Search results for "Phylogenetics"
showing 10 items of 777 documents
Phylogenetic analyses of endoparasitic Acanthocephala based on mitochondrial genomes suggest secondary loss of sensory organs
2012
The metazoan taxon Syndermata (Monogononta, Bdelloidea, Seisonidea, Acanthocephala) comprises species with vastly different lifestyles. The focus of this study is on the phylogeny within the syndermatan subtaxon Acanthocephala (thorny-headed worms, obligate endoparasites). In order to investigate the controversially discussed phylogenetic relationships of acanthocephalan subtaxa we have sequenced the mitochondrial (mt) genomes of Echinorhynchus truttae (Palaeacanthocephala), Paratenuisentis ambiguus (Eoacanthocephala), Macracanthorhynchus hirudinaceus (Archiacanthocephala), and Philodina citrina (Bdelloidea). In doing so, we present the largest molecular phylogenetic dataset so far for this…
Molecular phylogeny of the Notostraca
2012
Abstract We used a combined analysis of one nuclear (28S rDNA) and three mitochondrial markers (COI, 12S rDNA, 16S rDNA) to infer the molecular phylogeny of the Notostraca, represented by samples from the six continents that are inhabited by this group of branchiopod crustaceans. Our results confirm the monophyly of both extant notostracan genera Triops and Lepidurus with good support in model based and maximum parsimony analyses. We used branchiopod fossils as a calibration to infer divergence times among notostracan lineages and accounted for rate heterogeneity among lineages by applying relaxed-clock models. Our divergence date estimates indicate an initial diversification into the gener…
Evolution of metaphors: Phylogeny of oil slick cartoons in Spanish press
2014
The main purpose of this article is to analyze the evolution of a metaphor set over time. By studying cartoons about the oil slick caused by the Prestige oil tanker in 2002 on Spanish shores and the subsequent court decision in 2013, we observe a progressive metaphor diversification and evolution, with the oil slick as an old common trait. Additionally, using basic cladistical methods, we propose a phylogenetic tree for the metaphor set, from a common ancestor to the subsequent diversification regarding news content. These results show that phylogenetic models can be very helpful in understanding the evolution of conceptual metaphors, and this method of analysis could even be a methodologi…
Molecular phylogeny of the extinct cave lion Panthera leo spelaea.
2004
To reconstruct the phylogenetic position of the extinct cave lion (Panthera leo spelaea), we sequenced 1 kb of the mitochondrial cytochrome b gene from two Pleistocene cave lion DNA samples (47 and 32 ky B.P.). Phylogenetic analysis shows that the ancient sequences form a clade that is most closely related to the extant lions from Africa and Asia; at the same time, cave lions appear to be highly distinct from their living relatives. Our data show that these cave lion sequences represent lineages that were isolated from lions in Africa and Asia since their dispersal over Europe about 600 ky B.P., as they are not found among our sample of extant populations. The cave lion lineages presented h…
A member of the Tlr family is involved in dsRNA innate immune response in Paracentrotus lividus sea urchin
2015
Abstract The innate immune response involves proteins such as the membrane receptors of the Toll-like family (TLRs), which trigger different intracellular signalling pathways that are dependent on specific stimulating molecules. In sea urchins, TLR proteins are encoded by members of a large multigenic family composed of 60–250 genes in different species. Here, we report a newly identified mRNA sequence encoding a TLR protein (referred to as Pl-Tlr) isolated from Paracentrotus lividus immune cells. The partial protein sequence contained the conserved Toll/IL-1 receptor (TIR) domain, the transmembrane domain and part of the leucine repeats. Phylogenetic analysis of the Pl-Tlr protein was acco…
Inducible galectins are expressed in the inflamed pharynx of the ascidian Ciona intestinalis
2011
Although ascidians belong to a key group in chordate phylogenesis, amino acid sequences of Ciona intestinalis galectin-CRDs (CiLgals-a and -b) have been retained too divergent from vertebrate galectins. In the present paper, to contribute in disclosing Bi-CRD galectin evolution a novel attempt was carried out on CiLgals-a and -b CRDs phylogenetic analysis, and their involvement in ascidian inflammatory responses was shown. CiLgals resulted aligned with Bi-CRD galectins from vertebrates (Xenopus tropicalis, Gallus gallus, Mus musculus, Homo sapiens), cephalochordates (Branchiostoma floridae), echinoderms (Strongylocentrotus purpuratus) and a mono-CRD galectin from the ascidian Clavelina pict…
LPS challenge regulates gene expression and tissue localization of a Ciona intestinalis gene through an alternative polyadenylation mechanism.
2013
A subtractive hybridization strategy for the identification of differentially expressed genes was performed between LPS-challenged and naive Ciona intestinalis. This strategy allowed the characterization of two transcripts (Ci8short and Ci8long) generated by the use of two Alternative Polyadenylation sites. The Ci8long transcript contains a protein domain with relevant homology to several components of the Receptor Transporting Protein (RTP) family not present in the Ci8short mRNA. By means of Real Time PCR and Northern Blot, the Ci8short and Ci8long transcripts showed a different pattern of gene expression with the Ci8short mRNA being strongly activated after LPS injection in the pharynx. …
Asteroceras langi Dommergues & Meister, un hommage au Professeur J. Lang.
2007
4 pages; Une espèce d'ammonite du Sinémurien supérieur du Maroc, Asteroceras langi Dommergues & Meister, dédiée au professeur J. Lang est présentée à nouveau à l'occasion de ce mémoire jubilé.
Sesquiterpenoids in subtribe Centaureinae (Cass.) Dumort (tribe Cardueae, Asteraceae): distribution, (13)C NMR spectral data and biological propertie…
2012
Asteraceae Bercht. & J. Presl is one of the biggest and most economically important plant families. The taxonomy and phylogeny of Asteraceae is rather complex and according to the latest and most reliable taxonomic classification of Panero & Funk, based on the analysis of nine chloroplast regions, the family is divided into 12 subfamilies and 35 tribes. One of the largest tribes of Asteraceae is Cardueae Cass. with four subtribes (Carlininae, Echinopinae, Carduinae and Centaureinae) and more than 2500 species. Susanna & Garcia-Jacas have organized the genera of Centaureinae (about 800 species) into seven informal groups, which recent molecular studies have confirmed: 1. Basal genera; 2. Vol…
Phytochemistry and molecular systematics of Triaenophora rupestris and Oreosolen Wattii (Scrophulariaceae)
2008
The relationships between the genera Triaenophora, Oreosolen and Rehmannia were investigated. All three genera were previously included in tribe Veroniceae which was part of Scrophulariaceae but which is now included in Plantaginaceae. With regard to the content of iridoid glucosides, Triaenophora rupestris and the much-investigated Rehmannia were almost identical in containing catalpol, ajugol and 6-feruloylajugol. Oreosolen wattii was rather different in having compounds typical for the tribe Scrophularieae (Scrophulariaceae), namely aucubin, harpagide, harpagoside as well as two diesters of rhamnopyranosylcatalpol, one of which, here named oreosolenoside, had not previously been describe…