Polymorphism of Tau Fibrils

Tau is a protein that binds and stabilizes microtubules as a physiologic function, but it is also well known as a protein that forms insoluble and fibrillar aggregates in neurodegenerative diseases called tauopathies. Notably, pathologic Tau fibrils exhibit various morphologies that are associated with particular subtypes of tauopathies. Distinct symptoms among tauopathies could thus be regulated by the morphology/structure of Tau fibrils, but the exact mechanism by which such polymorphism arises in Tau fibrils remains unknown. In this chapter, to help the reader understand possible roles of polymorphic Tau fibrils in the pathomechanism of neurodegenerative diseases, I review and summarize several factors affecting the morphologies of Tau fibrils in vitro.