54 research outputs found
Astrocytes modify migration of pbmcs induced by β-amyloid in a blood-brain barrier in vitro model
Inhibition of PI3K Prevents the Proliferation and Differentiation of Human Lung Fibroblasts into Myofibroblasts: The Role of Class I P110 Isoforms
Idiopathic pulmonary fibrosis (IPF) is a progressive fibroproliferative disease characterized by an accumulation of fibroblasts and myofibroblasts in the alveolar wall. Even though the pathogenesis of this fatal disorder remains unclear, transforming growth factor-β (TGF-β)-induced differentiation and proliferation of myofibroblasts is recognized as a primary event. The molecular pathways involved in TGF-β signalling are generally Smad-dependent yet Smad-independent pathways, including phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt), have been recently proposed. In this research we established ex-vivo cultures of human lung fibroblasts and we investigated the role of the PI3K/Akt pathway in two critical stages of the fibrotic process induced by TGF-β: fibroblast proliferation and differentiation into myofibroblasts. Here we show that the pan-inhibitor of PI3Ks LY294002 is able to abrogate the TGF-β-induced increase in cell proliferation, in ι- smooth muscle actin expression and in collagen production besides inhibiting Akt phosphorylation, thus demonstrating the centrality of the PI3K/Akt pathway in lung fibroblast proliferation and differentiation. Moreover, for the first time we show that PI3K p110δ and p110γ are functionally expressed in human lung fibroblasts, in addition to the ubiquitously expressed p110ι and β. Finally, results obtained with both selective inhibitors and gene knocking-down experiments demonstrate a major role of p110γ and p110ι in both TGF-β-induced fibroblast proliferation and differentiation. This finding suggests that specific PI3K isoforms can be pharmacological targets in IPF
Mega-evolutionary dynamics of the adaptive radiation of birds
The origin and expansion of biological diversity is regulated by both developmental trajectories and limits on available ecological niches. As lineages diversify, an early and often rapid phase of species and trait proliferation gives way to evolutionary slow- downs as new species pack into ever more densely occupied regions of ecological niche space. Small clades such as Darwinâs finches demonstrate that natural selection is the driving force of adaptive radiations, but how microevolutionary processes scale up to shape the expansion of phenotypic diversity over much longer evolutionary timescales is unclear. Here we address this problem on a global scale by analysing a crowd-sourced dataset of three-dimensional scanned bill morphology from more than 2,000 species. We find that bill diversity expanded early in extant avian evolutionary history, before transitioning to a phase dominated by packing of morphological space. However, this early phenotypic diversification is decoupled from temporal variation in evolutionary rate: rates of bill evolution vary among lineages but are comparatively stable through time. We find that rare, but major, discontinuities in phenotype emerge from rapid increases in rate along single branches, sometimes leading to depauperate clades with unusual bill morphologies. Despite these jumps between groups, the major axes of within-group bill-shape evolution are remarkably consistent across birds. We reveal that macroevolutionary processes underlying global-scale adaptive radiations support Darwinian and Simpsonian ideas of microevolution within adaptive zones and accelerated evolution between distinct adaptive peaks
Anyone with a Long-Face? Craniofacial Evolutionary Allometry (CREA) in a Family of Short-Faced Mammals, the Felidae
Among adults of closely related species, a trend in craniofacial evolutionary allometry (CREA) for larger taxa to be long-faced and smaller ones to have paedomorphic aspects, such as proportionally smaller snouts and larger braincases, has been demonstrated in some mammals and two bird lineages. Nevertheless, whether this may represent a âruleâ with few exceptions is still an open question. In this context, Felidae is a particularly interesting family to study because, although its members are short-faced, previous research did suggest relative facial elongation in larger living representatives. Using geometric morphometrics, based on two sets of anatomical landmarks, and traditional morphometrics, for comparing relative lengths of the palate and basicranium, we performed a series of standard and comparative allometric regressions in the Felidae and its two subfamilies. All analyses consistently supported the CREA pattern, with only one minor exception in the geometric morphometric analysis of Pantherinae: the genus Neofelis. With its unusually long canines, Neofelis species seem to have a relatively narrow cranium and long face, despite being smaller than other big cats. In spite of this, overall, our findings strengthen the possibility that the CREA pattern might indeed be a âruleâ among mammals, raising questions on the processes behind it and suggesting future directions for its study
Atlantic-Mediterranean and within-Mediterranean molecular variation in Coris julis (L. 1758) (Teleostei, Labridae)
Sequence variation in the mitochondrial control region was studied in the Mediterranean rainbow wrasse (Coris julis), a species with pronounced pelagic larval phase inhabiting the Mediterranean Sea and the adjacent coastal eastern Atlantic Ocean. A total of 309 specimens from 19 sampling sites were analysed with the aim of elucidating patterns of molecular variation between the Atlantic and the Mediterranean as well as within the Mediterranean Sea. Phylogeographic analyses revealed a pronounced structuring into a Mediterranean and an Atlantic group. Samples from a site at the Moroccan Mediterranean coast in the Alboran Sea showed intermediate frequencies of âMediterraneanâ and âAtlanticâ haplotypes. We recognised a departure from molecular neutrality and a star-like genealogy for samples from the Mediterranean Sea, which we propose to have happened due to a recent demographic expansion. The results are discussed in the light of previous studies on molecular variation in fish species between the Atlantic and the Mediterranean and within the Mediterranean
Morphology of scale lepidonts in the genusAphanius(Teleostei, Cyprinodontidae) using SEM
The microstructure of the anterior region of the scales in several species of the genus Aphanius was studied by SEM with the aim of determining whether scale morphology could be used to discriminate between the species of this genus. The characters examined concern the morphology of lepidonts, or âscaleâteethâ, their distribution and mode of implantation on the circuli. These characters were also subjected to UPGMA cluster analysis. Results from phenetic analysis of scaleâteeth characters agree overall with those of previously published morphological and biogeographical studies and in part with molecular analysis of the phylogenetic relationships between species of Aphanius. An affinity between A. danfordii and A. mento (found previously in studies based on osteological observations) was seen. The separation of A. apodus from the other species of the fasciatus group, which had also been noticed from molecular observations, was also observed, as well as the affinity of A. ginaonis with the group of A. dispar+A. sirhani. This study demonstrates that scale morphology can provide useful information on the relationships among species of the genus Aphanius encouraging the use of scale characters, combined with other traits, in phylogenetic analyses
Fasta files of RNA-seq contigs generated from A_alluaudi LPJs
This file contains .fasta files, generated through assembly of RNA-seq transcripts, derived from A. alluaudi specimens used in our study. These .fasta files were used for differential expression (DE) analyses and BLAST queries, the results of which are depicted in Figure 5 and Tables S5. In tables S6 and S7, these .fasta sequences were used as queries against the human genome, and significant hits were then used for relative enrichment analyses in DAVID
Candidate gene expression using qRT-PCR on A_alluaudi LPJs
This file contains the relative expression values of candidate genes, amplifying cDNA from lower pharyngeal jaws (LPJ) of the A. alluaudi specimens. The reported values have been scaled against normalisation factors (NF) that were calculated from 2 housekeeeping genes. These expression values were subjected to statistical analyses that are reported in Figure 4 a-c and Table S4. Specimen names correspond those assigned in Table S1
Data from: Shaping development through mechanical strain: the transcriptional basis of diet-induced phenotypic plasticity in a cichlid fish
Adaptive phenotypic plasticity, the ability of an organism to change its phenotype to match local environments, is increasingly recognized for its contribution to evolution. However, few empirical studies have explored the molecular basis of plastic traits. The East African cichlid fish Astatoreochromis alluaudi displays adaptive phenotypic plasticity in its pharyngeal jaw apparatus, a structure that is widely seen as an evolutionary key innovation that has contributed to the remarkable diversity of cichlid fishes. It has previously been shown that in response to different diets, the pharyngeal jaws change their size, shape and dentition: hard diets induce an adaptive robust molariform tooth phenotype with short jaws and strong internal bone structures, while soft diets induce a gracile papilliform tooth phenotype with elongated jaws and slender internal bone structures. To gain insight into the molecular underpinnings of these adaptations and enable future investigations of the role that phenotypic plasticity plays during the formation of adaptive radiations, the transcriptomes of the two divergent jaw phenotypes were examined. Our study identified a total of 187 genes whose expression differs in response to hard and soft diets, including immediate early genes, extracellular matrix genes and inflammatory factors. Transcriptome results are interpreted in light of expression of candidate genesâmarkers for tooth size and shape, bone cells and mechanically sensitive pathways. This study opens up new avenues of research at new levels of biological organization into the roles of phenotypic plasticity during speciation and radiation of cichlid fishes
dataset_traditional morphometric
Dataset including all traditional morphometric measures and ratios used for methods 1-3. The four residuals were used for method 3. The length measures were obtained from two wing pictures of the same individual and therefore the averaged measures are shown in the dataset. Similarly for calculating the ratios averaged length and area measures (not included in the dataset) were taken from two wing pictures per individual. Because the measurement error was low we only took measurements from one wing picture for individuals from 2014
- âŚ