Amyloids are self-assembled fibrous cross-beta protein aggregates, associated with a variety of human diseases and implicated in some positive biological functions. We have developed a new yeast-based experimental assay for identification of amyloidogenic proteins, and applied this assay to human proteins, that contain cross-beta structures as predicted by in silico algorithm ArchCandy. Our data confirm that at least some of these proteins indeed form amyloids. Specifically, some isoforms of the PHC3 protein, a member of chromatin-modifying complex PRC1, possess amyloidogenic properties. We propose that amyloid formation modulates the function of PRC1 in epigenetic regulation of chromatin. Our data provide a new strategy for identifying biologically important amyloids in human proteome.
Authors acknowledge support from RSF (14-50-00069) and from SPbSU Resource Centers “Development of Molecular and Cellular
Technologies” and “Biobank”.