ALPP is a membrane protein and exits as a homodimer. ALPP is expressed only in normal term placenta, endocervix and fallopian tube and also in ovarian and proximal gastrointestinal tumors. It has been shown to play a role in a number of processes including cell signaling, long-term potentiation, and cell adhesion, however, the best known and most commonly studied role is implicated in Alzheimer's research.