Analyse Dynamique de l'Assemblage Macromoléculaire pendant le Contrôle de l'Expression Génétique – DAMAGE

The complex and dynamic network of interactions between cellular macromolecules plays an essential role in the regulation of important physiological behaviour in both prokaryotes and eukaryotes. The main aim of this project is to combine the expertise of three research groups, to further step into detailed characterization of interactions of important bacterial chromatin regulatory proteins with their interacting components including proteins and nucleic acid fragments. We will thus unravel the underlying mechanism of a major, if not the major, regulatory network for gene silencing in bacteria and thus open the possibility of elucidating the control of pathogenicity in a range of key microorganisms. The approaches used by the teams in the consortium are highly complementary. Partner 1 will bring its expertise in nucleoprotein complex formation in vivo to identify H-NS partners and in the kinetics of transcription initiation to investigate the action of the nucleoprotein complexes on target genes transcription initiation both in vitro. Partner 2 will extend the ground breaking observations made by her team concerning the mode of specific action of H-NS towards a deeper mechanistic analysis of H-NS regulation and also identify key partners in H-NS nucleoprotein complexes in vivo. Partner 2 will define model for H-NS specific nucleoprotein complex that can be validated. Partner 3 will validate their model for H-NS action in different, and especially plant pathogenic, strains thus providing an important model for developing drugs against pathogenic related diseases. Partner 3 will use plasmids bearing promoters of representative E. chrysanthemi gene(s) and the corresponding protein preparations to elucidate the mechanism of the regulators and to define the conditions that will be used by Partner 1 for the nucleoprotein complex characterization. Partner 3 will also use its expertise in genetic, biochemistry and molecular biology to functionally characterize the partners of H-NS and PecT. Partner 3 will provide partner 1 with the required strains, proteins and DNA templates for in vitro kinetic analysis of the formation of nucleoprotein complexes and the analysis of potential partners in specific nucleoprotein complexes.