Demethylation of DNA by purified chick embryo 5-methylcytosine-DNA glycosylase requires both protein and RNA

We have previously purified and characterized a 5-methylcytosine (5-MeC)-DNA glycosylase from 12 day old chick embryos [Jost,J.P. et al. (1995) J. Biol. Chem. 270, 9734-9739]. The activity of the purified enzyme is abolished upon treatment with proteinase K and ribonuclease A. RNA copurifies with 5-MeC-DNA glycosylase activity throughout all chromatographic steps and preparative gel electrophoresis. RNA with a length of ∼300-500 nucleotides was isolated from the gel purified enzyme. Upon extensive treatment with proteinase K, the gel eluted and labeled RNA did not show any significant change in molecular mass. The purified RNA incubated alone or in the presence of Mg2+ and deoxyribonucleotide phosphates had no 5-MeC-DNA glycosylase or demethylating activities. However, activity of 5-MeC-DNA glycosylase could be restored when the purified RNA was incubated with the inactive protein, free of RN

Evaluation of therapeutic properties of fermented vegetables extract (OM-X®) in the model of colitis induced by Citrobacter rodentium in mice

AbstractInfection of mice with Citrobacter rodentium serves as a model to study human intestinal infections. C. rodentium infection leads to increased production of inflammatory cytokines, immune cell infiltration and damage to the gut barrier. We used this model of colitis to evaluate the therapeutic properties of OM-X®, an extract prepared by fermentation of vegetables, seaweeds, fruits and mushrooms. Administration of OM-X® to C. rodentium-infected mice reduced damage to the intestinal epithelium, lowered inflammation scores, increased IL-10 expression and maintained FoxP3 gene expression. OM-X® also partially prevented bacterial translocation, increased expression of tight junction genes and increased proliferation of epithelial cells. PCR analysis of stool samples showed that OM-X® significantly reduced the populations of bacteria harboring buk gene (mostly Clostridium species). It is suggested that alterations of microbiota composition, following OM-X® consumption, contribute to protection against infection and epithelial damage, and lead to an increased expression of anti-inflammatory cytokines

The Sustainable Forest Management Indicators for 2010 – A Testimony

Indicators for Sustainable Forest Management (SFM) are involved in two periodic tasks, at a global level for the UNO FAO (Forest Resources Assessment) and at a Pan-European level for the Ministerial Conference on the Protection of Forests in Europe (MCPFE, now Forest Europe). Both operations are based on convergent concepts and periodicity. Focusing on the specificities of the French forests, the national process completes the Pan-European process at the same 5-year pace. The French National Inventory, at the request of the Ministry for Forests, led the 2010 process, both directly by providing its own data and by collecting complementary data from other providers. The 2010 reference document comprises 35 European indicators and 19 French indicators, organized following the six SFM criteria commonly referred to as the Helsinki criteria. In comparison with the former national report in 2005, eight national indicators could not be maintained, because of a lack of relevance or a lack of data. Seven others were added. The steering committee duly recorded the problems encountered and solutions applied, and made recommendations for the next exercise in 2015. In comparison with the 2005 exercise, two major deviations were noticed in the data provided by the two main providers. The French National Inventory had changed its statistical method and adopted the international definition of forests. The Department for Statistics and Forecasting changed the national sample for its TERUTI-LUCAS survey. To facilitate the next exercise in 2015, the various stakeholders agreed to participate in working sessions led by the Ministry for Forests.L’exercice 2010 de la constitution des indicateurs de gestion forestière durable s’inscrit dans le rapportage quasi concomitant de deux opérations internationales, l’une au bénéfice de la conférence ministérielle sur la protection des forêts en Europe, désormais Forest Europe, l’autre pour le compte de l’Organisation des Nations unies pour l’alimentation et l’agriculture (FAO) dans le processus d’évaluation des ressources forestières mondiales. Ces deux opérations sont fondées sur des concepts et des rythmes désormais largement convergents. Axé sur les spécificités de la forêt métropolitaine, le processus national complète le processus européen au même rythme quinquennal. À la demande du ministère chargé des forêts, l’Inventaire forestier national a conduit l’opération de constitution des indicateurs de gestion forestière directement à partir de ses données propres ou indirectement en collectant les données de quelque vingt fournisseurs. Le document de référence ainsi constitué rassemble trente-cinq indicateurs européens et dix-neuf indicateurs nationaux organisés selon les six critères de la gestion forestière durable, dits critères d’Helsinki. Pour ce faire, un comité de pilotage a été réuni quatre fois entre septembre 2009 et avril 2011. Par rapport à la précédente version (2005) huit indicateurs nationaux n’ont pas été retenus, faute de pertinence ou faute de données, sept autres ont été ajoutés. Le comité a dûment documenté les problèmes rencontrés, les solutions retenues et a émis des recommandations pour le prochain exercice. Par rapport à la version 2005, des ruptures majeures ont été enregistrées chez les deux principaux fournisseurs de données: l’IFN a changé de méthode statistique et a adopté la définition internationale de la forêt, le Service de statistique et de prospective (SSP) a changé l’échantillon national de son enquête Teruti-Lucas. Dans le but de faciliter le prochain exercice semblable en 2015, il est convenu que des travaux d’intersession puissent réunir les parties prenantes et être conduits sous l’égide du ministère chargé des forêts

Regulation of allergy by Fc receptors.

The aggregation of high-affinity IgE receptors (FcepsilonRI) on mast cells and basophils has long been known as the critical event that initiates allergic reactions. Monomeric IgE was recently found to induce a variety of effects when binding to FcepsilonRI. Upregulation of FcepsilonRI only requires binding, whereas other responses require FcepsilonRI aggregation. Interestingly, FcepsilonRI aggregation has recently been understood to generate a mixture of positive and negative intracellular signals. Mast cells and basophils also express low-affinity and, under specific conditions, high-affinity IgG receptors. When co-engaging these receptors with FcepsilonRI, IgG antibodies can amplify or dampen IgE-induced mast cell activation. On the basis of these findings, it has been proposed that FcRs can be used as targets and/or tools for new therapeutic approaches to allergies

Set-in LifeLong Learning for PhD students in Electrical and Information Engineering

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Proceedings of the 28th European Symposium on the reliability of electron devices, failure physics and analysis

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Proceedings of the 32nd European Symposium on the Reliability of Electron Devices, Failure Physics and Analysis

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The RNA moiety of chick embryo 5-methylcytosine- DNA glycosylase targets DNA demethylation

We have previously shown that DNA demethylation by chick embryo 5-methylcytosine (5-MeC)-DNA glycosylase needs both protein and RNA. RNA from enzyme purified by SDS-PAGE was isolated and cloned. The clones have an insert ranging from 240 to 670 bp and contained on average one CpG per 14 bases. All six clones tested had different sequences and did not have any sequence homology with any other known RNA. RNase-inactivated 5-MeC-DNA glycosylase regained enzyme activity when incubated with recombinant RNA. However, when recombinant RNA was incubated with the DNA substrate alone there was no demethylation activity. Short sequences complementary to the labeled DNA substrate are present in the recombinant RNA. Small synthetic oligoribonucleotides (11 bases long) complementary to the region of methylated CpGs of the hemimethylated double-stranded DNA substrate restore the activity of the RNase-inactivated 5-MeC-DNA glycosylase. The corresponding oligodeoxyribonucleotide or the oligoribonucleotide complementary to the non-methylated strand of the same DNA substrate are inactive when incubated in the complementation test. A minimum of 4 bases complementary to the CpG target sequence are necessary for reactivation of RNase-treated 5-MeC-DNA glycosylase. Complementation with double-stranded oligoribonucleotides does not restore 5-MeC-DNA glycosylase activity. An excess of targeting oligoribonucleotides cannot change the preferential substrate specificity of the enzyme for hemimethylated double-stranded DN

PhD in Electrical and Information Engineering in Europe: Towards a harmonization including LifeLong Learning

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