Hyperphosphorylation of tau is one of the earlier events in the formation of neurofibrillary tangles. Recent studies provide interesting information concerning the course of tau pathology in relation to amyloid pathology in the 3×Tg-AD mice (Oddo et al., 2003) and shed new light on the pathological effects of tau hyperphosphorylation and aggregation (Santacruz et al., 2005; Binder et al., 2005). Functional implications of hyperphosphorylation of tau may be far-reaching when it comes to developing neural progenitor cells, affecting mitosis, axonal transport, process elongation and neuronal maturation [For review see (Johnson and Stoothoff, 2004)].
