Agrin is a multidomain heparan sulphate proteoglycan, that is a key organizer for the induction of postsynaptic specialisations at the neuromuscular junction. Binding of agrin to basement membranes requires the amino terminal (NtA) domain. This region mediates high affinity interaction with the coiled-coil domain of laminins. The binding of agrin to laminins via the NtA domain is subject to tissue-specific regulation. The NtA domain-containing form of agrin is expressed in non-neuronal cells or in neurons that project to non-neuronal cell such as motor neurons. The structure of this domain is an OB-fold.