Molecular coupling of Xist regulation and pluripotency   总被引：2，自引：0，他引：2  

Navarro P  Chambers I  Karwacki-Neisius V  Chureau C  Morey C  Rougeulle C  Avner P 《Science (New York, N.Y.)》2008,321(5896):1693-1695

During mouse embryogenesis, reversion of imprinted X chromosome inactivation in the pluripotent inner cell mass of the female blastocyst is initiated by the repression of Xist from the paternal X chromosome. Here we report that key factors supporting pluripotency-Nanog, Oct3/4, and Sox2-bind within Xist intron 1 in undifferentiated embryonic stem (ES) cells. Whereas Nanog null ES cells display a reversible and moderate up-regulation of Xist in the absence of any apparent modification of Oct3/4 and Sox2 binding, the drastic release of all three factors from Xist intron 1 triggers rapid ectopic accumulation of Xist RNA. We conclude that the three main genetic factors underlying pluripotency cooperate to repress Xist and thus couple X inactivation reprogramming to the control of pluripotency during embryogenesis.  相似文献   

Sterilization of exopolysaccharides produced by deep-sea bacteria: impact on their stability and degradation     

Rederstorff E  Fatimi A  Sinquin C  Ratiskol J  Merceron C  Vinatier C  Weiss P  Colliec-Jouault S 《Marine drugs》2011,9(2):224-241

Polysaccharides are highly heat-sensitive macromolecules, so high temperature treatments are greatly destructive and cause considerable damage, such as a great decrease in both viscosity and molecular weight of the polymer. The technical feasibility of the production of exopolysaccharides by deep-sea bacteria Vibrio diabolicus and Alteromonas infernus was previously demonstrated using a bioproduct manufacturing process. The objective of this study was to determine which sterilization method, other than heat sterilization, was the most appropriate for these marine exopolysaccharides and was in accordance with bioprocess engineering requirements. Chemical sterilization using low-temperature ethylene oxide and a mixture of ionized gases (plasmas) was compared to the sterilization methods using gamma and beta radiations. The changes to both the physical and chemical properties of the sterilized exopolysaccharides were analyzed. The use of ethylene oxide can be recommended for the sterilization of polysaccharides as a weak effect on both rheological and structural properties was observed. This low-temperature gas sterilizing process is very efficient, giving a good Sterility Assurance Level (SAL), and is also well suited to large-scale compound manufacturing in the pharmaceutical industry.  相似文献   

Painful Sting After Exposure to Dendrocnide sp: Two Case Reports     

Corinne Schmitt  Philippe Parola  Luc de Haro 《The Forestry Chronicle》2013,24(4):471-473

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Unusual Glycosaminoglycans from a Deep Sea Hydrothermal Bacterium Improve Fibrillar Collagen Structuring and Fibroblast Activities in Engineered Connective Tissues     

Karim Senni  Farida Gueniche  Sylvie Changotade  Dominique Septier  Corinne Sinquin  Jacqueline Ratiskol  Didier Lutomski  Gaston Godeau  Jean Guezennec  Sylvia Colliec-Jouault 《Marine drugs》2013,11(4):1351-1369

Biopolymers produced by marine organisms can offer useful tools for regenerative medicine. Particularly, HE800 exopolysaccharide (HE800 EPS) secreted by a deep-sea hydrothermal bacterium displays an interesting glycosaminoglycan-like feature resembling hyaluronan. Previous studies demonstrated its effectiveness to enhance in vivo bone regeneration and to support osteoblastic cell metabolism in culture. Thus, in order to assess the usefulness of this high-molecular weight polymer in tissue engineering and tissue repair, in vitro reconstructed connective tissues containing HE800 EPS were performed. We showed that this polysaccharide promotes both collagen structuring and extracellular matrix settle by dermal fibroblasts. Furthermore, from the native HE800 EPS, a low-molecular weight sulfated derivative (HE800 DROS) displaying chemical analogy with heparan-sulfate, was designed. Thus, it was demonstrated that HE800 DROS mimics some properties of heparan-sulfate, such as promotion of fibroblast proliferation and inhibition of matrix metalloproteinase (MMP) secretion. Therefore, we suggest that the HE800EPS family can be considered as an innovative biotechnological source of glycosaminoglycan-like compounds useful to design biomaterials and drugs for tissue engineering and repair.  相似文献   

Nematodes, indicators of the origin of the soil used by termites to construct biostructures     

Cécile Villenave  Djibril Djigal  Corinne Rouland-Lefevre 《Pedobiologia》2009,52(5):301-307

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Banning of methyl bromide for seed treatment: could Ditylenchus dipsaci again become a major threat to alfalfa production in Europe?     

Raphaëlle Mouttet  Abraham Escobar‐Gutiérrez  Magali Esquibet  Laurent Gentzbittel  Didier Mugniéry  Philippe Reignault  Corinne Sarniguet  Philippe Castagnone‐Sereno 《Pest management science》2014,70(7):1017-1022

In Europe, the stem and bulb nematode Ditylenchus dipsaci has been listed as a quarantine pest by EPPO: without any control, it may cause complete failure of alfalfa crops. Movement of nematodes associated with seeds is considered to be the highest‐risk pathway for the spread of this pest. Since the 2010 official withdrawal of methyl bromide in Europe, and in the absence of any alternative chemical, fumigation of contaminated seed batches is no longer possible, which makes the production of nematode‐free alfalfa seeds difficult to achieve and leads to unmarketable seed batches. Thermotherapy is being considered as a realistic alternative strategy, but its efficiency still remains to be validated. The combination of the currently available methods (i.e. use of resistant cultivars, seed production according to a certification scheme, mechanical sieving, seed batch inspection) could significantly reduce the likelihood of seed contamination. However, it does not guarantee a total eradication of the nematode. Although it is already widely distributed all over Europe, reclassification of D. dipsaci as a regulated non‐quarantine pest to reduce the possibility of further introductions and the rate of spread of this pest appears to be a risky strategy because of the lack of up‐to‐date documented data to evaluate damage thresholds and determine acceptable tolerance levels. [[ArtCopyrightmsg]]  相似文献   

A simple and efficient method for the long-term preservation of plant cell suspension cultures     

Anne-Marie Boisson  Elisabeth Gout  Richard Bligny  Corinne Rivasseau 《Plant methods》2012,8(1):4

Background  

The repeated weekly subculture of plant cell suspension is labour intensive and increases the risk of variation from parental cells lines. Most of the procedures to preserve cultures are based on controlled freezing/thawing and storage in liquid nitrogen. However, cells viability after unfreezing is uncertain. The long-term storage and regeneration of plant cell cultures remains a priority.  相似文献   

The potential for carbon offset trading to provide added incentive to adopt silvopasture and alley cropping in Missouri     

Jason Holderieath  Corinne Valdivia  Larry Godsey  Carla Barbieri 《Agroforestry Systems》2012,86(3):345-353

Global carbon trading may present a unique opportunity to change the rural landscape by allowing landowners to make an environmental impact with financial incentives. By enticing point source polluters to trade to an optimal level of pollution by offsetting their emissions with compatible carbon reduction projects, markets are able to facilitate a cleaner environment. Agroforestry provides a set of practices that can sequester carbon with managed tree and crop plantings. However, the initial lack of financial resources has been an obstacle to its adoption in the United States. This paper explores the potential for carbon offset trading to provide an added incentive to adopt agroforestry practices. Chicago Climate Exchange carbon sequestration projects are used as a baseline assessment, and the requirements that Missouri landowners would need to do in terms of contracting and ownership are identified. Data from landowners in central Missouri and the Ozarks (353 individuals) are used to determine characteristics of potentially interested landowners in agroforestry. A model to evaluate agroforestry profitability scenarios is used to compare the added carbon credit trading revenue to traditional alternate uses for the property. The findings from this analysis indicate that in the current context carbon trading does not provide an added incentive value for Missouri landowners to adopt either silvopasture or alley cropping practices because of the low magnitude of annual return.  相似文献   

First Described Envenomation by Centruroides pococki Scorpion in the French Caribbean Island Guadeloupe     

Corinne Schmitt  Romain Torrents  Nicolas Simon  Luc de Haro 《The Forestry Chronicle》2017,28(2):159-160

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Plasticity of animal genome architecture unmasked by rapid evolution of a pelagic tunicate     

Denoeud F  Henriet S  Mungpakdee S  Aury JM  Da Silva C  Brinkmann H  Mikhaleva J  Olsen LC  Jubin C  Cañestro C  Bouquet JM  Danks G  Poulain J  Campsteijn C  Adamski M  Cross I  Yadetie F  Muffato M  Louis A  Butcher S  Tsagkogeorga G  Konrad A  Singh S  Jensen MF  Cong EH  Eikeseth-Otteraa H  Noel B  Anthouard V  Porcel BM  Kachouri-Lafond R  Nishino A  Ugolini M  Chourrout P  Nishida H  Aasland R  Huzurbazar S  Westhof E  Delsuc F  Lehrach H  Reinhardt R  Weissenbach J  Roy SW  Artiguenave F  Postlethwait JH  Manak JR  Thompson EM 《Science (New York, N.Y.)》2010,330(6009):1381-1385

Genomes of animals as different as sponges and humans show conservation of global architecture. Here we show that multiple genomic features including transposon diversity, developmental gene repertoire, physical gene order, and intron-exon organization are shattered in the tunicate Oikopleura, belonging to the sister group of vertebrates and retaining chordate morphology. Ancestral architecture of animal genomes can be deeply modified and may therefore be largely nonadaptive. This rapidly evolving animal lineage thus offers unique perspectives on the level of genome plasticity. It also illuminates issues as fundamental as the mechanisms of intron gain.  相似文献