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Lighting Up the Pathways to Caspase Activation Using Bimolecular Fluorescence Complementation
Published on: March 5, 2018
Agonist mobility on supported lipid bilayers affects Fas mediated death response
M Florencia Sánchez1, Valeria Levi2, Thomas Weidemann3
1Instituto de Investigación Médica Mercedes y Martín Ferreyra (INIMEC), CONICET-Universidad Nacional de Córdoba, Friuli 2434, CC389, 5000 Córdoba, Argentina.
Abstract:
Extrinsic apoptosis is initiated by recognition and clustering of the single-pass transmembrane proteins Fas ligand and Fas expressed at the surface of closely apposed lymphocytes and target cells, respectively. Since Fas-mediated death response was mainly studied with soluble antibodies, the mobility constraints for receptor activation by a membrane embedded agonist is not well understood. We explored this influence by stimulating apoptosis on functionalized supported lipid bilayers, where we quantified agonist mobility by z-scan fluorescence correlation spectroscopy. Using different lipid compositions, we show that the apoptotic response correlates with increased lateral mobility of the agonist in the lipid bilayer.
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