Fig. 9
From: Alzheimer’s disease brain contains tau fractions with differential prion-like activities
Proposed working model of the prion-like propagation of tau. Abnormally aggregated tau forms O-tau, which recruits tau and templates its transformation. Inner aggregates of tau are compacted to form compressed NFTs, SI2-tau, in which the prion-like activities are passivated. Outer aggregates of tau, SI1-tau, on one hand recruit normal tau and template the transformation, resulting in the growth of the NFTs. On the other hand, these aggregates may be released to form O-tau, which seeds to form new aggregation in the cells or in new cells