Calendar Name: seminars Scheduled for: Tuesday, September 21 2010, 15:00 - 16:30 Event text: Toshihiro Obata Max-Planck-Institute f�r Molecular Plant Physiology Potsdam-Golm GERMANY Details: "Metabolic response to oxidative stress in Arabidopsis" ABSTRACT Plants must reconfigure their metabolic network under stress conditions to prevent the accumulation of reactive oxygen species (ROS) and to produce indispensable metabolites. We have investigated the response of Arabidopsis roots to menadione-induced oxidative stress by means of metabolite profiling and transcriptome analysis. The results suggested the importance of mitochondrial metabolism in stress response and also highlighted a complex relationship between the levels of transcripts, metabolites, and metabolic flux. We hypothesise the reassembly of enzyme protein complexes as a molecular mechanism of mitochondrial metabolic regulation. A proteomic approach using blue-native/SDS-PAGE revealed that some mitochondrial enzymes associated to or dissociated from a protein complex under oxidative stress. These results suggest the regulation of the TCA cycle, glycolysis, ascorbate and amino acid metabolism under oxidative stress by reassembly of enzyme supercomplexes.