Die Fakultät für Chemie und die Gesellschaft Deutscher Chemiker gemeinsam mit SFB 613: Physik von Einzelmolekülprozessen und molekularer Erkennung in organischen Systemen International Graduate School of Chemistry and Biochemistry laden ein zum Vortrag von Carsten Schultz, PhD European Molecule Biology Laboratory (EMBL) Heidelberg “New Molecular Tools Give New Insight in Cell Signaling” Our group is interested in better understanding intracellular signaling pathways. We therefore develop tools to visualize and manipulate signaling events in living cells. In this respect, lipids are one of the least investigated groups of biomolecules. We therefore synthesized membrane-permeant derivatives of various phosphoinositides to study growth factor receptor signaling. We find that the compounds stimulate signaling events downstream of PI 3-kinase in living cells. This leads to alterations in cell behavior, for instance in PC12 cell differentiation and neurite formation. In addition, some of the compounds are the first small molecules known to induce growth factor receptor endocytosis. Finally, we developed a novel method to visualize the formation of enzyme-substrate (ES) complexes in living cells. For this purpose, we synthesized artificial phosphorylated peptides that serve as substrates for one of the phosphatases that limit receptor tyrosine kinase activity, phosphotyrosine phosphatase 1B. By imaging the distribution of ES complex formation with spatial resolution, we demonstrated that the enzyme activity was predominantly located at internal membranes, while the enzyme seemed less active at the plasma membrane (Yudushkin et al, Science 2007). Universitätsgebäude, Hörsaal 3, Donnerstag, den 10. April 2008 um 17 Uhr c.t. gez. Prof. Dr. Thomas Koop, Prof. Dr. Uwe Manthe, Prof. Dr. Jochen Mattay