Sex determination and sexual differentiation in fish ("the sex of sturgeons")

L'esturgeon, de la famille des Acipenséridés, est un poisson ancestral, commercialement très intéressant et menacé d'extinction. Déjà élevé depuis plusieurs années pour la réintroduction dans le milieu et la production de caviar, des questions demeurent quant à son système de détermination du sexe. Nous avons entrepris d'en explorer la voie génétique, d'une part en recherchant le polymorphisme moléculaire par des approches de criblages aléatoires, d'autre part en étudiant l'expression du génome par une technique de criblage différentiel. SPAC,ME a été développé en réponse à des évolutions devant être opérées sur le logiciel SPAC créé précédemment. Une protéine peut désormais, grâce à son poids moléculaire et à sa composition en acides aminés, être identifiée parmi les données d'une banque protéique ou nucléique par le biais d'une requête plus complète et avec des résultats plus pertinents.The sturgeon, family of Acipenseridae, is an ancestral fish, commercially very interesting and threatened of extinction. Sturgeons are raised for reintroduction in their environment and for the caviar production. Questions have remained as for its system of sex determination. We undertook to explore the genetic way of it, on the one hand by seeking molecular polymorphism by approaches of random screening, on the other hand by studying the expression of the genome by a technique of differential screening, SPACNE was developed in response to evolutions having to be operated on software SPAC previously created. A protein can from now on, only with its molecular weight and its aminoacids composition, be identified among the data of a protein or nucleic bank by the means of a more complete request and with more relevant results.TOULON-BU Centrale (830622101) / SudocSudocFranceF

THE CUTTING EDGE OF ENDOCRINE DISRUPTING CHEMICALS IN FRESHWATER FISHES

International audienceIn recent decades, industrial, agricultural and urban waste has been discharged into rivers, streams, lakes and estuaries causing a considerable increase in pollution and the progressive degradation of freshwater ecosystems. The effluents from most cities and industrial plants contain a large variety of pollutants including polycyclic aromatic hydrocarbons (PAHs), surfactants and persistent organic pollutants (POPs). The twelve worst POPs defined by the Stockholm Convention have been clustered into three main classes: pesticides, industrial chemicals such as PCBs, and dioxin-like PCBs (PCDD/PCDF). These last compounds are responsible for high chronic toxicity, hydrophobicity, and are also well-known to interfere with endocrine systems; so called endocrine disrupting compounds (EDs). Even low concentrations of EDs in freshwater environments represent a significant threat to wildlife and ultimately to human health. In the present study, we investigate the impact of EDs in freshwater fishes and review the cutting edge of the principal molecular tools (biomarkers such as vitellogenin, cathepsin D, aromatase and spiggin) commonly used to assess their impact. Finally, we highlight examples of the growing contribution made by DNA microarray technology to ecotoxicology studies and monitoring

Output of liver fatty acid-binding protein (L-FABP) in bile.

International audienceLiver fatty acid-binding protein (L-FABP) is a small cytoplasmic molecule highly expressed in the liver. Since L-FABP exhibits affinities for several biliary components, its presence in bile was explored by Western blotting and competitive ELISA in various mammalian species. A L-FABP-like immunoreactivity was consistently found in both hepatic and gallbladder bile. A close molecular identity between this 14 kDa biliary protein and the purified L-FABP was assessed by immunological analyses and high performance capillary electrophoresis. Pharmacological induction of hepatic L-FABP biosynthesis led to a similar increase in biliary L-FABP levels showing a close relationships between the cytosolic and biliary contents of this protein. Finally, a correlation between the presence of L-FABP in bile and both bile flow and bile acid release was found. These data suggest an output of L-FABP in bile in normal conditions which might be coupled with the physiological release of biliary components

Grouper aquaculture: Asian success and Mediterranean trials

International audienc

THE CUTTING EDGE OF ENDOCRINE DISRUPTING CHEMICALS IN FRESHWATER FISHES

International audienceIn recent decades, industrial, agricultural and urban waste has been discharged into rivers, streams, lakes and estuaries causing a considerable increase in pollution and the progressive degradation of freshwater ecosystems. The effluents from most cities and industrial plants contain a large variety of pollutants including polycyclic aromatic hydrocarbons (PAHs), surfactants and persistent organic pollutants (POPs). The twelve worst POPs defined by the Stockholm Convention have been clustered into three main classes: pesticides, industrial chemicals such as PCBs, and dioxin-like PCBs (PCDD/PCDF). These last compounds are responsible for high chronic toxicity, hydrophobicity, and are also well-known to interfere with endocrine systems; so called endocrine disrupting compounds (EDs). Even low concentrations of EDs in freshwater environments represent a significant threat to wildlife and ultimately to human health. In the present study, we investigate the impact of EDs in freshwater fishes and review the cutting edge of the principal molecular tools (biomarkers such as vitellogenin, cathepsin D, aromatase and spiggin) commonly used to assess their impact. Finally, we highlight examples of the growing contribution made by DNA microarray technology to ecotoxicology studies and monitoring