Article

Truncated tau from sporadic Alzheimer's disease suffices to drive neurofibrillary degeneration in vivo.

Axon Neuroscience GmbH, Rennweg 95b, 1030 Vienna, Austria.
FEBS Letters (impact factor: 3.54). 07/2006; 580(15):3582-8. DOI:10.1016/j.febslet.2006.05.029 pp.3582-8
Source: PubMed

ABSTRACT Truncated tau protein is the characteristic feature of human sporadic Alzheimer's disease. We have identified truncated tau proteins conformationally different from normal healthy tau. Subpopulations of these structurally different tau species promoted abnormal microtubule assembly in vitro suggesting toxic gain of function. To validate pathological activity in vivo we expressed active form of human truncated tau protein as transgene, in the rat brain. Its neuronal expression led to the development of the neurofibrillary degeneration of Alzheimer's type. Furthermore, biochemical analysis of neurofibrillary changes revealed that massive sarcosyl insoluble tau complexes consisted of human Alzheimer's tau and endogenous rat tau in ratio 1:1 including characteristic Alzheimer's disease (AD)-specific proteins (A68). This work represents first insight into the possible causative role of truncated tau in AD neurofibrillary degeneration in vivo.

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Keywords

abnormal microtubule assembly
 
active form
 
AD neurofibrillary degeneration
 
biochemical analysis
 
characteristic Alzheimer's disease
 
characteristic feature
 
endogenous rat tau
 
first insight
 
human Alzheimer's tau
 
human sporadic Alzheimer's disease
 
human truncated tau protein
 
massive sarcosyl insoluble tau complexes
 
normal healthy tau
 
possible causative role
 
rat brain
 
structurally different tau species
 
truncated tau
 
Truncated tau protein
 
truncated tau proteins conformationally different
 
validate pathological activity