Signaling Pathways Involved in NCAM-Induced Neurite Outgrowth

The neural cell adhesion molecule, NCAM, plays important roles in both the developing and adult brains. NCAM, originally, was described as a homophilic cell adhesion molecule abundantly expressed in the central nervous system. This view has been challenged, however, during the last two decades, and NCAM now is considered to be an inducer of complex intracellular signaling cascades in response to extracellular cues. Homo and heterophilic NCAM interactions result in the induction of neurite outgrowth, neuronal survival, and astrocyte proliferation. Here, we review the available data regarding NCAM-induced intracellular signaling and focus on the most intensively studied cellular response, neurite outgrowth.