ABSTRACT
Most neural members of the immunoglobulin superfamily (IgSF) are large multi-domain proteins that undergo multiple complex molecular interactions with other axonal Ig-like proteins and/or glycoproteins of the extracellular matrix (ECM). They might be therefore components of a complex network of interacting recognition molecules. This chapter focuses on binding studies and on analyses of the molecular basis of neurite outgrowth mediated by adhesion receptors of the IgSF. Three common themes are emerging from these studies. First, the regions within these molecules which mediate molecular interactions are frequently localized in their aminoproximal domains. Second, the binding of neural IgSF molecules to their ligands and receptors is highly promiscuous. Third, only some of the interactions identified and analysed using in vitro binding assays could also be demonstrated to be involved in the induction of neurite outgrowth.
