In vitro polymerization of oxidized tau into filaments.

Paired helical filaments (PHF) are abnormal neuronal polymers characteristic of Alzheimer's disease (AD). Although tau appears to be a major constituent of PHF, the mechanism for the polymerization of tau or its integration into PHF remains unknown. Here, we show that the oxidation of bovine tau in vitro induces an apparent dimerization of this protein and polymerization into filaments. These observations suggest that the oxidation of tau in vivo may contribute to the development of PHF in individuals with AD.