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Birgitta Bremer - One of the best experts on this subject based on the ideXlab platform.
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a revised time tree of the asterids establishing a temporal framework for evolutionary studies of the coffee family Rubiaceae
PLOS ONE, 2015Co-Authors: Niklas Wikstrom, Sylvain G Razafimandimbison, Kent Kainulainen, Jenny E E Smedmark, Birgitta BremerAbstract:Divergence time analyses in the coffee family (Rubiaceae) have all relied on the same Gentianales crown group age estimate, reported by an earlier analysis of the asterids, for defining the upper age bound of the root node in their analyses. However, not only did the asterid analysis suffer from several analytical shortcomings, but the estimate itself has been used in highly inconsistent ways in these Rubiaceae analyses. Based on the original data, we here reanalyze the divergence times of the asterids using relaxed-clock models and 14 fossil-based minimum age constraints. We also expand the data set to include an additional 67 taxa from Rubiaceae sampled across all three subfamilies recognized in the family. Three analyses are conducted: a separate analysis of the asterids, which completely mirrors the original asterid analysis in terms of taxon sample and data; a separate analysis of the Gentianales, where the result from the first analysis is used for defining a secondary root calibration point; and a combined analysis where all taxa are analyzed simultaneously. Results are presented in the form of a time-calibrated phylogeny, and age estimates for asterid groups, Gentianales, and major groups of Rubiaceae are compared and discussed in relation to previously published estimates. Our updated age estimates for major groups of Rubiaceae provide a significant step forward towards the long term goal of establishing a robust temporal framework for the divergence of this biologically diverse and fascinating group of plants.
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time tree of Rubiaceae phylogeny and dating the family subfamilies and tribes
International Journal of Plant Sciences, 2009Co-Authors: Birgitta Bremer, Torsten ErikssonAbstract:Rubiaceae are one of the largest families of plants, with ∼13,000 species. In this study, we have estimated the phylogeny for 534 Rubiaceae taxa from 329 genera with up to five different chloroplast regions by Bayesian analysis. It resulted in a highly resolved tree with many strongly supported nodes. There is strong support for the three subfamilies (Cinchonoideae, Ixoroideae, Rubioideae) and most of the 44 included tribes. A scaled‐down data set of 173 Rubiaceae taxa was used with a Bayesian approach to estimate divergence times for clades classified as tribes and subfamilies. Four fossils were used as minimum age priors, one inside each subfamily and one for Rubiaceae as a whole (Faramea‐type pollen, Scyphiphora pollen, Cephalanthus pusillus fruits, and Paleorubiaceophyllum eocenicum leaves). The estimated lineage (stem) divergence time for Rubiaceae is 90.4 Ma. The estimated lineage divergence times for the subfamilies are 84.4 (86.6) Ma for Rubioideae, 73.1 Ma for Ixoroideae, and 73.1 Ma for Cinchono...
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the rondeletia complex Rubiaceae an attempt to use its rps16 and trnl f sequence data to delimit guettardeae rondeletieae and sections within rondeletia
Annals of the Missouri Botanical Garden, 2009Co-Authors: Johan H E Rova, Piero G Delprete, Birgitta BremerAbstract:In the present study, a molecular phylogeny of the Rondeletia L. complex (Rubiaceae, Rondeletieae) was constructed with the following main objectives: (1) to evaluate the sections of Rondeletia pro ...
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phylogeny inferred from morphology and dna data characterizing well supported groups in vanguerieae Rubiaceae
Botanical Journal of the Linnean Society, 2004Co-Authors: Henrik Lantz, Birgitta BremerAbstract:Phylogeny inferred from morphology and DNA data: characterizing well-supported groups in Vanguerieae (Rubiaceae)
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more characters or more taxa for a robust phylogeny case study from the coffee family Rubiaceae
Systematic Biology, 1999Co-Authors: Birgitta Bremer, Henrik Lantz, Robert K Jansen, Bengt Oxelman, Maria Backlund, Ki Joong KimAbstract:More characters or more taxa for a robust phylogeny--case study from the coffee family (Rubiaceae).
Ninghua Tan - One of the best experts on this subject based on the ideXlab platform.
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rubipodanin a the first natural n desmonomethyl Rubiaceae type cyclopeptide from rubia podantha indicating an important role of the n9 methyl group in the conformation and bioactivity
PLOS ONE, 2015Co-Authors: Zhe Wang, Guang-zhi Zeng, Ninghua Tan, Si-meng Zhao, Limei Zhao, Xiaoqiang ChenAbstract:One new cyclic hexapeptide named rubipodanin A (1), which is the first identified natural N-desmonomethyl Rubiaceae-type cyclopeptide, together with six known Rubiaceae-type cyclopeptides (2-7) were obtained using the TLC cyclopeptide protosite detection method with ninhydrin from the roots and rhizomes of Rubia podantha. The cyclopeptide structures were elucidated by extensive spectroscopic analysis, including 1D-NMR, 2D-NMR, IR, UV and MS. The solution conformation and biological activities of 1 and RA-V (4) were evaluated, and the results demonstrated that the N-9-methyl group plays a vital role in the maintenance of the conformation and bioactivity.
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antitumor cyclic hexapeptides from rubia plants history chemistry and mechanism 2005 2011
Chimia, 2011Co-Authors: Si-meng Zhao, Jun-ting Fan, Bin Kuang, He Yan, Ninghua TanAbstract:Rubiaceae-type cyclopeptides (RAs), cyclic hexapeptides from Rubia plants, have shown potential antitumor activity in vitro and in vivo. Based on the review about plant cyclopeptides (Chem. Rev., 2006, 106: 840), this mini-review will highlight new progress on the discovery, synthesis, and mechanism of RAs isolated during 2005 to 2011, covering recent work in our group.
Lena Struwe - One of the best experts on this subject based on the ideXlab platform.
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CLADISTICS AND FAMILY LEVEL CLASSIFICATION OF THE GENTIANALES
Cladistics, 1994Co-Authors: Lena Struwe, Victor A. Albert, Birgitta BremerAbstract:The most recent classification of the angiosperm order Gentianales (Thorne, 1992) includes four principal families: Apocynaceae, Gentianaceae, Loganiaceae, and Rubiaceae. Ever since Bentham (1857) the status of Loganiaceae has been questioned, and several
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PHYLOGENY OF THE Rubiaceae AND THE LOGANIACEAE: CONGRUENCE OR CONFLICT BETWEEN MORPHOLOGICAL AND MOLECULAR DATA?
American journal of botany, 1992Co-Authors: Birgitta Bremer, Lena StruweAbstract:Phylogenetic analyses of 33 genera of Rubiaceae were performed using morphological and a few chemical characters. Parsimony analysis based on 29 characters resulted in eight equally parsimonious trees, with a consistency index of 0.40 and a retention index of 0.69. These results were compared to a phylogenetic analysis of the same genera based on chloroplast DNA restriction site data. There are discrepancies between the two analyses, but if we consider groupings reflected in the present classification there is much congruency. With the exception of four genera, all the genera are positioned in the same group of taxa in the two analyses. Clades of taxa representing three of the four subfamilies (~the Antirheoideae, ~the Rubioideae, and the ~Ixoroideae) are monophyletic, while the fourth subfamily Cinchonoideae is shown to be paraphyletic. Both analyses support a widened tribe Chiococceae, including the former subtribe Portlandiinae (Condamineeae). Furthermore, in both analyses the tribe Hamelieae is placed outside the subfamily Rubioideae where it is now housed. In search for the most plausible sister group to the Rubiaceae, the genus Cinchona (Rubiaceae) was analyzed together with 13 genera of the Loganiaceae, Nerium (Apocynaceae), and Exacum (Gentianaceae). Cornus (Comaceae), Olea (Oleaceae), and these two genera together were used as outgroups. The analysis, including 25 characters, 16 taxa, and with Cornus and Olea together as an outgroup, resulted in four equally parsimonious trees, with a consistency index of 0.53 and a retention index of 0.62. The non-Loganiaceae taxa Cinchona (Rubiaceae), Nerium (Apocynaceae), and Exacum (Gentianaceae) were all found to have their closest relatives within the Loganiaceae indicating that the Loganiaceae are paraphyletic and ought to be reclassified. As a result of the morphological data the most plausible sister group to the Rubiaceae is the tribe Gelsemieae of the Loganiaceae.
Ângelo Gilberto Manzatto - One of the best experts on this subject based on the ideXlab platform.
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FITOSSOCIOLOGIA DE UMA FLORESTA DE TERRA FIRME NA AMAZÔNIA SUL-OCIDENTAL, RONDÔNIA, BRASIL
Universidade Federal do Amapá, 2017Co-Authors: Ricardo Teixeira Andrade, Susamar Pansini, Adeilza Felipe Sampaio, Maíra Silva Ribeiro, Guilherme Sampaio Cabral, Ângelo Gilberto ManzattoAbstract:Este artigo reporta a florística e fitossociologia de 30 parcelas de 1 ha em uma floresta de Terra Firme na Amazônia Sul-Ocidental, inseridos em uma grade PPBio de 25km² e considerando-se indivíduos de DAP ≥ 1cm. Foram registrados 10679 indivíduos, sendo 89,1% árvores e 10,9% palmeiras, referentes a 196 táxons, dos quais 176 foram identificados em nível específico, distribuídos em 47 famílias e 136 gêneros. Quanto ao Índice de Valor de Importância Familiar (IVIF), os maiores valores foram apresentados pelas famílias Chrysobalanaceae, Arecaceae, Fabaceae, Rubiaceae, Lecythidaceae e Burseraceae. Em termos de riqueza de espécies, as famílias mais representativas foram Fabaceae, Arecaceae, Moraceae, Rubiaceae, Melastomataceae e Urticaceae, representando 42% da riqueza local. Os índices de diversidade de Shanon-Weaver (H’ = 3,81) e de similaridade florística calculada pelo índice de Sorensen (variando de 6 a 81%) indicam que a floresta não é muito diversificada, considerando-se o bioma amazônico, mas ainda assim com alta variabilidade da composição de espécies entre as parcelas. Palavras-chave: Fitossociologia, biodiversidade, ESEC Cuniã, PPBio, Amazônia Sul-Ocidental
Manzatto, Ângelo Gilberto - One of the best experts on this subject based on the ideXlab platform.
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FITOSSOCIOLOGIA DE UMA FLORESTA DE TERRA FIRME NA AMAZÔNIA SUL-OCIDENTAL, RONDÔNIA, BRASIL
'Revista Biota Amazonia', 2017Co-Authors: Andrade, Ricardo Teixeira, Pansini Susamar, Sampaio, Adeilza Felipe, Ribeiro, Maíra Silva, Cabral, Guilherme Sampaio, Manzatto, Ângelo GilbertoAbstract:The present study reports floristic composition and phytosociology in 1ha 30 permanent plots of a Terra Firme Forest at South-Western Amazon, inserted at a PPBio’s grid, considering trees DBH ≥ 1cm. 10678 individuals were registered, 89,1% trees and 10,9% palms, belonging to 47 families and 140 genera, within 74 identified at species level. Chrysobalanaceae, Arecaceae, Fabaceae, Rubiaceae, Lecythidaceae and Burseraceae showed highest values of IVIF. Fabaceae, Arecaceae, Moraceae, Rubiaceae, Melastomataceae and Urticaceae were most representative in terms of species richness, gathering 42% of local richness. The Shannon-Wiener diversity (H’ = 3.81) and Sorensen floristic similarity (6-81%) índices suggest that the forest environment is not very diversified considering Amazon biome, although presenting high variability of species composition between plots.Keywords: Phytosociology; biodiversity; ESEC Cuniã; PPBio; Southwestern Amazon.Este artigo reporta a florística e fitossociologia de 30 parcelas de 1 ha em uma floresta de Terra Firme na Amazônia Sul-Ocidental, inseridos em uma grade PPBio de 25km² e considerando-se indivíduos de DAP ≥ 1cm. Foram registrados 10679 indivíduos, sendo 89,1% árvores e 10,9% palmeiras, referentes a 196 táxons, dos quais 176 foram identificados em nível específico, distribuídos em 47 famílias e 136 gêneros. Quanto ao Índice de Valor de Importância Familiar (IVIF), os maiores valores foram apresentados pelas famílias Chrysobalanaceae, Arecaceae, Fabaceae, Rubiaceae, Lecythidaceae e Burseraceae. Em termos de riqueza de espécies, as famílias mais representativas foram Fabaceae, Arecaceae, Moraceae, Rubiaceae, Melastomataceae e Urticaceae, representando 42% da riqueza local. Os índices de diversidade de Shanon-Weaver (H’ = 3,81) e de similaridade florística calculada pelo índice de Sorensen (variando de 6 a 81%) indicam que a floresta não é muito diversificada, considerando-se o bioma amazônico, mas ainda assim com alta variabilidade da composição de espécies entre as parcelas.Palavras-chave: Fitossociologia, biodiversidade, ESEC Cuniã, PPBio, Amazônia Sul-Ocidental.
