Phylogenetic analyses of ITS and plastid trnL-trnF sequences of 66 species from all genera of the Resedaceae reveal (1) monophyly of the family, in congruence with preliminary phylogenetic studies; (2) molecular support for the traditional morphological subdivision of the Resedaceae into three tribes according to ovary and placentation types, and carpel number; (3) two monophyletic genera (Caylusea, Sesamoides), and one natural group (core Reseda), which includes the remaining four genera of the family (Ochradenus, Oligomeris, Randonia, Reseda); (4) a monophyletic origin for four of the six taxonomic sections recognized within Reseda (Leucoreseda, Luteola, Glaucoreseda, Phyteuma). Our results lead us to interpret an increment of the basic chromosome number in the family from x=5 to x=6 in at least two independent instances, and a broad representation of polyploids in multiple lineages across phylogenies, including association between octoploids and alien invasion in many parts of the world. Species diversity, endemism number, phylogenetic relationships and sequence divergence in Resedaceae suggest two major centers of differentiation, one in the western Mediterranean, and the other in the eastern Mediterranean and SW Asia. Two independent colonization events to the Canary Islands from Africa are indicated for the two Canarian Reseda endemics.


Subject(s)
Resedaceae/classification , Resedaceae/genetics , Cytogenetics , DNA, Intergenic/genetics , DNA, Plant/genetics , Evolution, Molecular , Genes, Plant , Geography , Phylogeny , Resedaceae/anatomy & histology
19.
J Org Chem ; 71(25): 9348-56, 2006 Dec 08.
Article in English | MEDLINE | ID: mdl-17137361

ABSTRACT

The isolation and structural elucidation of three novel-type naphthylisoquinoline alkaloids, ancistrocladinium A and B (the latter along with its atropisomer), from a Congolese Ancistrocladus species collected in the habitat Yeteto is reported. Their structures, including all stereochemical features, were elucidated by spectroscopic, chemical, and chiroptical methods. Ancistrocladinium A and B are the first N,C-coupled naphthyldihydroisoquinoline alkaloids found in nature, i.e., with an iminium-aryl axis. Although ancistrocladinium A, which is N,8'-coupled, is configurationally stable at this axis, ancistrocladinum B and its rotational isomer are based on a hitherto unprecedented N,6'-coupling type, with a slow rotation about the hetero biaryl axis at room temperature; they thus occur as a 46:54 mixture of two configurationally semistable atropo-diastereomers. For the isomerization of (P)-ancistrocladinium B to its (M)-diastereomer and for the opposite direction, the Gibbs free energies of activation were determined to be DeltaG double dagger1 = 105.8 kJ mol-1 and DeltaG double dagger2 = 105.7 kJ mol-1, respectively. In addition, the compounds were shown to have promising antileishmanial activities.


Subject(s)
Caryophyllaceae/chemistry , Isoquinolines/chemistry , Chromatography, High Pressure Liquid , Circular Dichroism , Isoquinolines/isolation & purification , Magnetic Resonance Spectroscopy , Spectrometry, Mass, Electrospray Ionization
20.
Mol Phylogenet Evol ; 41(3): 566-78, 2006 Dec.
Article in English | MEDLINE | ID: mdl-16839782

ABSTRACT

The Canary Islands have been a focus for phylogeographic studies on the colonization and diversification of endemic angiosperm taxa. Based on phylogeographic patterns, both inter island colonization and adaptive radiation seem to be the driving forces for speciation in most taxa. Here, we investigated the diversification of Micromeria on the Canary Islands and Madeira at the inter- and infraspecific level using inter simple sequence repeat PCR (ISSR), the trnK-Intron and the trnT-trnL-spacer of the cpDNA and a low copy nuclear gene. The genus Micromeria (Lamiaceae, Mentheae) includes 16 species and 13 subspecies in Macaronesia. Most taxa are restricted endemics, or grow in similar ecological conditions on two islands. An exception is M. varia, a widespread species inhabits the lowland scrub on each island of the archipelago and could represent an ancestral taxon from which radiation started on the different islands. Our analyses support a split between the "eastern" islands Fuerteventura, Lanzarote and Gran Canaria and the "western" islands Tenerife, La Palma and El Hierro. The colonization of Madeira started from the western Islands, probably from Tenerife as indicated by the sequence data. We identified two lineages of Micromeria on Gomera but all other islands appear to be colonized by a single lineage, supporting adaptive radiation as the major evolutionary force for the diversification of Micromeria. We also discuss the possible role of gene flow between lineages of different Micromeria species on one island after multiple colonizations.


Subject(s)
DNA, Chloroplast/genetics , Geranyltranstransferase/genetics , Lamiaceae/genetics , Phylogeny , Adaptation, Biological , Atlantic Islands , DNA Fingerprinting/veterinary , DNA Primers/chemistry , Genetic Variation , Introns/genetics , Lamiaceae/classification , Molecular Sequence Data , Polymerase Chain Reaction/veterinary , Sequence Analysis, DNA
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