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Plant pathogens often adapt to plant genetic resistance so characterization of the architecture under-lying such an adaptation is required to understand the adaptive potential of pathogen populations. Erosion of banana quantitative resistance to a major leaf disease caused by polygenic adaptation of the causal agent, the fungus Pseudocercospora fijiensis, was recently identified in the northern Caribbean region. Genome scan and quantitative genetics approaches were combined to investigate the adaptive architecture underlying this adaptation. Thirty-two genomic regions showing host se-lection footprints were identified by pool sequencing of isolates collected from seven plantation pairs of two cultivars with different levels of quantitative resistance. Individual sequencing and phenotyping of isolates from one pair revealed significant and variable levels of correlation be-tween haplotypes in 17 of these regions with a quantitative trait of pathogenicity (the diseased leaf area). The multilocus pattern of haplotypes detected in the 17 regions was found to be highly varia-ble across all the population pairs studied. These results suggest complex adaptive architecture un-derlying plant pathogen adaptation to quantitative resistance with a polygenic basis, redundancy, and a low level of parallel evolution between pathogen populations. Candidate genes involved in quantitative pathogenicity and host adaptation of P. fijiensis were highlighted in genomic regions combining annotation analysis with available biological data.

International audience; Plant pathogens often adapt to plant genetic resistance so characterization of the architecture underlying such an adaptation is required to understand the adaptive potential of pathogen populations. Erosion of banana quantitative resistance to a major leaf disease caused by polygenic adaptation of the causal agent, the fungus Pseudocercospora fijiensis, was recently identified in the northern Caribbean region. Genome scan and quantitative genetics approaches were combined to investigate the adaptive architecture underlying this adaptation. Thirty-two genomic regions showing host selection footprints were identified by pool sequencing of isolates collected from seven plantation pairs of two cultivars with different levels of quantitative resistance. Individual sequencing and phenotyping of isolates from one pair revealed significant and variable levels of correlation between haplotypes in 17 of these regions with a quantitative trait of pathogenicity (the diseased leaf area). The multilocus pattern of haplotypes detected in the 17 regions was found to be highly variable across all the population pairs studied. These results suggest complex adaptive architecture underlying plant pathogen adaptation to quantitative resistance with a polygenic basis, redundancy, and a low level of parallel evolution between pathogen populations. Candidate genes involved in quantitative pathogenicity and host adaptation of P. fijiensis were identified in genomic regions by combining annotation analysis with available biological data.

International audience; Understanding the mechanisms involved in pathogen adaptation to quantitative resistance in plants has a key role to play in establishing durable strategies for resistance deployment, especially in perennial crops. The erosion of quantitative resistance has been recently suspected in Cuba and the Dominican Republic for a major fungal pathogen of such a crop: Pseudocercospora fijiensis, causing black leaf streak disease on banana. This study set out to test whether such erosion has resulted from an adaptation of P. fijiensis populations, and to determine whether or not the adaptation is local. Almost 600 P. fijiensis isolates from Cuba and the Dominican Republic were sampled using a paired-population sampling design on resistant and susceptible banana varieties. A low genetic structure of the P. fijiensis populations was detected in each country using 16 microsatellite markers. Cross-inoculation experiments using isolates from susceptible and resistant cultivars were carried out, measuring a quantitative trait (the diseased leaf area) related to pathogen fitness on three varieties. A further analysis based on those data suggested the existence of a local pattern of adaptation to resistant cultivars in both of the study countries, due to the existence of specific (or genotype by genotype) host-pathogen interactions. However, neither cost nor benefit effects for adapted populations were found on the widely used "Cavendish" banana group. These results highlight the need to study specific host-pathogen interactions and pathogen adaptation on a wide range of quantitative resistance phenotypes in banana, in order to develop durable strategies for resistance deployment.

International audience; Among the emerging fungal diseases threatening food security, the Pseudocercospora fijiensis fungus causing black leaf streak disease of banana is one of the most marked examples of a recent worldwide pandemic on a major crop. We assessed how this pathogen spread throughout the latest invaded region, i.e. Central America and the Caribbean. We retraced its population history combining detailed monitoring information on disease outbreaks and population genetic analyses based on large-scale sampling of P. fijiensis isolates from 121 locations throughout the region. The results first suggested that sexual reproduction was not lost during the P. fijiensis expansion, even in the insular Caribbean context, and a high level of genotypic diversity was maintained in all the populations studied. The population genetic structure of P. fijiensis and historical data showed that two disease waves swept northward and southward in all banana-producing countries in the study area from an initial entry point in Honduras, probably mainly through gradual stepwise spore dispersal. Serial founder events accompanying the northern and southern waves led to the establishment of two different genetic groups. A different population structure was detected on the latest invaded islands (Martinique, Dominica and Guadeloupe), revealing multiple introductions and admixture events that may have been partly due to human activities. The results of this study highlight the need to step up surveillance to limit the spread of other known emerging diseases of banana spread mainly by humans, but also to curb gene flow between established pathogen populations which could increase their evolutionary potential.

Dinitroanilines are chemical compounds with high selectivity for plant cell &alpha, tubulin in which they promote microtubule depolymerization. They target &alpha, tubulin regions that have diverged over evolution and show no effect on non-photosynthetic eukaryotes. Hence, they have been used as herbicides over decades. Interestingly, dinitroanilines proved active on microtubules of eukaryotes deriving from photosynthetic ancestors such as Toxoplasma gondii and Plasmodium falciparum, which are responsible for toxoplasmosis and malaria, respectively. By combining differential in silico screening of virtual chemical libraries on Arabidopsis thaliana and mammal tubulin structural models together with cell-based screening of chemical libraries, we have identified dinitroaniline related and non-related compounds. They inhibit plant, but not mammalian tubulin assembly in vitro, and accordingly arrest A. thaliana development. In addition, these compounds exhibit a moderate cytotoxic activity towards T. gondii and P. falciparum. These results highlight the potential of novel herbicidal scaffolds in the design of urgently needed anti-parasitic drugs.

This article aims at analyzing the economic impact of a particular category of the population, the retirees, on the development of rural areas. A great number of them are indeed confronted with the presence or the arrival of retirees, whose impact has seldom been assessed in France. However, the stakes are important in terms of local development strategies. To gain deeper insight into this issue, a hybrid model between Keynesian and economic base theories has been applied to a small zone of the Limousin (Bourganeuf), that is largely confronted with this question. We have highlighted the important impact of retirees on local employment (about 40 % of tertiary employment). Although the new-come pensioners profit from higher incomes, the local impact remains limited because of a high proportion of external expenditures. Lastly, the implementation of an innovating policy (gerontologic coordination) allows the maintenance of a significant number old people and also of indirect employment (in particular in hospitals) which represents 8 % of total employment.

Social learning is a highly adaptive process by which an animal acquires information from a conspecific. While estrogens are known to modulate learning and memory, much of this research focuses on individual learning. Estrogens have been shown to enhance social learning on a long-term time scale, likely via genomic mechanisms. Estrogens have also been shown to affect individual learning on a rapid time scale through cell-signaling cascades, rather than via genomic effects, suggesting they may also rapidly influence social learning. We therefore investigated the effects of 17β-estradiol and involvement of the estrogen receptors (ERs) using the ERα agonist propyl pyrazole triol, the ERβ agonist diarylpropionitrile, and the G protein-coupled ER 1 (GPER1) agonist G1 on the social transmission of food preferences (STFP) task, within a time scale that focused on the rapid effects of estrogens. General ER activation with 17β-estradiol resulted in a modest facilitation of social learning, with mice showing a preference up to 30min of testing. Specific activation of the GPER1 also rapidly enhanced social learning, with mice showing a socially learned preference up to 2h of testing. ERα activation instead shortened the expression of a socially learned food preference, while ERβ activation had little to no effects. Thus, rapid estrogenic modulation of social learning in the STFP may be the outcome of competing action at the three main receptors. Hence, estrogens' rapid effects on social learning likely depend on the specific ERs present in brain regions recruited during social learning.

International audience; Increasing temperature of seawater is often associated with increased exposure incidence of disease in field and in aquaculture populations. Numerous episodic mass mortalities of the abalone Haliotis tuberculata have been observed along the northern Brittany coast of France caused by a complex interaction between the host, pathogen and environmental factors. Here, we evaluated the potential of high-resolution melting (HRM) analysis for mutation genotyping and development of genetic markers for resistance to vibriosis in the gastropod species H. tuberculata. Small amplicon assays were developed and revealed genetic polymorphism between surviving and susceptible abalone obtained after two successive infections of aquaculture families in controlled conditions. Together with specific COI haplotypes, we identified particular genotypes in nascent polypeptide-associated complex subunit alpha and ferritin genes linked to the susceptibility or resistance of abalone to vibriosis. Selection of genitors based on these genes may increase the proportion in offspring of resistant individuals of more than 76 %. Finally, HRM assays constitute a very efficient genotyping tool to validate the genetic markers on a representative number of individuals of wild populations and thus identify future resistant genitors for aquaculture or conservation purposes

Newcomers and areas management the example of Auvergne - After decades of rural drift, rural areas today experience a new demographic dynamism. Yet all the rural areas are not concerned by this trend. The Auvergne and the Limousin keep losing population habitants because of a natural and the young'continuous going away from their region. Here and there, however, the arrival of a new population can be seen. Given the stake they represent for the future of less favoured areas, it seems relevant to survey to population of newcomers and to define the strategies for attracting population. Building on the work done on 5 rural areas in the Auvergne, the article presents these new populations' characteristics and offers an analysis of the newcomers' representations and behaviours and tries to interpret the differences in attractiveness among these areas., Après des décennies d'exode, l'espace rural connaît aujourd'hui de nouvelles dynamiques démographiques. Tous les espaces ruraux ne sont cependant pas concernés par ces tendances : ainsi l'Auvergne et le Limousin continuent de perdre des habitants du fait d'un déficit naturel persistant et d'un départ continu de jeunes hors région. Ici et là, cependant, on constate l'arrivée de nouvelles populations. Considérant l'enjeu qu'elles représentent pour le devenir de ces espaces ruraux fragiles, il a paru pertinent de conduire une étude pour mieux connaître la population des nouveaux venus et les stratégies des territoires face à l'accueil de nouvelles populations. L'article présente à partir des travaux conduits sur cinq territoires ruraux d'Auvergne, les caractéristiques de ces nouvelles populations, propose une analyse des représentations et des comportements des nouveaux venus et tente d'interpréter les différences d'attractivité entre territoires., Roussel Véronique, Mamdy Jean-François. Nouveaux venus et organisation des territoires. L'exemple de l'Auvergne. In: Économie rurale. N°257, 2000. pp. 56-66.

The public services policy in rural areas : from what has been said to what has been done For a long time, the keeping up of the public services was considered as one of the priorities of the policy for rural development. Then the right to exist for "the - public - service- for - all 'was put forward, this right being part of the general principles of our constitution. Since the eighties, ideas have changed. The appearance of the logic of modernization in accordance with what was called the "renewal policy " of the public service - a policy set up by Michel Rocard in a circular of February 23rd) 989 - appears as a need both for the producers and the consumers, a condition of profitability for the former, a condition of quality for the latter. To implement this new policy, the instructions at the level of the "département" for the organization and improvement of the services have to be defined and commissions, at the level of the "département" too, have to be set up according to a partnership which must be as wide as possible. What is the meaning of such a policy ? What are the consequences for the rural public services ? The analysis of this policy raises many questions as far as the aims and the modes of enforcement are concerned. Furthermore it does not look to take enough into account the realities of the rural world and more particularly that of the rural areas which are said to be hard to live in., Pendant longtemps, le maintien des services publics a été considéré comme l'une des priorités de la politique d'aménagement rural. On invoquait alors le droit à l'existence du service public pour tous, droit inscrit dans les principes généraux de notre constitution. A partir des années 1 980, le discours change. L'introduction d'une logique de modernisation conforme à la politique dite de renouveau du service public- politique mise en place par Michel Rocard dans une circulaire du 23 février 1989 - apparaît comme une nécessité pour les producteurs comme pour les consommateurs, condition de rentabilité pour les premiers, condition de qualité pour les seconds. Pour permettre l'application de cette nouvelle politique, des schémas départementaux d'organisation et d'amélioration des services doivent être élaborés et des commissions départementales doivent être constituées sur la base d'un partenariat qui doit être le plus large possible. La signification d'une telle politique ? Quelles conséquences pour les services publics ruraux ? L'analyse de cette politique fait ressortir de nombreuses interrogations quant aux objectifs et modalités d'application. De plus, il semblerait qu'elle prenne insuffisamment en compte les réalités du monde rural et plus particulièrement celle des zones rurales dites difficiles, Roussel Véronique. La politique des services publics dans l'espace rural : du discours aux pratiques. In: Économie rurale. N°238, 1997. Représentation politique et sociologique du monde agricole et rural français. 2e partie. pp. 28-32.

Background Primary or secondary abnormalities of glycosylation have been reported in various brain diseases. Decreased asialotransferrin to sialotransferrin ratio in cerebrospinal fluid (CSF) is a diagnostic marker of leukodystrophies related to mutations of genes encoding translation initiation factor, EIF2B. We investigated the CSF glycome of eIF2B-mutated patients and age-matched normal individuals in order to further characterize the glycosylation defect for possible use as a biomarker. Methodology/Principal Findings We conducted a differential N-glycan analysis using MALDI-TOF/MS of permethylated N-glycans in CSF and plasma of controls and eIF2B-mutated patients. We found in control CSF that tri-antennary/bisecting and high mannose structures were highly represented in samples obtained between 1 to 5 years of age, whereas fucosylated, sialylated structures were predominant at later age. In CSF, but not in plasma, of eIF2B-mutated patient samples, we found increased relative intensity of bi-antennary structures and decreased tri-antennary/bisecting structures in N-glycan profiles. Four of these structures appeared to be biomarker candidates of glycomic profiles of eIF2B-related disorders. Conclusion Our results suggest a dynamic development of normal CSF N-glycan profiles from high mannose type structures to complex sialylated structures that could be correlated with postnatal brain maturation. CSF N-glycome analysis shows relevant quantitative changes associated with eIF2B related disorders. This approach could be applied to other neurological disorders involving developmental gliogenesis/synaptogenesis abnormalities.

UMR 1334 AGAP : Equipe AFEF 'Architecture et Fonctionnement des Espèces fruitières' ; Team AFFS 'Architecture and Functioning of Fruit Species' Contact: valerie.pujade-renaud@cirad.fr; Corynespora Leaf Fall (CLF) is a major disease of rubber tree (Hevea brasiliensis) caused by the Ascomycota Corynespora cassiicola. Here we describe the cloning and characterization of a gene encoding cassiicolin (Cas), a glycosylated cystein-rich small secreted protein (SSP) identified as a potential CLF disease effector in rubber tree. Three isolates with contrasted levels of aggressiveness were analyzed comparatively. The cassiicolin gene was detected - and the toxin successfully purified - from the isolates with high and medium aggressiveness (CCP and CCAM3 respectively) but not from the isolate with the lowest aggressiveness (CCAM1), suggesting the existence of a different disease effector in the later. CCP and CCAM3 carried strictly identical cassiicolin genes and produced toxins of identical mass, as evidence by mass spectrometry analysis, thus suggesting conserved post-translational modifications in addition to sequence identity. The differences in aggressiveness between CCP and CCAM3 may be attributed to differences in cassiicolin transcript levels rather than qualitative variations in cassiicolin structure. Cassiicolin may play an important role in the early phase of infection since a peak of cassiicolin transcripts occurred in 1 or 2 days after inoculation (before the occurrence of the first symptoms), in both the tolerant and the susceptible cultivars.

International audience; A set of 41 wheat microsatellite markers (WMS), giving 42 polymorphic loci (two loci on each chromosome), was used to describe genetic diversity in a sample of 559 French bread wheat accessions (landraces and registered varieties) cultivated between 1800 and 2000. A total of 609 alleles were detected. Allele number per locus ranged from 3 to 28, with a mean allele number of 14.5. On the average, about 72% of the total number of alleles were observed with a frequency of less than 5% and were considered to be rare alleles. WMS markers used showed different levels of gene diversity: the highest PIC value occurred in the B genome (0.686) compared to 0.641 and 0.659 for the A and D genomes, respectively. When comparing landraces with registered varieties gathered in seven temporal groups, a cluster analysis based on an F(st) matrix provided a clear separation of landraces from the seven variety groups, while a shift was observed between varieties registered before and after 1970. There was a decrease of about 25% in allelic richness between landraces and varieties. In contrast, when considering only registered varieties, changes in diversity related to temporal trends appeared more qualitative than quantitative, except at the end of the 1960s, when a bottleneck might have occurred. New varieties appear to be increasingly similar to each other in relation to allelic composition, while differences between landraces are more and more pronounced over time. Finally, considering a sub-sample of 193 varieties representative of breeding material selected during the twentieth century by the six most important plant breeding companies, few differences in diversity were observed between the different breeding programmes. The observed structure of diversity in French bread wheat collections is discussed in terms of consequences, both for plant breeders and for managers of crop genetic resources.

New Comers and less favoured Areas : some Samples in the Massif central. After decades of rural drift, rural spaces today are going through a new demographic dynamism, even all the rural spaces are not concerned by this trend. An important part of the Massif central goes on losing inhabitants because of a natural persisting deficit and the continuous emigration of the young people under twenty five. Here and there, however, the arrival of a new population can be observed. Given the stake that they represent for the future of far-from great cities rural areas, it seems relevant to make a survey to know better the population of new comers and to define the strategies of the areas in front of the new populations' arrival. From the work done on six rural areas in the Auvergne and the Limousin, the article presents these new population's characteristics and their itinerary and tries to interpret the differences in attractiveness among these areas., Après des décennies d'exode, l'espace rural connaît aujourd'hui de nouvelles dynamiques démographiques. Tous les espaces ruraux ne sont cependant pas concernés par ces tendances : ainsi une grande partie du Massif central continue de perdre des habitants du fait d'un déficit naturel persistant et d'un départ continu de jeunes de moins de 25 ans hors région. Ici et là, cependant, on constate l'arrivée de nouvelles populations. Considérant l'enjeu qu'elles représentent pour le devenir d'espaces ruraux éloignés des grandes villes, il a paru pertinent de conduire une étude pour mieux connaître la population des nouveaux venus et les stratégies des territoires face à l'accueil de nouvelles populations. L'article présente, à partir des travaux conduits sur six territoires ruraux d'Auvergne et du Limousin, les caractéristiques de ces nouvelles populations ainsi que leur itinéraire migratoire, et tente d'interpréter les différences d'attractivité entre territoires., Mamdy Jean-François, Roussel Véronique. Nouveaux arrivants et territoires ruraux fragiles : quelques exemples dans le Massif central. In: Espace, populations, sociétés, 2001-1-2. Repopulation et mobilités rurales. pp. 109-122.

L’histoire de l’education des Sourds montre que l’enseignement en langue des signes dans un objectif bilingue ne date pas de notre siecle. Le bilinguisme est toujours percu comme dangereux pour l’acquisition de la langue francaise par les enfants sourds. Il y a presque trente ans, des projets bilingues ont vu le jour, certains existent encore, mais trois sur quatre n’ont jamais recu l’accreditation de l’Education nationale. Pire le systeme educatif remet au gout du jour des dispositifs drainant des methodes qui devraient legitimement avoir disparu, eu egard a la loi 2005, reconnaissant la LSF comme langue a part entiere dans le choix parental. Cet article tente de faire s’interroger sur la conception du bilinguisme et ses applications dans un systeme sense respecter le choix des familles d’enfants sourds.