SYN1, also named as Brain protein 4.1, belongs to the synapsin family. SYN1 is a neuronal phosphoprotein that coats synaptic vesicles, binds to the cytoskeleton, and is believed to function in the regulation of neurotransmitter release. The complex formed with NOS1 and CAPON proteins is necessary for specific nitric-oxid functions at a presynaptic level. Defects in SYN1 are a cause of epilepsy X-linked with variable learning disabilities and behavior disorders (XELBD). The antibody is special to SYN1.