Selective interaction of amyloid precursor protein with different isoforms of neural cell adhesion molecule.

Compare to the thoroughly studied beta-amyloid, the physiological function of amyloid precursor protein (APP) is not well understood. We now had identified neural cell adhesion molecule (NCAM)-140 as a potential interaction partner of APP. Our data indicated that NCAM-140, but not NCAM-180, binds to the conserved central extracellular domain of APP. We also found that the phosphorylation levels of ERK1 and ERK2 were increased when cells were co-transfected with NCAM-140 and APP indicate that the interaction between NCAM-140 and APP may involve the MAPK pathway. These findings demonstrated that NCAM-140 interacts with APP, potentially playing a role in neurite outgrowth and neural development.