ISOLATION AND CHARACTERIZATION OF APLP2 ENCODING A HOMOLOG OF THE ALZHEIMERS ASSOCIATED AMYLOID BETA-PROTEIN PRECURSOR

Familial Alzheimer's disease (FAD) is a genetically heterogeneous diso rder that includes a rare early-onset form linked to mutations in the amyloid b protein precursor (APP) gene. Clues to the function of APP d erive from the recent finding that it is a member of a highly conserve d protein family that includes the mammalian amyloid precursor-like pr otein (APLP1) gene which maps to the same general region of human chro mosome 19 linked to late-onset FAD. Here we report the isolation of th e human APLP2 gene. We show that APLP2 is a close relative of APP and exhibits a very similar pattern of expression in the brain and through out the body. Like APP, APLP2 contains a cytoplasmic domain predicted to couple with the GTP-binding protein G(o) indicating that it may be an additional cell surface activator of this G protein.