It all sticks together - the APP-related family of proteins and Alzheimer's disease

in the present review, we shall discuss the pros and cons of a possible fun ctional relationship and contribution of the APP family members (APP, APLP1 and APLP2) to the development of Alzheimer's disease: (I) APP, APLP1 and A PLP2 are highly homologous proteins with similar protein domain organizatio n. (2) All APP family proteins have been found to be aggregated in typical Alzheimer's disease lesions. (3) Several other proteins have been Implied t o provide a functional link among the APP-related proteins. In normal adult brain APP, APLP1 and APLP2 are involved in synaptic processes important fo r memory function. We hypothesize that the functional loss of members of th e APP family contributes to the gradual cognitive decline in Alzheimer's di sease patients.