Floating mitochondrial membrane mimics for investigating apoptosis regulating protein interactions

Mitochondrial apoptosis is a programmed suicide mechanism in cells essential for life. Upon oxidative stress, the mitochondrial outer membrane (MOM) undergoes permeabilization, followed by the release of apoptotic factors. This process is tightly regulated by the Bcl-2 protein family at the MOM. In healthy cells, the soluble, pro-apoptitic Bax is neutralized by the anti-apoptotic Bcl-2 embedded in the MOM, but any imbalance in this interaction can cause disorders including cancer. We are using neutron reflectometry to elucidate the function of the Bcl-2 protein family in supported lipid bilayers. In this experiment we will self-assemble floating bilayers from lipid extracts purified from yeast cells that match the human MOM composition closely, to investigate the pore-formation mechanism of Bax and role of cardiolipin in more realistic mimics of the MOM with an aqueous reservoir on both sides as in mitochondria.