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141.
Manon Ruffin Mélanie Voland Solenne Marie Monique Bonora Elise Blanchard Sabine Blouquit-Laye Emmanuel Naline Philippe Puyo Philippe Le Rouzic Loic Guillot Harriet Corvol Annick Clement Olivier Tabary 《生物化学与生物物理学报:疾病的分子基础》2013,1832(12):2340-2351
Cystic fibrosis (CF) airway epithelium is constantly subjected to injury events due to chronic infection and inflammation. Moreover, abnormalities in CF airway epithelium repair have been described and contribute to the lung function decline seen in CF patients. In the last past years, it has been proposed that anoctamin 1 (ANO1), a Ca2 +-activated Cl? channel, might offset the CFTR deficiency but this protein has not been characterized in CF airways. Interestingly, recent evidence indicates a role for ANO1 in cell proliferation and tumor growth. Our aims were to study non-CF and CF bronchial epithelial repair and to determine whether ANO1 is involved in airway epithelial repair. Here, we showed, with human bronchial epithelial cell lines and primary cells, that both cell proliferation and migration during epithelial repair are delayed in CF compared to non-CF cells. We then demonstrated that ANO1 Cl? channel activity was significantly decreased in CF versus non-CF cells. To explain this decreased Cl? channel activity in CF context, we compared ANO1 expression in non-CF vs. CF bronchial epithelial cell lines and primary cells, in lung explants from wild-type vs. F508del mice and non-CF vs. CF patients. In all these models, ANO1 expression was markedly lower in CF compared to non-CF. Finally, we established that ANO1 inhibition or overexpression was associated respectively with decreases and increases in cell proliferation and migration. In summary, our study demonstrates involvement of ANO1 decreased activity and expression in abnormal CF airway epithelial repair and suggests that ANO1 correction may improve this process. 相似文献
142.
Circadian rhythms in the emergence of S. mansoni cercariae from Biomphalaria tenagophila and B. glabrata, snail hosts of schistosomosis in Brazil, were investigated. A total of 35 specimens of B. tenagophila (São Paulo, Brazil) and 12 B. glabrata (Minas Gerais, Brazil) exposed individually to five miracidia of Schistosoma mansoni originated from the same biotope as their snail hosts, were tested. Observations were carried out at outdoors, with the quantification of cercarial emergence at 3h intervals during three consecutive days in November 1989 and in May 1990. Cercarial emergence was essentially diurnal (from 06.00-18.00h) in both species. Circadian rhythms were detected by the Single Cosinor Method among 74.3% of B. tenagophila and 91.7% of B. glabrata snails. The acrophases corresponding to individual snails were between 11.37 e 17.54h in B. tenagophila and between 14.15 and 16.29h in B. glabrata. These findings confirm our preliminary observations in B. tenagophila and are in accordance to those of other authors in regard to B. glabrata. The acrophases of individual snails were similar within each species, thus indicating that at populacional level cercarial emergence was concentrated in particular times of the day. Group acrophases for each species varied from 13.22 to 15.22h and were not significantly different between B. tenagophila and B. glabrata. Cercariae emerging from B. tenagophila snails seemed to be more sensitive to environmental temperature than those emerging from B. glabrata, at least in the temperature range prevailing along the tests. Further chronobiological studies on host-parasite interactions are encouraged to improve our knowledge about temporal aspects of schistosomosis transmission. 相似文献
143.
EVER1 and 2 confer resistance to cutaneous oncogenic human papillomavirus infections by downregulating the activating protein 1 (AP-1) signaling pathway. Defects in their expression are associated with susceptibility to epidermodysplasia verruciformis, which is characterized by persistent β-HPV infection, tumor necrosis factor alpha (TNF-α) overproduction in keratinocytes and the development of skin cancers. TNF-α-induced apoptosis is a key defense strategy, preventing the persistence of the virus within cells, but the role of EVER proteins in this cell death mechanism triggered by extrinsic stimuli is unknown. We show here that EVER2 induces TNF-α- and TRAIL-dependant apoptosis. It interacts with the N-terminal domain of TRADD, impairs the recruitment of TRAF2 and RIPK1 and promotes apoptosis. The skin cancer-associated EVER2 I306 allele results in an impaired TRADD–EVER2 interaction, with lower levels of cell death following treatment with TNF-α. These data highlight a new, critical function of EVER2 in controlling cell survival in response to death stimuli. 相似文献
144.
Camille Turlure Viktoriia Radchuk Michel Baguette Mark Meijrink Arnold van den Burg Michiel Wallis De Vries Gert‐Jan van Duinen 《Ecology and evolution》2013,3(2):244-254
The butterfly Boloria aquilonaris is a specialist of oligotrophic ecosystems. Population viability analysis predicted the species to be stable in Belgium and to collapse in the Netherlands with reduced host plant quality expected to drive species decline in the latter. We tested this hypothesis by rearing B. aquilonaris caterpillars from Belgian and Dutch sites on host plants (the cranberry, Vaccinium oxycoccos). Dutch plant quality was lower than Belgian one conferring lower caterpillar growth rate and survival. Reintroduction and/or supplementation may be necessary to ensure the viability of the species in the Netherlands, but some traits may have been selected solely in Dutch caterpillars to cope with gradual changes in host plant quality. To test this hypothesis, the performance of Belgian and Dutch caterpillars fed with plants from both countries were compared. Dutch caterpillars performed well on both plant qualities, whereas Belgian caterpillars could not switch to lower quality plants. This can be considered as an environmentally induced plastic response of caterpillars and/or a local adaptation to plant quality, which precludes the use of Belgian individuals as a unique solution for strengthening Dutch populations. More generally, these results stress that the relevance of local adaptation in selecting source populations for relocation may be as important as restoring habitat quality. 相似文献
145.
Pascal Hingamp Nigel Grimsley Silvia G Acinas Camille Clerissi Lucie Subirana Julie Poulain Isabel Ferrera Hugo Sarmento Emilie Villar Gipsi Lima-Mendez Karoline Faust Shinichi Sunagawa Jean-Michel Claverie Hervé Moreau Yves Desdevises Peer Bork Jeroen Raes Colomban de Vargas Eric Karsenti Stefanie Kandels-Lewis Olivier Jaillon Fabrice Not Stéphane Pesant Patrick Wincker Hiroyuki Ogata 《The ISME journal》2013,7(9):1678-1695
Nucleo-cytoplasmic large DNA viruses (NCLDVs) constitute a group of eukaryotic viruses that can have crucial ecological roles in the sea by accelerating the turnover of their unicellular hosts or by causing diseases in animals. To better characterize the diversity, abundance and biogeography of marine NCLDVs, we analyzed 17 metagenomes derived from microbial samples (0.2–1.6 μm size range) collected during the Tara Oceans Expedition. The sample set includes ecosystems under-represented in previous studies, such as the Arabian Sea oxygen minimum zone (OMZ) and Indian Ocean lagoons. By combining computationally derived relative abundance and direct prokaryote cell counts, the abundance of NCLDVs was found to be in the order of 104–105 genomes ml−1 for the samples from the photic zone and 102–103 genomes ml−1 for the OMZ. The Megaviridae and Phycodnaviridae dominated the NCLDV populations in the metagenomes, although most of the reads classified in these families showed large divergence from known viral genomes. Our taxon co-occurrence analysis revealed a potential association between viruses of the Megaviridae family and eukaryotes related to oomycetes. In support of this predicted association, we identified six cases of lateral gene transfer between Megaviridae and oomycetes. Our results suggest that marine NCLDVs probably outnumber eukaryotic organisms in the photic layer (per given water mass) and that metagenomic sequence analyses promise to shed new light on the biodiversity of marine viruses and their interactions with potential hosts. 相似文献
146.
Two methods of measuring primary production, modulated fluorimetry (PAM) and the traditional carbon incorporation method (13C), were compared in four phytoplankton species, two diatoms (Pseudo-nitzschia pungens and Asterionellopsis glacialis), and two dinoflagellates (Heterocapsa sp and Karenia mikimotoï), under N (nitrogen), P (phosphorus) and Si (silicon) limited semi-continuous culture. N and Si-limited cultures showed relatively high quantum efficiency of the PSII (Fv/Fm) values, confirming that Fv/Fm is not a good proxy for nutrient stress in balanced systems, whereas P limitation had a drastic effect on many physiological parameters. In all species, the physiological capacity of phytoplankton cells to acclimate to nutrient limitations led to changes in the cellular biochemical composition and the structure of the photosynthetic apparatus. The observed physiological responses were species and nutrient specific. The values of the chlorophyll-specific absorption cross section (a*) increased with nutrient limitation due to package effect, while the carbon/Chl a ratio was higher under N and P limitations. In diatoms, Si limitation did not affect photosynthesis confirming the uncoupling between Si and carbon metabolisms. In all four species and under all treatments, significant relationships were found between photosynthetic activities, ETRChl (electron transport rate) and PChl (carbon fixation rate) estimated using PAM measurements and 13C incorporation, showing that the fluorescence technique can reliably be used to estimate carbon fixation by phytoplankton. The relationship between ETRChl and PChl can be described by the shape and the slope of the curve (ΦC.e). Linear relationships were found for dinoflagellates and P. pungens under all treatments. A decrease in ΦC.e was observed under N and P limitation probably due to structural damage to the photosynthetic apparatus. A. glacialis showed a logarithmic relationship in N and P limited conditions, due to the alternative electron flow which takes place to optimise photosynthetic performances under high light and/or nutrient stress. 相似文献
147.
Massive Sorghum Collection Genotyped with SSR Markers to Enhance Use of Global Genetic Resources 总被引:2,自引:0,他引:2
Claire Billot Punna Ramu Sophie Bouchet Jacques Chantereau Monique Deu Laetitia Gardes Jean-Louis Noyer Jean-Fran?ois Rami Ronan Rivallan Yu Li Ping Lu Tianyu Wang Rolf T. Folkertsma Elizabeth Arnaud Hari D. Upadhyaya Jean-Christophe Glaszmann C. Thomas Hash 《PloS one》2013,8(4)
Large ex situ collections require approaches for sampling manageable amounts of germplasm for in-depth characterization and use. We present here a large diversity survey in sorghum with 3367 accessions and 41 reference nuclear SSR markers. Of 19 alleles on average per locus, the largest numbers of alleles were concentrated in central and eastern Africa. Cultivated sorghum appeared structured according to geographic regions and race within region. A total of 13 groups of variable size were distinguished. The peripheral groups in western Africa, southern Africa and eastern Asia were the most homogeneous and clearly differentiated. Except for Kafir, there was little correspondence between races and marker-based groups. Bicolor, Caudatum, Durra and Guinea types were each dispersed in three groups or more. Races should therefore better be referred to as morphotypes. Wild and weedy accessions were very diverse and scattered among cultivated samples, reinforcing the idea that large gene-flow exists between the different compartments. Our study provides an entry to global sorghum germplasm collections. Our reference marker kit can serve to aggregate additional studies and enhance international collaboration. We propose a core reference set in order to facilitate integrated phenotyping experiments towards refined functional understanding of sorghum diversity. 相似文献
148.
149.
Olivier Lambert Mélanie Piroux Sophie Puyo Chantal Thorin Monique L'Hostis Laure Wiest Audrey Buleté Frédéric Delbac Hervé Pouliquen 《PloS one》2013,8(6)
Background
The honey bee, Apis mellifera, is frequently used as a sentinel to monitor environmental pollution. In parallel, general weakening and unprecedented colony losses have been reported in Europe and the USA, and many factors are suspected to play a central role in these problems, including infection by pathogens, nutritional stress and pesticide poisoning. Honey bee, honey and pollen samples collected from eighteen apiaries of western France from four different landscape contexts during four different periods in 2008 and in 2009 were analyzed to evaluate the presence of pesticides and veterinary drug residues.Methodology/Findings
A multi-residue analysis of 80 compounds was performed using a modified QuEChERS method, followed by GC-ToF and LC−MS/MS. The analysis revealed that 95.7%, 72.3% and 58.6% of the honey, honey bee and pollen samples, respectively, were contaminated by at least one compound. The frequency of detection was higher in the honey samples (n = 28) than in the pollen (n = 23) or honey bee (n = 20) samples, but the highest concentrations were found in pollen. Although most compounds were rarely found, some of the contaminants reached high concentrations that might lead to adverse effects on bee health. The three most frequent residues were the widely used fungicide carbendazim and two acaricides, amitraz and coumaphos, that are used by beekeepers to control Varroa destructor. Apiaries in rural-cultivated landscapes were more contaminated than those in other landscape contexts, but the differences were not significant. The contamination of the different matrices was shown to be higher in early spring than in all other periods.Conclusions/Significance
Honey bees, honeys and pollens are appropriate sentinels for monitoring pesticide and veterinary drug environmental pollution. This study revealed the widespread occurrence of multiple residues in beehive matrices and suggests a potential issue with the effects of these residues alone or in combination on honey bee health. 相似文献150.
Bianca T. A. de Greef Janneke G. J. Hoeijmakers Emma E. Wolters Hubertus J. M. Smeets Arthur van den Wijngaard Ingemar S. J. Merkies Catharina G. Faber Monique M. Gerrits 《PloS one》2016,11(2)