NCAM1, also known as CD56, is a neural adhesion protein (NCAM) which belongs to the immunoglobulin superfamily. NCAM is involved in neural development and in plasticity in the adult brain. UCHL1 is a novel interaction partner of both NCAM isoforms that regulates their ubiquitination and intracellular trafficking. NCAM1 is a cell adhesion molecule involved in neuron-neuron adhesion, neurite fasciculation, outgrowth of neurites, etc. NCAM1 has also been shown to be involved in the expansion of T cells and dendritic cells which play an important role in immune surveillance.