29 research outputs found

    AVONET: Morphological, ecological and geographical data for all birds

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    Functional traits offer a rich quantitative framework for developing and testing theories in evolutionary biology, ecology and ecosystem science. However, the potential of functional traits to drive theoretical advances and refine models of global change can only be fully realised when species-level information is complete. Here we present the AVONET dataset containing comprehensive functional trait data for all birds, including six ecological variables, 11 continuous morphological traits, and information on range size and location. Raw morphological measurements are presented from 90,020 individuals of 11,009 extant bird species sampled from 181 countries. These data are also summarised as species averages in three taxonomic formats, allowing integration with a global phylogeny, geographical range maps, IUCN Red List data and the eBird citizen science database. The AVONET dataset provides the most detailed picture of continuous trait variation for any major radiation of organisms, offering a global template for testing hypotheses and exploring the evolutionary origins, structure and functioning of biodiversity.Fil: Tobias, Joseph A.. Imperial College London; Reino Unido. University of Oxford; Reino UnidoFil: Sheard, Catherine. University of Oxford; Reino Unido. University of Bristol; Reino UnidoFil: Pigot, Alex L.. University of Oxford; Reino Unido. University College London; Estados UnidosFil: Devenish, Adam J. M.. Imperial College London; Reino UnidoFil: Yang, Jingyi. Imperial College London; Reino UnidoFil: Sayol, Ferran. University College London; Estados UnidosFil: Neate Clegg, Montague H. C.. University of Oxford; Reino Unido. University of Utah; Estados UnidosFil: Alioravainen, Nico. University of Oxford; Reino Unido. Natural Resources Institute Finland; FinlandiaFil: Weeks, Thomas L.. Imperial College London; Reino Unido. Natural History Museum; Reino UnidoFil: Barber, Robert A.. Imperial College London; Reino UnidoFil: Walkden, Patrick A.. Imperial College London; Reino Unido. Natural History Museum; Reino UnidoFil: MacGregor, Hannah E. A.. University of Oxford; Reino Unido. University of Bristol; Reino UnidoFil: Jones, Samuel E. I.. University of Oxford; Reino Unido. University of London; Reino UnidoFil: Vincent, Claire. Organización de Las Naciones Unidas; ArgentinaFil: Phillips, Anna G.. Senckenberg Biodiversity And Climate Research Centre; AlemaniaFil: Marples, Nicola M.. Trinity College; Estados UnidosFil: Montaño Centellas, Flavia A.. Universidad Mayor de San Andrés; Bolivia. University of Florida; Estados UnidosFil: Leandro Silva, Victor. Universidade Federal de Pernambuco; BrasilFil: Claramunt, Santiago. University of Toronto; Canadá. Royal Ontario Museum; CanadáFil: Darski, Bianca. Universidade Federal do Rio Grande do Sul; BrasilFil: Freeman, Benjamin G.. University of British Columbia; CanadáFil: Bregman, Tom P.. University of Oxford; Reino Unido. Future-Fit Foundation; Reino UnidoFil: Cooney, Christopher R.. University Of Sheffield; Reino UnidoFil: Hughes, Emma C.. University Of Sheffield; Reino UnidoFil: Capp, Elliot J. R.. University Of Sheffield; Reino UnidoFil: Varley, Zoë K.. University Of Sheffield; Reino Unido. Natural History Museum; Reino UnidoFil: Friedman, Nicholas R.. Okinawa Institute of Science and Technology Graduate University; JapónFil: Korntheuer, Heiko. Johannes Gutenberg Universitat Mainz; AlemaniaFil: Corrales Vargas, Andrea. Universidad Nacional de Costa Rica; Costa RicaFil: García, Natalia Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentin

    AVONET: morphological, ecological and geographical data for all birds

    Get PDF
    Functional traits offer a rich quantitative framework for developing and testing theories in evolutionary biology, ecology and ecosystem science. However, the potential of functional traits to drive theoretical advances and refine models of global change can only be fully realised when species‐level information is complete. Here we present the AVONET dataset containing comprehensive functional trait data for all birds, including six ecological variables, 11 continuous morphological traits, and information on range size and location. Raw morphological measurements are presented from 90,020 individuals of 11,009 extant bird species sampled from 181 countries. These data are also summarised as species averages in three taxonomic formats, allowing integration with a global phylogeny, geographical range maps, IUCN Red List data and the eBird citizen science database. The AVONET dataset provides the most detailed picture of continuous trait variation for any major radiation of organisms, offering a global template for testing hypotheses and exploring the evolutionary origins, structure and functioning of biodiversity

    Immortalisation of Normal Human Urothelial Cells Compromises Differentiation Capacity.

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    BACKGROUND: The development of urothelial malignancy is not solely a consequence of loss of proliferation constraints but also involves loss of cellular differentiation, defined histopathologically as grade. Although tumour grade is an independent prognostic marker for urothelial carcinoma (UC), the molecular events underpinning the loss of urothelial differentiation are poorly understood. OBJECTIVE: To examine the effect of gene alterations implicated in UC development on the ability of human urothelial cells to undergo molecular differentiation and form a functional urothelial barrier. DESIGN, SETTING, AND PARTICIPANTS: Laboratory study. INTERVENTION: Normal human urothelial (NHU) cell cultures were transduced with recombinant retroviruses to produce stable sublines overexpressing wild-type or oncogenic mutated fibroblast growth factor receptor 3 or human telomerase reverse transcriptase (hTERT). Previously generated NHU sublines carrying dominant-negative CDK4 and p53 mutant genes or immortalised with the human papillomavirus 16 E6 oncoprotein were included. MEASUREMENTS: The activity of introduced transgenes was demonstrated by comparing phenotypes of transgene-expressing and isogenic control NHU cells. Modified and control sublines were compared for changes in generational potential (life span) and capacity to respond to differentiation-inducing signals by transcript expression of uroplakins 2 and 3. The ability to form a barrier epithelium was assessed by measuring the transepithelial electrical resistance. RESULTS AND LIMITATIONS: By contrast to tumour suppressor loss of function or oncogene overactivation, hTERT overexpression alone led to life span extension and immortalisation. The hTERT immortalised cells carried no gross genomic alterations but became progressively insensitive to differentiation signals and lost the ability to form an epithelial barrier. Further characterisation of hTERT cells revealed a downregulation of p16 cyclin-dependent kinase inhibitor expression and loss of responsiveness to peroxisome proliferator-activated receptor γ, providing mechanistic explanations for the subjugation of senescence constraints and the abrogation of differentiation capability, respectively. Although immortalised urothelial cell lines without karyotypic aberrations may be generated, such cell lines are compromised in terms of differentiation and functional capacity. CONCLUSIONS: Overexpression of hTERT promotes development of an immortalised differentiation-insensitive urothelial cell phenotype. Although such cells offer a useful insight into the grade/stage paradigm of UC, they have limited value for investigating normal urothelial cell/tissue biology and physiology

    Differentiation-Associated Reprogramming of the Transforming Growth Factor β Receptor Pathway Establishes the Circuitry for Epithelial Autocrine/Paracrine Repair

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    <div><p>Transforming growth factor (TGF) β has diverse and sometimes paradoxical effects on cell proliferation and differentiation, presumably reflecting a fundamental but incompletely-understood role in regulating tissue homeostasis. It is generally considered that downstream activity is modulated at the ligand:receptor axis, but microarray analysis of proliferative versus differentiating normal human bladder epithelial cell cultures identified unexpected transcriptional changes in key components of the canonical TGFβ R/activin signalling pathway associated with cytodifferentiation. Changes included upregulation of the transcriptional modulator SMAD3 and downregulation of inhibitory modulators SMURF2 and SMAD7. Functional analysis of the signalling pathway revealed that non-differentiated normal human urothelial cells responded in paracrine mode to TGFβ by growth inhibition, and that exogenous TGFβ inhibited rather than promoted differentiation. By contrast, in differentiated cell cultures, SMAD3 was activated upon scratch-wounding and was involved in promoting tissue repair. Exogenous TGFβ enhanced the repair and resulted in hyperplastic scarring, indicating a feedback loop implicit in an autocrine pathway. Thus, the machinery for autocrine activation of the SMAD3-mediated TGFβR pathway is established during urothelial differentiation, but signalling occurs only in response to a trigger, such as wounding. Our study demonstrates that the circuitry of the TGFβR pathway is defined transcriptionally within a tissue-specific differentiation programme. The findings provide evidence for re-evaluating the role of TGFβR signalling in epithelial homeostasis as an autocrine-regulated pathway that suppresses differentiation and promotes tissue repair. This provides a new paradigm to help unravel the apparently diverse and paradoxical effect of TGFβ signalling on cell proliferation and differentiation.</p> </div

    Influence of TGFβ and TGFβ inhibitors on morphology and proliferation of NHU cell cultures.

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    <p>(a) Phase-contrast micrographs of NHU cell cultures at confluence following growth for 6 days in the presence of 0.1% DMSO, TGFβ1 (2 ng/ml) or SB431542 (3 µM). Scale bar: 250 µm. (b) MTT assay showing dose-response curves of viable biomass from non-differentiated (proliferative) NHU cells treated for 4 days with TGFβ1 and TGFβ2. Bars represent mean ± SD of six replicates. (c) NHU cells were treated with the inhibitors SB431542 (10 µM) or PD153035 (1 µM) in the presence or absence of TGFβ1 (2 ng/ml) for 4 days and viable biomass was assessed by MTT assay. Bars represent means ± SD of six replicate wells. Statistical analysis was by means of a 2-tailed t-test, *** = p<0.0001. (d) NHU cells from three independent cell lines (A, B, C) were cultured in the presence or absence of SB431542 (3 µM) for 4 days before growth was assessed by MTT assay. Bars represent means ± SD of six replicate wells.</p
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