Structural investigation of membrane associated members of the bcl-2-proteinfamily, regulators of apoptosis

• Applicant: Matthias Michalek, Ph.D.
• Subject Area: Structural Biology
• Term: from 2010 to 2012
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 183543620

The bcl-2 proteinfamily plays a pivotal role in the regulation of controlled cell death. A defective regulation of apoptosis leads to cancer, autoimmunity reactions and neurodegenerative diseases. Several bcl-2 proteins insert into biological membranes, causing permeabilization due to pore formation, which is induced by a massive reorganization of their tertiary structure. Thereupon we are going to analyze the structures, topologies and dynamics of bcl-2 proteins in presence of lipid membranes and in interaction with each other. This work focuses the structural investigation of pro- and antiapoptotic Bcl-XL, Bcl-2 and Bax as well as derived fragments from these proteins in association with membranes. We propose techniques like recombinant expression, chemical solid-phase synthesis of peptides and their purification as well as isotopically labeling and solid-state NMR spectroscopy to analyze the protein-membrane and protein-protein interactions of bcl-2 members. Further experiments by ITC, DSC, ATR-IR, fluorescence and CD-spectroscopy will give additional information for this project. The structural details of membrane associated or interacting bcl-2 proteins in their monomeric, homooligomeric or pore-forming conformations will shed light on their regulative function in the process of apoptosis. Thereby dysfunctions leading to cancer will be revealed, providing insights into new strategies of early detection, damage limitation and combating cancer stages as well as other apoptosis-associated diseases.

• DFG Programme: Research Fellowships
• International Connection: France
• Host: Professor Dr. Burkhard Bechinger