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Energetic consequences of contrasting winter migratory strategies in a sympatric Arctic seabird duet
Jérôme Fort Harald Steen Hallvard Strøm Yann Tremblay Eirik Grønningsæter Emeline Pettex Warren P. Porter David Grémillet 《Journal of avian biology》2013,44(3):255-262
At the onset of winter, warm‐blooded animals inhabiting seasonal environments may remain resident and face poorer climatic conditions, or migrate towards more favourable habitats. While the origins and evolution of migratory choices have been extensively studied, their consequences on avian energy balance and winter survival are poorly understood, especially in species difficult to observe such as seabirds. Using miniaturized geolocators, time‐depth recorders and a mechanistic model, we investigated the migratory strategies, the activity levels and the energy expenditure of the closely‐related, sympatrically breeding Brünnich's guillemots Uria lomvia and common guillemots Uria aalge from Bjørnøya, Svalbard. The two guillemot species from this region present contrasting migratory strategies and wintering quarters: Brünnich's guillemots migrate across the North Atlantic to overwinter off southeast Greenland and Faroe Islands, while common guillemots remain resident in the Barents, the Norwegian and the White Seas. Results show that both species display a marked behavioural plasticity to respond to environmental constraint, notably modulating their foraging effort and diving behaviour. Nevertheless, we provide evidence that the migratory strategy adopted by guillemots can have important consequences for their energy balance. Overall energy expenditure estimated for the non‐breeding season is relatively similar between both species, suggesting that both southward migration and high‐arctic winter residency are energetically equivalent and suitable strategies. However, we also demonstrate that the migratory strategy adopted by Brünnich's guillemots allows them to have reduced daily energy expenditures during the challenging winter period. We therefore speculate that ‘resident’ common guillemots are more vulnerable than ‘migrating’ Brünnich's guillemots to harsh winter environmental conditions. 相似文献
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Combes-Meynet E Pothier JF Moënne-Loccoz Y Prigent-Combaret C 《Molecular plant-microbe interactions : MPMI》2011,24(2):271-284
During evolution, plants have become associated with guilds of plant-growth-promoting rhizobacteria (PGPR), which raises the possibility that individual PGPR populations may have developed mechanisms to cointeract with one another on plant roots. We hypothesize that this has resulted in signaling phenomena between different types of PGPR colonizing the same roots. Here, the objective was to determine whether the Pseudomonas secondary metabolite 2,4-diacetylphloroglucinol (DAPG) can act as a signal on Azospirillum PGPR and enhance the phytostimulation effects of the latter. On roots, the DAPG-producing Pseudomonas fluorescens F113 strain but not its phl-negative mutant enhanced the phytostimulatory effect of Azospirillum brasilense Sp245-Rif on wheat. Accordingly, DAPG enhanced Sp245-Rif traits involved in root colonization (cell motility, biofilm formation, and poly-β-hydroxybutyrate production) and phytostimulation (auxin production). A differential fluorescence induction promoter-trapping approach based on flow cytometry was then used to identify Sp245-Rif genes upregulated by DAPG. DAPG enhanced expression of a wide range of Sp245-Rif genes, including genes involved in phytostimulation. Four of them (i.e., ppdC, flgE, nirK, and nifX-nifB) tended to be upregulated on roots in the presence of P. fluorescens F113 compared with its phl-negative mutant. Our results indicate that DAPG can act as a signal by which some beneficial pseudomonads may stimulate plant-beneficial activities of Azospirillum PGPR. 相似文献
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Emeline Bouffartigues Herv Leh Marielle Anger-Leroy Sylvie Rimsky Malcolm Buckle 《Nucleic acids research》2007,35(6):e39
We compared coupling approaches of SPR to LC-MS and ProteinChip™-based mass spectrometry (SELDI™) as a means of identifying proteins captured on DNA surfaces. The approach we outline has the potential to allow multiple, quantitative analysis of macromolecular interactions followed by rapid mass spectrometry identification of retained material. 相似文献
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Atomic force microscopy imaging of SWI/SNF action: mapping the nucleosome remodeling and sliding 总被引:1,自引:0,他引:1
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Montel F Fontaine E St-Jean P Castelnovo M Faivre-Moskalenko C 《Biophysical journal》2007,93(2):566-578
We propose a combined experimental (atomic force microscopy) and theoretical study of the structural and dynamical properties of nucleosomes. In contrast to biochemical approaches, this method allows us to determine simultaneously the DNA-complexed length distribution and nucleosome position in various contexts. First, we show that differences in the nucleoproteic structure observed between conventional H2A and H2A.Bbd variant nucleosomes induce quantitative changes in the length distribution of DNA-complexed with histones. Then, the sliding action of remodeling complex SWI/SNF is characterized through the evolution of the nucleosome position and wrapped DNA length mapping. Using a linear energetic model for the distribution of DNA-complexed length, we extract the net-wrapping energy of DNA onto the histone octamer and compare it to previous studies. 相似文献
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Typhaine Esteves Alexandra Durr Emeline Mundwiller José L. Loureiro Maxime Boutry Michael A. Gonzalez Julie Gauthier Khalid H. El-Hachimi Christel Depienne Marie-Paule Muriel Rafael F. Acosta Lebrigio Marion Gaussen Anne Noreau Fiorella Speziani Alexandre Dionne-Laporte Jean-François Deleuze Patrick Dion Paula Coutinho Guy A. Rouleau Stephan Zuchner Alexis Brice Giovanni Stevanin Frédéric Darios 《American journal of human genetics》2014
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Emeline Barbet-Massin Michele Felletti Robert Schneider Stefan Jehle Guillaume Communie Nicolas Martinez Malene?Ringkj?bing Jensen Rob?W.H. Ruigrok Lyndon Emsley Anne Lesage Martin Blackledge Guido Pintacuda 《Biophysical journal》2014,107(4):941-946
1H-detected solid-state nuclear magnetic resonance (NMR) experiments are recorded on both intact and trypsin-cleaved sedimented measles virus (MeV) nucleocapsids under ultra-fast magic-angle spinning. High-resolution 1H,15N-fingerprints allow probing the degree of molecular order and flexibility of individual capsid proteins, providing an exciting atomic-scale complement to electro microscopy (EM) studies of the same systems. 相似文献
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Vanbeselaere J Chang LY Harduin-Lepers A Fabre E Yamakawa N Slomianny C Biot C Khoo KH Guerardel Y 《Journal of proteome research》2012,11(4):2164-2177
The emergence of zebrafish as a model organism for human diseases was accompanied by the development of cellular model systems that extended the possibilities for in vitro manipulation and in vivo studies after cell implantation. The exploitation of zebrafish cell systems is, however, still hampered by the lack of genomic and biochemical data. Here, we lay a path toward the efficient use of ZFL, a zebrafish liver-derived cell system, as a platform for studying glycosylation. To achieve this, we established the glycomic profile of ZFL by a combination of mass spectrometry and NMR. We demonstrated that glycoproteins were substituted by highly sialylated multiantennary N-glycans, some of them comprising the unusual zebrafish epitope Galβ1-4[Neu5Ac(α2,3)]Galβ1-4[Fuc(α1,3)]GlcNAc, and core 1 multisialylated O-glycans. Similarly, these analyses established that glycolipids were dominated by sialylated gangliosides. In parallel, analyzing the expression patterns of all putative sialyl- and fucosyltransferases, we directly correlated the identified structures to the set of enzymes involved in ZFL glycome. Finally, we demonstrated that this cell system was amenable to metabolic labeling using functionalized monosaccharides that permit in vivo imaging of glycosylation processes. Altogether, glycomics, genomics, and functional studies established ZFL as a relevant cellular model for the study of glycosylation. 相似文献