Neuronal cell surface protein that may be involved in cell recognition and cell adhesion. May mediate intracellular signaling (By similarity).
Subcellular locations: Presynaptic cell membrane
Expressed in the blood vessel walls (at protein level). Highly expressed in brain, lung, and pancreas; a lower level of expression is detectable in heart, placenta, liver, and kidney, whereas no expression can be observed in skeletal muscle. Isoform 4a is heart-specific.