Key Physicochemical and Biological Factors of the Phase Behavior of Tau

Abstract

Recent findings have garnered a substantial amount of attention toward tau based on its pathological contribution to neurodegenerative diseases, such as Alzheimer's disease (AD). Studies investigating the structure and aggregation of tau under various in vitro and in vivo conditions have revealed its intrinsically disordered structures and amyloidogenesis process. The aggregation behavior of tau is strongly dependent on the experimental conditions due to the high sensitivity of both the soluble tau conformations and the amyloid nucleation process toward its surrounding environments. Herein, we review and discuss (1) the effects of different physicochemical and biological factors as well as intermolecular interactions with various molecular chaperones on tau aggregation, (2) context-dependent liquid-liquid phase separation of tau and its amyloidogenic transformation, and (3) the utility of the phase diagram in comprehending the phase transition and separation of proteins.