Patients with liver-related glycogen storage diseases type 1 (GSD1) suffer from life-threatening hypoglycaemia, when left untreated. When treated by an appropriate dieting, patients’ life expectancy improves considerably. Irrespective of current nutritional treatment, however, patients develop major and severe complications, such as liver cancer, end-stage renal failure and severe hyperlipidemia. Until now, the molecular mechanisms involved in these pathologies are poorly understood and available animal models do not survive after weaning. From the retrospective European study in GSD1, we learned that metabolic control appears to be essential to diminish these complications, however by mechanisms still unknown. To gain further insights into the molecular mechanisms of the disease and to evaluate potential treatment strategies, we have recently developed novel mouse models in which the catalytic subunit of glucose-6 phosphatase gene (G6pc) can be deleted specifically and conditionally in each glucose-producing organ. In contrast to total G6pc knockout mice, tissue-specific G6pc deficiency allows mice to maintain their blood glucose by induction of glucose production in the other gluconeogenic organs. Although glucose is considered mainly produced from the liver, liver G6pc-/- mice are perfectly viable and exhibit the same hepatic pathological features as GSD1 patients, including the late development of hepatocellular adenomas and pre-carcinomas (Mutel et al., J. Hepatol., 2011). In this project, the overall aim will be to improve the strategies of treatment on both a nutritional and pharmacological point of view and to identify new means to treat liver, kidney, intestine and metabolic complications. For that, we first propose to decipher the molecular mechanisms underlying the long-term development of the GSD1 pathology, particularly the development of hepatic, renal and intestinal dysfunctions. Since the liver is well suited for gene transfer, the second goal is to test the efficiency and harmlessness of gene therapy in the liver, using new recombinant viral vectors. Molecular studies will be performed to characterize the pathways involved in the development of hepatic tumours in liver G6pc-/- mice. These mice will be fed on different diets to evaluate the impact of different nutrients on the development of tumours. This will allow us studying the relationship with metabolic perturbations in the liver. The characterization of biomarkers of the processes underlying renal complications will be realized in renal G6pc-/- mice studied for more than 18 months. In the same way, long-term complications of intestinal G6pc-/- will be analyzed. The liver G6pc-/- mouse model constitutes also a powerful tool to test the efficiency and safety of recombinant adeno-associated virus (AAV) and lentivirus. Glucose homeostasis, liver pathophysiology and hepatic tumour development will be analyzed in treated mice. The first trials of liver therapy were very promising and showed allow fast progress towards a new therapy of GSD1. This project will provide a better understanding of the development of hepatocellular adenomas and their possible transformation in carcinomas. The study of the liver pathology in liver G6pc-/- mice will permit to establish the link between specific liver metabolic deregulations in GSD1 and the development of liver tumours. This program will also enable us to provide a description of the mechanisms implicated in kidney and intestinal diseases. The outcome of these studies will be translated into new therapeutic dietary and pharmacological measures, and new promising therapeutic options, such as gene therapy, allowing us to strongly improve the long-term outcome and, thereby, the quality of life of GSD1 patients.

The teams involved in this project are interested in gene expression regulation and cytoskeleton roles sustaining pathogenesis of the parasites, Plasmodium falciparum (the agent of malaria) and Entamoeba histolytica (the agent of amoebiasis). These infectious diseases affect humans and are both present and endemic in Mexico. Malaria affects 300-500 million people and 1.5-2 million people, mostly children, die every year as a result of the infection making this one of the most threatening diseases in the World. After malaria, amoebiais is the most lethal disease by a protozoan causing 50 million cases of dysentery and 100,000 deaths from liver abscesses every year. The invasive behavior of these parasites is based on three main activities: motility, adhesion to human tissues (extracellular matrix and cells) and toxic or lytic activity on human cells. Our precedent cell biology approaches have demonstrated the existence of an actin-based mechanism for invasion of human cells or tissues by both parasites. Recently, in P. falciparum, we have discovered an unprecedented role for actin showing that it accumulates at the nuclear periphery, a region that is known for heterochromatin formation that regulates expression of genes involved in pathogenesis such var genes. Actin seems to binds to var intron regions. Lower eukaryotic cells either contain only one actin isoform or isoforms with very few differences as is the case in P. falciparum and E. histolytica. The unique properties of parasite cytoskeleton and the differences in their actin, compared to the human cytoskeleton, have opened avenues for researchers to provide new tools and compounds that able to block the life cycle of these microbes without affecting human survival. With this major goal in mind we will focus our program on parasitic actin, which is the major component of the actin-based cytoskeleton and shows important divergences at the structural level compared with human actin. This project will address the essential question of how actin (and its associated proteins) is involved in the pathogenesis in P. falciparum and E. histolytica. Our aim is (i) to study the dynamics of actin filaments, both cytoplasmic and nuclear; (ii) to determine the role of actin regulation on pathogenesis, including heterochromatin organization, gene expression regulation and microfilament organization during parasite entry into human cells or tissues and (iii) to provide clinical benefit from fundamental research by the identification of new compounds able to block cytoskeleton activities through interaction with actin from these parasites. The proposal is based on the implementation of a consortium with the participation of laboratories from France and Mexico. We particularly aim to produce mutual benefit for both communities by promoting scientific and technological cooperation between the two participating laboratories and countries. To this goal we have built a network in which each member brings a top level of expertise to propose a multidisciplinary program including the uses of modern technologies such as imaging live cell processes, epigenetic studies and screening of new anti-parasitic compounds (based on computational modelling). This project represents the first and the most comprehensive study on the role of actin in the outcome of two major infectious diseases. It will give new understanding on the process of parasite infections, and allow us to use this information to generate new approaches against parasite spread.

A global increase in the demand for wood products has been observed worldwide during the last decades. This trend is expected to continue in the future as a consequence of population growth. Additionally, the need for wood is augmented by the increasing substitution of fossil energy by wood biomass-based energy to mitigate greenhouse gas emissions. This demand will not be satisfied by natural and naturally regenerated forests: they are threatened by high deforestation rates and forest degradation mainly in the tropics and the costs of wood mobilization in the temperate zones is a concern. Forest plantations (FP) are therefore expected to provide a large part of the global wood supply. Their ability to meet wood demand is limited by competing land uses. Higher stand yields must be obtained on soils that may not necessarily support such intensification especially as nitrogen (N) and phosphorus (P) exportations by biomass removal are generally not offset by fertilization. Therefore, FP sustainability is currently a major concern, particularly with regard to serious long-term N and P deficits. Innovative FP management schemes, and attractive to the stakeholders must be then deployed. The Intens&Fix project will deal with the ecological intensification of FP through the association of N2-fixing species (NFS) with the goal to increase stand production as, in particular, a result of better N and P availability in the soil. These systems hould combine positive environmental impacts while ensuring social-economical improvement of livelihood for smallholders or performances for commercial companies. The project will develop an experimental approach on various and complementary FP with associated NFS, both in France (Juglans sp. and Alnus cordata or herbaceous NFS in Languedoc, Populus sp + Robinia pseudoacacia. in North-Est of France) and in the Tropics (mixed-species plantations of Eucalyptus grandis and Acacia mangium in Brazil and Congo). An integrated biophysical model will be developed for the simulation of mixed species in FP. Outputs of virtual experiments performed with the biophysical model will feed a plantation-level model allowing to assess the economical feasibility and to test decision rules for the management of FP with NFS. Crossing models outputs and a survey of stakeholders’ innovation process concerning the use of NFS will entitle us to assess the potential development of these systems. The approach will be multidisciplinary and involve scientists working in ecophysiology, biogeochemistry, soil science, microbiology, silviculture, socio-economics, and modelling. This project will contribute to the production of innovative results i.e. refined methodological techniques for estimation of N transfer, documentation of mechanisms of competition/ facilitation for N and P bioavailability, model coupling water, N and C functioning adapted to mixed-species forests and practices (species, density…) to manage NFS in FP, and socio-economical assessment of these new management schemes. The results will be valorised through publications in high level scientific journals, as well as in R/D journals and participation to international conferences. More generally the involvement of a top resource partner in farm forestry and agroforestry, the participative approach deployed, and the strong partnership developed with producer organisations in France, Brazil and Congo will warrant a large and efficient dissemination of the Intens&Fix results. From an operational view point, the Intens&Fix project will provide tools of ecological intensification to significantly improve FP management with specific targets in eucalyptus plantations in Congo and Brazil (several millions ha), Very Short Rotation Coppices, and high value timber in agroforestry systems (potential of several millions ha in Europe).

Influenza of type A causes a severe viral infection of the respiratory system. It has been at the origin of some of the worst epidemics in the history of mankind and continues to be a major health concern. Although vaccination is the primary strategy for the prevention of influenza infections during epidemics, vaccine production by current methods cannot be carried out at the pace required to stop the progress of a new strain of the influenza virus. Also, recent alarming reports on the emergence of drug resistance make the development of new anti-influenza molecules a priority. Therefore, effective antiviral agents are required to prepare for a pandemic. In this general context, it is our intention to develop a discovery program for new constructs specifically directed against hemagglutinin (H) and the enzyme neuraminidase (N), both crucial glycoproteins for the viral infection and important targets for drug development, with a special focus on the proteins of the H1N1 and H5N1 strains. The availability of such drugs would also make possible combined drug therapies to prevent the selection of resistant viruses. Infections by Influenza viruses of type A have a significant impact on public health and economy and therefore justify the availability of effective new generations of therapeutics to control viral outbreaks. SIALIFLU specifically aims at discovering new selective binders of neuraminidase 1 that target the catalytic site as well as the newly identified "150-cavity" of the enzyme. The synthesis of new neuraminidase inhibitors will be based on a dihydropyranyl skeleton, utilizing palladium and boron chemistries. It is also intended to identify new multivalent constructs that efficiently interact with the hemagglutinin receptor. This second synthetic objective of this project will exploit samarium diiodide mediated coupling processes and reactions of the "click" chemistry. The chemistry work will be strongly associated and guided by modeling studies and enzymatic, binding and structural studies with the targeted proteins. In the course of this project in synthetic chemistry, we also anticipate the identification of new synthetic routes to sialic acids and derivatives as well as the unraveling of novel organometallic access to these important carbohydrates. There is intense research interest in sialic acid chemistry [N-acetylneuraminic acid (Neu5Ac) conjugates and modified structures] owing to its significant role in physiological processes and diseases. To address this goal, we propose five complementary approaches in synthetic chemistry, molecular modeling and structural biology: - The drug design by molecular modeling of inhibitors targeting the open conformation of neuraminidase 1, - The synthesis of new derivatives targeting the open conformation of neuraminidase subtype 1 (Palladium and conjugate chemistry) - The de novo synthesis of derivatives modified at the C-6 position and/or possessing a phosphonate polar group, targeting neuraminidase (Boron chemistry) - The synthesis of robust C-sialoside multimers for hemagglutinin binding inhibition (Samarium and "click" chemistry) - The structural biology on hemagglutinin and neuraminidase 1 and evaluation of the bio-activities of the newly prepared molecules.