Background

The amyloid precursor protein (APP) is a type I trans-membrane protein that is expressed in a wide number of different cell types. Proteolytic processing by beta-and gamma-secretases releases 38-43 amino acid long peptides, so called Ab amyloid peptides that accumulate within the plaques in the brain of Alzheimer´s disease patients. Alternatively, initiation of the proteolysis cas-cade by alpha-secretase prevents the development of these toxic peptides [1,2]. In spite of intense research regarding the involvement of APP in Alzheimer´s disease, The three-dimensional structure of the entire protein, its physiologic function and the regulation of its proteolytic processing remain, however, largely unclear to date [3]. Materials and method