Protein Amyloidogenesis Investigated by Small Angle Scattering

In the last decades, the study of the mechanisms inducing amyloid fibril formation has involved several experimental and theoretical biophysical approaches. Many efforts have been made by scientist at the borderline between biology, chemistry, biochemistry and physics in order to understand why and in which way a protein starts its amyloidogenic pattern. This fundamental research issue is evolving in parallel to the development of drugs and inhibitors able to modify protein self assembly towards amyloid fibrils. Small angle xray and neutron scattering experiments represent suitable methods to investigate protein amyloidogenesis and the possible effects of inhibitors: they are in-solution techniques, require low amount of sample and their time-resolution makes it possible to follow aggregation pattern. In this paper we review small angle x-ray and neutron scattering studies dedicated to investigate amyloid β peptide and α-synuclein, related to Alzheimer's and Parkinson's diseases, respectively, together with some other studies that introduced innovative models to describe with small angle scattering techniques amyloid fibrillation processes. Keywords: Amyloid, synuclein, SAXS, SANS, scattering, self-assembly.