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91.
Callens T Galbusera P Matthysen E Durand EY Githiru M Huyghe JR Lens L 《Molecular ecology》2011,20(9):1829-1844
Habitat fragmentation can restrict geneflow, reduce neighbourhood effective population size, and increase genetic drift and inbreeding in small, isolated habitat remnants. The extent to which habitat fragmentation leads to population fragmentation, however, differs among landscapes and taxa. Commonly, researchers use information on the current status of a species to predict population effects of habitat fragmentation. Such methods, however, do not convey information on species-specific responses to fragmentation. Here, we compare levels of past population differentiation, estimated from microsatellite genotypes, with contemporary dispersal rates, estimated from multi-strata capture-recapture models, to infer changes in mobility over time in seven sympatric, forest-dependent bird species of a Kenyan cloud forest archipelago. Overall, populations of sedentary species were more strongly differentiated and clustered compared to those of vagile ones, while geographical patterning suggested an important role of landscape structure in shaping genetic variation. However, five of seven species with broadly similar levels of genetic differentiation nevertheless differed substantially in their current dispersal rates. We conclude that post-fragmentation levels of vagility, without reference to past population connectivity, may not be the best predictor of how forest fragmentation affects the life history of forest-dependent species. As effective conservation strategies often hinge on accurate prediction of shifts in ecological and genetic relationships among populations, conservation practices based solely upon current population abundances or movements may, in the long term, prove to be inadequate. 相似文献
92.
El Chartouni L Tisserant B Siah A Duyme F Leducq JB Deweer C Fichter-Roisin C Sanssené J Durand R Halama P Reignault P 《Mycologia》2011,103(4):764-774
Mycosphaerella graminicola populations were examined in France with microsatellite markers and PCR-SSCP analysis of partial actin and β-tubulin encoding sequences. A total of 363 isolates was sampled in 2005 from 17 provinces, and genotypes from corresponding strains were characterized. Unique haplotypes comprised 84% of the population, and gene diversity was high nationwide (0.70) and locally. A moderate genetic differentiation (G(ST) = 0.18) was found and indicated that in France the M. graminicola population was more structured than in other previously studied European countries. Bayesian structure analysis identified three genetic clusters distributed among the 17 provinces. Our results highlighted the potential for the adaptation of the fungus to local conditions, leading to genetic clusters among the French population of the fungus as well as genotype flow between regional clusters. 相似文献
93.
Christine P. Diggle Daniel J. Moore Girish Mali Petra zur Lage Aouatef Ait-Lounis Miriam Schmidts Amelia Shoemark Amaya Garcia Munoz Mihail R. Halachev Philippe Gautier Patricia L. Yeyati David T. Bonthron Ian M. Carr Bruce Hayward Alexander F. Markham Jilly E. Hope Alex von Kriegsheim Hannah M. Mitchison Ian J. Jackson Bénédicte Durand Walter Reith Eamonn Sheridan Andrew P. Jarman Pleasantine Mill 《PLoS genetics》2014,10(9)
94.
André Breton Brigitte Gaillard-Martine Corinne Gerbi Béatrice Gomez de Ségura Roger Durand Belgacem Kherratia 《Current microbiology》1995,31(4):224-227
-d-Glucosidase, -d-fucosidase -d-xylosidase, and -cellobiopyranosidase activities in Caecomyces communis, Neocallimastix frontalis, and Piromyces rhizinflata, located with fluorescent conjugates, occur throughout the whole thallus as from zoospore germination and disappear before sporulation. -d-Galactosidase and -l-arabinopyranosidase activities are low or nonexistent. A xylanase, detected by indirect immunofluorescence, was observed at the surface of the vegetative cells, vesicles, or rhizoids. Cross-reactions prove the existence of analogies in structure among the enzymes of these anaerobic gut fungi. 相似文献
95.
Sébastien Tisné Yann Serrand Liên Bach Elodie Gilbault Rachid Ben Ameur Hervé Balasse Roger Voisin David Bouchez Mylène Durand‐Tardif Philippe Guerche Gaël Chareyron Jérôme Da Rugna Christine Camilleri Olivier Loudet 《The Plant journal : for cell and molecular biology》2013,74(3):534-544
Increased phenotyping accuracy and throughput are necessary to improve our understanding of quantitative variation and to be able to deconstruct complex traits such as those involved in growth responses to the environment. Still, only a few facilities are known to handle individual plants of small stature for non‐destructive, real‐time phenotype acquisition from plants grown in precisely adjusted and variable experimental conditions. Here, we describe Phenoscope, a high‐throughput phenotyping platform that has the unique feature of continuously rotating 735 individual pots over a table. It automatically adjusts watering and is equipped with a zenithal imaging system to monitor rosette size and expansion rate during the vegetative stage, with automatic image analysis allowing manual correction. When applied to Arabidopsis thaliana, we show that rotating the pots strongly reduced micro‐environmental disparity: heterogeneity in evaporation was cut by a factor of 2.5 and the number of replicates needed to detect a specific mild genotypic effect was reduced by a factor of 3. In addition, by controlling a large proportion of the micro‐environmental variance, other tangible sources of variance become noticeable. Overall, Phenoscope makes it possible to perform large‐scale experiments that would not be possible or reproducible by hand. When applied to a typical quantitative trait loci (QTL) mapping experiment, we show that mapping power is more limited by genetic complexity than phenotyping accuracy. This will help to draw a more general picture as to how genetic diversity shapes phenotypic variation. 相似文献
96.
Genetic variants in LEP,LEPR, and MC4R explain 30% of severe obesity in children from a consanguineous population 下载免费PDF全文
97.
Olivier Duron Valérie No?l Karen D. McCoy Matteo Bonazzi Karim Sidi-Boumedine Olivier Morel Fabrice Vavre Lionel Zenner Elsa Jourdain Patrick Durand Céline Arnathau Fran?ois Renaud Jean-Fran?ois Trape Abel S. Biguezoton Julie Cremaschi Muriel Dietrich Elsa Léger Ana?s Appelgren Marlène Dupraz Elena Gómez-Díaz Georges Diatta Guiguigbaza-Kossigan Dayo Hassane Adakal Sébastien Zoungrana Laurence Vial Christine Chevillon 《PLoS pathogens》2015,11(5)
Q fever is a highly infectious disease with a worldwide distribution. Its causative agent, the intracellular bacterium Coxiella burnetii, infects a variety of vertebrate species, including humans. Its evolutionary origin remains almost entirely unknown and uncertainty persists regarding the identity and lifestyle of its ancestors. A few tick species were recently found to harbor maternally-inherited Coxiella-like organisms engaged in symbiotic interactions, but their relationships to the Q fever pathogen remain unclear. Here, we extensively sampled ticks, identifying new and atypical Coxiella strains from 40 of 58 examined species, and used this data to infer the evolutionary processes leading to the emergence of C. burnetii. Phylogenetic analyses of multi-locus typing and whole-genome sequencing data revealed that Coxiella-like organisms represent an ancient and monophyletic group allied to ticks. Remarkably, all known C. burnetii strains originate within this group and are the descendants of a Coxiella-like progenitor hosted by ticks. Using both colony-reared and field-collected gravid females, we further establish the presence of highly efficient maternal transmission of these Coxiella-like organisms in four examined tick species, a pattern coherent with an endosymbiotic lifestyle. Our laboratory culture assays also showed that these Coxiella-like organisms were not amenable to culture in the vertebrate cell environment, suggesting different metabolic requirements compared to C. burnetii. Altogether, this corpus of data demonstrates that C. burnetii recently evolved from an inherited symbiont of ticks which succeeded in infecting vertebrate cells, likely by the acquisition of novel virulence factors. 相似文献
98.
Local control of the host immune response performed with mesenchymal stem cells: perspectives for functional intracerebral xenotransplantation 下载免费PDF全文
Véronique Nerrière‐Daguin Reynald Thinard Laetitia Kermarrec Tony Durand Thomas Haudebourg Bernard Vanhove Laurent Lescaudron Philippe Naveilhan 《Journal of cellular and molecular medicine》2015,19(1):124-134
Foetal pig neuroblasts are interesting candidates as a cell source for transplantation, but xenotransplantation in the brain requires the development of adapted immunosuppressive treatments. As systemic administration of high doses of cyclosporine A has side effects and does not protect xenotransplants forever, we focused our work on local control of the host immune responses. We studied the advantage of cotransplanting syngenic mesenchymal stem cells (MSC) with porcine neuroblasts (pNb) in immunocompetent rat striata. Two groups of animals were transplanted, either with pNb alone or with both MSC and pNb. At day 63, no porcine neurons were detected in the striata that received only pNb, while four of six rats transplanted with both pNb and MSC exhibited healthy porcine neurons. Interestingly, 50% of the cotransplanted rats displayed healthy grafts with pNF70+ and TH+ neurons at 120 days post‐transplantation. qPCR analyses revealed a general dwindling of pro‐ and anti‐inflammatory cytokines in the striata that received the cotransplants. Motor recovery was also observed following the transplantation of pNb and MSC in a rat model of Parkinson's disease. Taken together, the present data indicate that the immunosuppressive properties of MSC are of great interest for the long‐term survival of xenogeneic neurons in the brain. 相似文献
99.
100.
Hong Zhu Hee Yun Suk Raymond Y. L. Yu Deborah Brancho Opeyemi Olabisi Teddy T. C. Yang XiaoYong Yang Jialin Zhang Mustapha Moussaif Jorge L. Durand Linda A. Jelicks Ja-Young Kim Philipp E. Scherer Philippe G. Frank Michael P. Lisanti John W. Calvert Mark R. Duranski David J. Lefer Elaine Huston George S. Baillie Miles D. Houslay Jeffrey D. Molkentin Jianping Jin Chi-Wing Chow 《Molecular and cellular biology》2010,30(18):4379-4390