L1

L1 family consists of transmembrane five cell adhesion proteins (L1CAM, NgCAM-Related Cell Adhesion Molecule, Close Homologue of L1, Neural Cell Adhesion Molecule 1 and Neurofascin) that are expressed in axons and glia and are important for neural cell migration and maintenance during development and are key regulators of synapse formation. They belong to the Ig-superfamily of proteins and typically have six immunoglobulin-like and five fibronectin-type III domains. The L1-family interacts with multiple different synaptic cleft molecules, including fibroblast growth factor receptors, semaphorins and neuroligins. Interestinlgy, Neural Cell Adhesion Molecule can interact with AMPA-receptors through a poly-sialic acid (-2,8 linkage) modification on NCAM itself. (Unsure what the ligands are here…) ^{1 2 3}