Project 1: ApoE isoform-specific structure
Very little is known about the structure of apoE isoforms in the context of endogenously secreted lipoproteins. Project 1 aims to assess the conformational ensemble of apoE in its monomeric, oligomeric, and lipid-bound forms by using an innovative multipronged approach that combines single- molecule fluorescence spectroscopy and cryo- electron microscopy (EM). In collaboration with Core B, single-molecule measurements, negative-stain, and cryo-EM will be compared and interpolated with molecular dynamics simulations to reconstruct atomistic-detailed models of the protein when bound to secreted lipoproteins and AÎ². The proposed experiments will provide a detailed atomistic structural representation of apoE isoforms in the context of lipoproteins and while interacting with AÎ², integrating the biochemical characterization of Core B, and facilitating investigations of isoform-specific functional effects conducted by Projects 2-5 and Core B-F.