Human L1CAM Antibody

L1CAM (Neural cell adhesion molecule L1, also known as L1, CD171 and NCAM-L1) is a 200-230 kDa member of the L1 family, Immunoglobulin (Ig) superfamily of molecules. L1 is recognized to play a key role in cell migration, adhesion, neurite outgrowth, myelination and neuronal differentiation. It does so through a series of cis and trans interactions that involve multiple copartners and target receptors. L1 is described as forming both homotypic and heterotypic complexes, the latter with molecules as diverse as the EGFR, NCAM, CD24, neurocan and various alpha v plus beta 1 and beta 3 integrins. Cells known to express L1 include immature oligodendrocytes, CD4+ T cells, B cells and monocytes, pre-myelinating Schwann cells, intestinal epithelial progenitor cells, and cerebellar granule plus Purkinje cells. Mature human L1 is a 1238 amino acid (aa) type I transmembrane protein. It contains an 1101 aa extracellular region (aa 20-1120) plus a 114 aa cytoplasmic domain (aa 1144-1257). In general, the full-length L1 molecule is a neuron-associated isoform. L1 is known to undergo proteolysis, either by plasmin or ADAMs. This generates soluble isoforms of varying sizes (140-200 kDa) that retain bioactivity, and which can be incorporated into the surrounding ECM. The membrane fragments (30-80 kDa) undergo further processing, most importantly by gamma-secretase, to generate a soluble 28 kDa intracellular domain. This domain is SUMOylated, and believed to possess an NLS at Lys1147. Upon presumed entry into the nucleus, L1 is posited to activate L1-responsive genes. In the extracellular region, human and mouse L1 share 86% aa sequence identity.