CD56 Antigen

**Semantic type:** Amino Acid, Peptide, or Protein|Neuroreactive Substance or Biogenic Amine

**Definition:** Neural Cell Adhesion Molecule is a membrane-bound glycoprotein member of the Ig superfamily that binds to a variety of other cell adhesion proteins involved in diverse contact-mediated interactions. NCAM appears on early embryonic cells and is important in the formation of cell collectives at sites of morphogenesis. Later it is found on differentiated neurons, astrocytes, oligodendrocytes, and myotubes and mediates neuronal adhesion, guidance, and differentiation. NCAM plays a role in cell-cell and cell-matrix adhesion through homophilic and heterophilic binding. The invertebrate cell adhesion molecules fasciclin II (grasshoppers and Drosophila) and apCAM (Aplysia) are related to NCAM and can mediate homophilic cell aggregation. Four main isoforms exist, including CD56, but many variants result from alternative splicing and post-translational modifications. (from OMIM 116930 and NCI)

**Synonyms:** - CD56 - NCAM - NKH-1 - Neural Cell Adhesion Molecule