KAINATE-BINDING PROTEINS - PHYLOGENY, STRUCTURES AND POSSIBLE FUNCTIONS

Recent advances have demonstrated that the family of [H-3]kainate-binding proteins and kainate receptors comprise a number of related polypeptides. In all the cases so far investigated, the kainate-binding proteins from nonmammalian vertebrates have Mr values in the range of 40-50 kDa whereas mammalian kainate receptors and kainate-binding proteins have Mr values in the order of 100 kDa. There have not, as yet, been any reports of 40-50 kDa kainate-binding proteins in mammalian CNS and, despite the cloning of increasing numbers of cDNAs encoding new kainate-binding proteins, the relationships between these two general groups of polypeptides remain unclear. Nonetheless, there is now a wealth of phylogenetic, structural and molecular biological data available about these proteins. In this review, Jeremy Henley outlines the properties and structures of kainate-binding proteins and offers some possibilities as to the roles of these often hugely abundant proteins.