Rat Neural Cell Adhesion Molecule 1 / CD56 (NCAM1) Protein

Background

Neural Cell Adhesion Molecule 1 (NCAM1), also known as CD56, is a member of the immunoglobulin (Ig) superfamily and plays a critical role in cell-cell adhesion, neuronal development, and synaptic plasticity. NCAM1 is a transmembrane glycoprotein with alternative splice variants and glycosylation modifications, including polysialic acid (PSA) attachment, which regulates its function. Structurally, NCAM1 consists of five extracellular Ig-like domains, two fibronectin type III domains, a transmembrane domain, and a cytoplasmic tail involved in intracellular signaling. NCAM1 is highly expressed in the nervous system, where it facilitates neuronal migration, axonal growth, and the formation of synaptic connections during development. PSA-modified NCAM1 reduces adhesion and promotes neuronal plasticity. In adults, NCAM1 continues to regulate synapse maintenance, memory formation, and neuroregeneration. It is also expressed in other cell types, including natural killer (NK) cells, where it mediates immune recognition.