Amyloid Precursor Protein β, Secreted human

Amyloid-β (Aβ) peptides are a major component of the senile plaques characteristic of the Alzheimer brain. It is a type- I transmembrane protein. The gene encoding amyloid-β is localized on human chromosome 21.

Human amyloid precursor protein β has been used as peptide standard.

The secreted amyloid precursor β (sAPPβ) is a proteolytic cleavage product of β amyloid precursor protein (APP). APP is cleaved by β-secretase into two fragments, sAPPβ and β-amyloid peptide (Aβ). The Aβ is a component of amyloid plaques, one of the major hallmarks of Alzheimer`s disease (AD), while the sAPPβ is thought to modulate neuronal function and cell survival. Mutation in APP found in Swedish familial AD pedigree increases the susceptibility of APP to β-secretase cleavage and the formation of Aβ and sAPPβ. In contrast, activation of protein kinase C (PKC) decreases the levels of sAPPβ. The trans-Golgi network (TGN) is the major site for β-secretase activity.

0.2 μm filtered solution in 20 mM Tris (pH 7.4), 0.5 M NaCl, 1 mM EDTA, 5 mM βME, 2 μg/ml aprotinin

sAPPβ was expressed in E. coli as a soluble protein and purified under non-denaturing conditions