MAPRE1 is a microtubule associated protein that interacts with the colorectal adenomatous polyposis coli tumor suppressor protein and plays important roles in regulating microtubule dynamics, cell polarity, and chromosome stability. This protein is related to MAPRE1 and likewise associates with the microtubule cytoskeleton. MAPRE3 is expressed predominantly in the central nervous system and preferentially associates with APCL, a homolog of the adenomatous polyposis coli tumor suppressor protein.