Figure 1.

Amyloid formation and propagation at the molecular level. Native proteins oligomerize after adopting an abnormal β-sheet-rich fold, eventually forming a propagon. Propagons are specific units that can recruit and incorporate native monomers, which allows them to grow into amyloid fibrils. Fragmentation events can lead to complete depolymerization into monomers or to the formation of new propagons that in turn provide more ends for recruiting monomers.