Calsyntenin-1 also known as alcadein-alpha, CLSTN1 is a member of the calsyntenin family, a subset of the cadherin superfamily. Calsyntenin-1 is a proteolytically processed postsynaptic membrane protein with a cytoplasmic calcium-binding domain. By binding Ca2+, Calsyntenin-1 may modulate Ca2+-mediated postsynaptic signals. Calsyntenin-1 is thought to bind to kinesin-1 motors to mediate the axonal anterograde transport of certain types of vesicle. Amyloid precursor protein (APP) is trafficked via these vesicles and so this protein is being investigated to see how it might contribute to the mechanisms underlying Alzheimer's disease.