Alzheimer

Characteristic of Alzheimer´s disease is the accumulation of amyloid plaques in the brain. The major components of these plaques are 39-42 residue-long amyloid-β-peptides, which form insoluble fibrils via self-assembly. The amyloid-β-peptides are fragments of the broadly distributed, membrane-bound amyloid precursor protein APP, encoded on chromosome 21. They are formed from the proteolytic cleavage of APP by β- and γ-secretases.
Cleavage occurs after residue 40 or after residue 42. Even slightly increased amounts of amyloid-β-1-42 are described to be sufficient to cause Alzheimer's disease.
References:
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