[BK21 Plus Seminar]
        
          
       ▶Subject: ErbB signaling - Quantification of protein diffusion and interaction networks in MCF7 cells using fluorescence correlation method
                   
       ▶Speaker: Chan-Gi Pack, Ph.D. (University of Ulsan College of Medicine, Asan Medical Center)

                                 
       ▶Date: 11:00AM/Jan/30(Fri)/2015
                
       ▶Place: Conference Room(#179), Postech Biotech Center

                      
              *Abctract
            The signaling pathway of ErbB receptors including ErbB1 - 4 is involved in diverse physiological processes such as cell proliferation, differentiation, apoptosis, and carcinogenesis. Systems-level analyses have been recently carried out for this pathway, combining conventional biochemical methods in vitro with computational simulation. However, information about spatiotemporal dynamics and reaction-kinetics of related proteins are largely lacking. It will be worthwhile to directly quantify localization, diffusion, and interaction of related proteins in living cells.
We have established a live cell fluorescence correlation spectroscopy (FCS/FCCS) and single molecule (SM) analysis of the proteins in the ErbB networks. We focused on the quantification of diffusions and interaction of Shc52, Grb2, and PI3Ks (p85 and p110) which are major cofactors for EGF (ErbB1/EGFR ligand) and HRG (ErbB3, 4 ligand) signaling process. Analysis using MCF7 and its mutant cells lines overexpressing ErbB1 indicates that diffusional movements (response) of these cofactors were differently changed depending on the cell types and ligands. Interestingly, direct interactions among them, especially between Shc and Grb2, were not found in live cell measurements, even though interactions with ErbBs were detected for all the factors. These results suggest that spatiotemporal response of these factors with ErbB receptors are independently regulated in living cells, even details of the response and interaction among cofactors have not been described until now. Our study will pave the way toward a new insight for ErbB signaling mechanism at a system level

       ▶Inquiry: Prof. Ryu, Sung Ho(279-2292)
              
        
        * This seminar will be given in English