Figure 1.

α-Synuclein (αsyn) and the various conformations that can form upon misfolding. αsyn is a 14-kDa protein that contains several core regions and has seven imperfect KTKEGV repeats. In disease, monomeric protein aggregates, forming soluble misfolded oligomers. These oligomers can extend into protofibrils and mature species, such as fibrils or ribbons. Whereas there are limited studies on the biophysical properties of ribbons and their formation, the other misfolded structures exist in equilibrium with each other and can both expand and contract to higher- or lower-order conformations.