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Call for proposals: GENANIMAL 2006

Funding: ANR

Period: 2007-2010

Coordinator: Dr Florence Le Gac

Abstract

Our project in the long run aims at identifying transcriptional networks during a developmental process that is fundamental for species reproduction : gametogenesis. This is to be done in an aquaculture fish species : trout ; the physiological knowledge and the molecular tools we have contributed to producing are significantly favourable to such developments for that species.

Although the present project is focussed on fundamental aspects, it also entails future technological and societal applications : mastering the fertility and controlling the sexual maturation age in fish species are significant stakes for the competitiveness of aquaculture. Besides, using techniques that will prevent the reproduction of allochton or genetically selected aquaculture species do matter for the conservation of the environment.

Our immediate specific objectives are the analysis of genes involved in key stages of the spermatogenesis and/or in it's regulation using trout DNA chips. The use of microarrays produced in collaboration with the resource centre GADIE and the informatics' team SIGENAE and containing 9000 target cDNA allow large scale transcription studies ; we already have settled this technology in our laboratory and demonstrated the usefulness and feasibility of this approach on trout testis (Mazurais et al 2005). The involvement of 2 external teams (R Houlgatte, INSERM Nantes; M Primig Biozentrum Basel) with recognized expertise in bio-informatics applied to studies on transcriptome and on gametogenesis will provide us with new skills in fine gene annotation and data mining, necessary for optimum exploration of our own data and of the enormous amount of information contained in international data bases on genomes and gene function. This is specially true for an unconventional species like the trout as we have to rely on the complementarities of other model species. In particular, data obtained in the trout model will be compared to those obtained recently in rat and human spermatogenesis and in yeast meiosis using Affimetryx genechips. This comparison will allow to identify the core expression program that orchestrates spermatogenesis events across species and to concentrate our future efforts on genes with conserved function over evolution. Experimental and in silico studies will tell us about the regulation of these genes, in particular by sex steroid hormones. To demonstrate the relevance of genes selected in spermatogenesis onset and maintenance, we plane to produce transgenic fish lines for in vivo gene function analysis, first in zebrafish or medaka. Our first objective will be to isolate and validate DNA promoter fragments that drive high transgene expression levels specifically in Sertoli cells and germ cells.

The expected results will be interesting for scientists working in basic and applied research in fish reproduction, as well as researchers in the field of genome expression studies - either on other physiological functions, or in other species of agronomical interest-, that would benefit of new approaches and expertise in annotation methods, and in cross-species comparative studies with more documented animal models.

Partners

• Dr Florence Le Gac (Coordinator) - SCRIBE, INRA, UR1037 - Campus de Beaulieu - 35042 Rennes Cedex, France
• Dr Rémi Houlgatte - Institut du Thorax - INSERM U533 - 44035 Nantes cedex 1, France
• Prof. Bernard Jégou - GERHM - 35042 Rennes CEDEX, France
• Dr Jean-Jacques Lareyre - SCRIBE, INRA, UR1037 - 35042 Rennes Cedex, France
• Prof. Michael Primig - Biozentrum, University of Basel - CH-4056 Basel, Switzerland