Cell adhesion molecule that plays a role in neuronal self-avoidance (PubMed:11453658). Promotes repulsion between specific neuronal processes of either the same cell or the same subtype of cells. Promotes both isoneuronal self-avoidance for creating an orderly neurite arborization in retinal rod bipolar cells and heteroneuronal self-avoidance to maintain mosaic spacing between AII amacrine cells (By similarity). Adhesion molecule that promotes lamina-specific synaptic connections in the retina: expressed in specific subsets of interneurons and retinal ganglion cells (RGCs) and promotes synaptic connectivity via homophilic interactions (By similarity). Homodimer; mediates homophilic interactions to promote cell adhesion. Detected in heart, liver, pancreas, skeletal muscle, kidney and in brain, in particular in the amygdala, caudate nucleus, corpus callosum, hippocampus, substantia nigra, thalamus and subthalamus. Extended N-terminus. Aberrant splice donor site. Extended N-terminus.