Preparation of mouse and human α-synuclein fibrils v1

This protocol describes the preparation of homogeneous a-synuclein fibrils. The primary objective is to generate alpha-synuclein fibrils with high homogeneity in size, devoid of other protein species such as monomers and oligomers. The protocol employs shaking to generate the fibrils and sonication to reduce the fibrils to their terminal length. The expected outcome is the production of highly homogeneous fibrils, with a consistent size range of 25±5 nm in radius, and at high concentrations without the presence of monomers and oligomers. This protocol provides a method for producing stable, homogeneous sonicated fibrils that can be stored in batches for in vitro and in vivo experiments. By following this protocol, the fibrils produced will consistently maintain the same size and concentration, thereby ensuring the reliability and reproducibility of subsequent experimental results.