hypervariable surfaces of each of the five LNS domains on one side of the molecule and reveals possible additional direct interaction from the LNS3 and/or LNS4 domain of NRXNα1 with NLGN (Fig. 1).TheoverlayshowstheboundNLGNto be adjacent to the LNS4 domain of NRXNα1, and the buried interface contains a flexible loop that includes the position for splice insert SSA