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1.
PLoS One ; 15(10): e0240121, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33017445

RESUMO

Worldwide, the genus Ranunculus includes approximately 600 species and is highly genetically diverse. Recent taxonomic reports suggest that the genus has a monophyletic origin, divided into two subgenera, and consists of 17 sections. The Central Asian country of Kazakhstan has 62 species of the genus that have primarily been collected in the central part of the country. The latest collection trips in southern parts of the country have led to the description of a wider distribution area for Ranunculus and the identification of a new species Ranunculus talassicus Schegol. et A.L. Ebel from Western Tien Shan. Therefore, in this study, attempts were made to assess the molecular taxonomic positions of R. talassicus and two other species endemic to the Central Asian region R. karkaralensis Schegol. and R. pskemensis V.N. Pavlov in relation to other species of the genus, using internal transcribed spacer (ITS) molecular genetic markers. The ITS-aligned sequences of 22 local Central Asian accessions and 43 accession sequences available in the National Center for Biotechnology Information (NCBI) database allowed the construction of a maximum parsimony phylogenetic tree and a Neighbor-Net network. The results indicated that R. talassicus and R. pskemensis could be assigned to section Ranunculastrum. Additionally, an assessment of the network suggested that R. pskemensis was the rooting taxon for the group of species containing R. talassicus, and that R. illyricus L. and R. pedatus Waldst. & Kit. were founders of a prime rooting node for the Ranunculastrum section of the genus. The ITS-aligned sequences showed that R. karkaralensis was indifferent with respect to three other species in the Ranunculus section of the genus, i.e., R. acris L., R. grandifolius C.A. Mey., and R. subborealis Tzvelev. The study indicated that the assessments of ITS-based phylogenetic tree and Neighbor-Net network provided new insights into the taxonomic positions of three endemic species from Central Asia.


Assuntos
DNA de Plantas/genética , Ranunculus/genética , Ásia Central , Variação Genética , Filogenia , Ranunculus/classificação
2.
Mol Ecol ; 29(11): 2031-2049, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32374933

RESUMO

The time frame and geographical patterns of diversification processes in European temperate-montane herbs are still not well understood. We used the sexual species of the Ranunculus auricomus complex as a model system to understand how vicariance versus dispersal processes in the context of Pleistocene climatic fluctuations have triggered speciation in temperate-montane plant species. We used target enrichment sequence data from about 600 nuclear genes and coalescent-based species tree inference methods to resolve phylogenetic relationships among the sexual taxa of the complex. We estimated absolute divergence times and, using ancestral range reconstruction, we tested if speciation was enhanced by vicariance or by dispersal processes. Phylogenetic relationships among taxa were fully resolved with some incongruence in the position of the tetraploid R. marsicus. Speciation events took place in a very short time at the end of the Mid-Pleistocene Transition (830-580 thousand years ago [ka]). A second wave of intraspecific geographical differentiation occurred at the end of the Riss glaciation or during the Eemian interglacial between 200 and 100 ka. Ancestral range reconstruction suggests a widespread European ancestor of the R. auricomus complex. Vicariance has triggered allopatric speciation in temperate-montane plant species during the climatic deterioration that occurred during the last phase of the Mid-Pleistocene Transition. Vegetation restructuring from forest into tundra could have confined these forest species into isolated glacial macro- and microrefugia. During subsequent warming periods, range expansions of these species could have been hampered by apomictic derivatives and by other congeneric competitors in the same habitat.


Assuntos
Especiação Genética , Filogenia , Ranunculus , Ecossistema , Europa (Continente) , Florestas , Geografia , Ranunculus/classificação , Ranunculus/genética
3.
Sci Rep ; 5: 10098, 2015 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-25993393

RESUMO

Adaptation to aquatic habitats is a formidable challenge for terrestrial angiosperms that has long intrigued scientists. As part of a suite of work to explore the molecular mechanism of adaptation to aquatic habitats, we here sequenced the transcriptome of the submerged aquatic plant Ranunculus bungei, and two terrestrial relatives R. cantoniensis and R. brotherusii, followed by comparative evolutionary analyses to determine candidate genes for adaption to aquatic habitats. We obtained 126,037, 140,218 and 114,753 contigs for R. bungei, R. cantoniensis and R. brotherusii respectively. Bidirectional Best Hit method and OrthoMCL method identified 11,362 and 8,174 1:1:1 orthologous genes (one ortholog is represented in each of the three species) respectively. Non-synonymous/synonymous (dN/dS) analyses were performed with a maximum likelihood method and an approximate method for the three species-pairs. In total, 14 genes of R. bungei potentially involved in the adaptive transition from terrestrial to aquatic habitats were identified. Some of the homologs to these genes in model plants are involved in vacuole protein formation, regulating 'water transport process' and 'microtubule cytoskeleton organization'. Our study opens the door to understand the molecular mechanism of plant adaptation from terrestrial to aquatic habitats.


Assuntos
Adaptação Fisiológica/genética , Ranunculus/genética , Transcriptoma , Mapeamento de Sequências Contíguas , Ecossistema , Variação Genética , Funções Verossimilhança , Filogenia , Ranunculus/classificação , Ranunculus/metabolismo , Análise de Sequência de RNA
4.
Mol Phylogenet Evol ; 58(1): 4-21, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21078403

RESUMO

Ranunculus is distributed in all continents and especially species-rich in the meridional and temperate zones. To reconstruct the biogeographical history of the genus, a molecular phylogenetic analysis of the genus based on nuclear and chloroplast DNA sequences has been carried out. Results of biogeographical analyses (DIVA, Lagrange, Mesquite) combined with molecular dating suggest multiple colonizations of all continents and disjunctions between the northern and the southern hemisphere. Dispersals between continents must have occurred via migration over land bridges, or via transoceanic long-distance dispersal, which is also inferred from island endemism. In southern Eurasia, isolation of the western Mediterranean and the Caucasus region during the Messinian was followed by range expansions and speciation in both areas. In the Pliocene and Pleistocene, radiations happened independently in the summer-dry western Mediterranean-Macaronesian and in the eastern Mediterranean-Irano-Turanian regions, with three independent shifts to alpine humid climates in the Alps and in the Himalayas. The cosmopolitan distribution of Ranunculus is caused by transoceanic and intracontinental dispersal, followed by regional adaptive radiations.


Assuntos
Filogeografia , Ranunculus/classificação , Ranunculus/fisiologia , Biodiversidade , DNA de Plantas/genética , DNA de Plantas/isolamento & purificação , Ecossistema , Evolução Molecular , Modelos Teóricos , Ranunculus/genética
5.
J Plant Res ; 120(2): 167-74, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17351831

RESUMO

Ranunculus nipponicus (Makino) Nakai is a vulnerable aquatic macrophyte in the Kinki district, which is the southernmost distribution of this species in Japan. The genetic diversity and structure within and among eleven extant populations were assessed using the inter-simple sequence repeats (ISSR) polymerase chain reaction in association with combinations of propagation pattern (clonal and/or seeds) and genotypic geographical structure. In total, 53 bands were amplified, of which 18 (34%) were polymorphic. Analysis of the ISSR bands identified 46 genotypes among 81 individuals from one stream population and 72 distinct genotypes among 147 individuals in the Kinki district. An unweighted pair group method with arithmetic mean (UPGMA) dendrogram showed some unity among upstream and downstream subpopulations within one stream and eleven populations. The Shannon index of genetic diversity was 0.109 for one stream population and 0.313 for total genetic diversity, suggesting relatively high genetic diversity. Analysis of molecular variance (AMOVA) revealed that 84.1% of the total genetic diversity occurred among populations and the remaining diversity (15.9%) occurred within populations. Significant genetic differentiation occurred among populations in the Kinki district. These results suggest that conservation of each population is important for maintaining genetic diversity of R. nipponicus in this district.


Assuntos
Ranunculus/classificação , Ranunculus/genética , DNA de Plantas/análise , DNA de Plantas/genética , Marcadores Genéticos , Variação Genética/genética , Geografia , Japão , Filogenia , Sequências Repetitivas de Ácido Nucleico/genética , Estudos de Amostragem
6.
Yeni Tip Tarihi Arastirmalari ; (12-15): 135-50, 2006.
Artigo em Turco | MEDLINE | ID: mdl-22164735

RESUMO

In Islamic tradition, the talismanic inscription "Yâ Kebîkeç- O Kabikaj" was believed to protect manuscripts against insects. Also in medicinal manuscripts there are several passages referring to Kabikaj used as a drug. In this study, the use of Kabikaj in medicinal manuscripts is investigated. As a result, Kabikaj is stated to be a species of Ranunculaceae family: Ranunculus asiaticus L.


Assuntos
Fitoterapia/história , Ranunculus , Etnobotânica/história , História Antiga , Humanos , Islamismo/história , Manuscritos Médicos como Assunto/história , Extratos Vegetais/química , Extratos Vegetais/história , Extratos Vegetais/uso terapêutico , Plantas Medicinais , Ranunculus/química , Ranunculus/classificação
7.
Mol Phylogenet Evol ; 36(2): 305-27, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15955512

RESUMO

Ranunculus is a large genus with a worldwide distribution. Phylogenetic analyses of c. 200 species of Ranunculus s.l. based on sequences of the nrITS using maximum parsimony and Bayesian inference yielded high congruence with previous cpDNA restriction site analyses, but strongly contradict previous classifications. A large core clade including Ranunculus subg. Ranunculus, subg. Batrachium, subg. Crymodes p.p., Ceratocephala, Myosurus, and Aphanostemma is separated from R. subg. Ficaria, subg. Pallasiantha, subg. Coptidium, subg. Crymodes p.p., Halerpestes, Peltocalathos, Callianthemoides, and Arcteranthis. Within the core clade, 19 clades can be described with morphological and karyological features. Several sections are not monophyletic. Parallel evolution of morphological characters in adaptation to climatic conditions may be a reason for incongruence of molecular data and morphology-based classifications. In some mountainous regions, groups of closely related species may have originated from adaptive radiation and rapid speciation. Split decomposition analysis indicated complex patterns of relationship and suggested hybridization in the apomictic R. auricomus complex, R. subg. Batrachium, and the white-flowering European alpines. The evolutionary success of the genus might be due to a combination of morphological plasticity and adaptations, hybridization and polyploidy as important factors for regional diversification, and a broad range of reproductive strategies.


Assuntos
DNA Espaçador Ribossômico/genética , Evolução Molecular , Filogenia , Ranunculus/genética , DNA de Plantas/química , DNA de Plantas/genética , Ranunculus/classificação , Análise de Sequência de DNA
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