Amyloid Precursor-like Proteins are members of the amyloid precursor protein (APP) superfamily of transmembrane proteins. APLPs show the same structural organization as APP, except APP contains a short Ab sequence associated with Alzheimerâs disease. All family members are proteolytically processed and appear to play a role in neurite outgrowth and copper metabolism. APLPs are proteolytically cleaved by MMPs and secretases, and form both homodimers and heterodimers with APP and other APLPs.
APLP-1 is expressed post-synaptically in cortical neurons. It functions as an adhesion protein through interactions with heparin and collagen I. APLP-1 can be cleaved by gamma-Secretase or Caspases to release intracellular fragments that activate transcription or enhance apoptosis, respectively.