Drosophila Appl Gene and APPL Protein: A Model System to Study the Function of the APP Protein Family

Drosophila Amyloid precursor protein-like (Appl) gene encodes a protein product, APPL, similar to the β-amyloid precursor protein (APP) associated with Alzheimer’s disease. The Drosophila APPL protein is neural-specific and is first detected in developing neurons concomitant with axonogenesis. APPL immunoreactivity is observed in neuronal cell bodies and in axons of both immature and mature neurons. Similar to APP, APPL is synthesized as a membrane-associated glycosylated precursor protein that is rapidly converted into a secreted form that lacks the cytoplasmic domain.