Description:
The traditional view of the lipid bilayer described as a sea of lipids where proteins may float freely, is increasingly recognized as being inadequate when used to describe the large number of complex phenomena that takes place in biological membranes. Membrane-assisted protein-protein interactions, formation of lipid clusters, protein-induced variation of the membrane curvature, abnormal membrane permeability and conformational transitions of membrane-embedded proteins are only a few examples of the variegated ensemble of events whose tightly regulated cross-talk is essential for cell structure and function. Many proteins involved in misfolding-based pathologies are membrane-associated and therefore the bilayer may play different roles in normal and aberrant folding. In the present activity we test the generality of these concepts on several systems, i. e. prion peptides, amylin, A? amyloid and VEGF. In particular, we are interested in addressing the role of (adverse) environmental factors such as pH and metal ions in driving protein conformations and/or protein protein interactions in a lipid environment. The ability of small-sized protein assemblies to affect membrane integrity and their eventual cytotoxicity are also the targets of our research. An array of different experimental (Circular Dichroism, NMR, Differential Scanning Calorimetry and Fluorimetry) and computational (Molecular Dynamics) techniques is used in our labs to shed light on all these issues