1. Departamento de Química Biológica Ranwell Caputto, Facultad de Ciencias Químicas, CIQUIBIC‐CONICET‐Universidad Nacional de Córdoba, Córdoba, Argentina;2. Laboratorio Neurobiología, Instituto Investigación Médica Mercedes y Martín Ferreyra, INIMEC‐CONICET‐Universidad Nacional de Córdoba, Córdoba, Argentina;3. Instituto Universitario Ciencias Biomédicas Córdoba, Córdoba, Argentina;4. Axonal Growth and Regeneration, German Center for Neurodegenarative Diseases, Bonn, Germany;5. Laboratorio de Neuropatología Experimental, Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC‐CONICET‐Universidad Nacional de Córdoba, Córdoba, Argentina
Abstract:
The amyloid precursor protein (APP) is a type I transmembrane glycoprotein better known for its participation in the physiopathology of Alzheimer disease as the source of the beta amyloid fragment. However, the physiological functions of the full length protein and its proteolytic fragments have remained elusive. APP was first described as a cell‐surface receptor; nevertheless, increasing evidence highlighted APP as a cell adhesion molecule. In this review, we will focus on the current knowledge of the physiological role of APP as a cell adhesion molecule and its involvement in key events of neuronal development, such as migration, neurite outgrowth, growth cone pathfinding, and synaptogenesis. Finally, since APP is over‐expressed in Down syndrome individuals because of the extra copy of chromosome 21, in the last section of the review, we discuss the potential contribution of APP to the neuronal and synaptic defects described in this genetic condition.
