Determination of the properties of receptor subtypes comprised of different combinations of NR1 splice variants and NR2 subunits has been a recent theme of our work. Site directed mutagenesis is being used in structure-function studies and has identified amino acid residues that are critical for agonist affinity and potentiation by spermine, PCP and zinc. Sites of phosphorylation and potentiation by protein kinase C are also under investigation. Studies of gap junction mediated communication include phylogenetic analyses that have identified regions of conservation and variation in connexins. Conserved regions must represent functionally important regions in common.
Divergent regions account for functional differences or are neutral.
Identification of connexin types expressed in different tissues and analysis of functional differences is proceeding. The phenotype is a demyelinating peripheral neuropathy, generally with onset in late childhood. In other studies the role of gap junctions in CNS functions including communication between astrocytes is being investigated. AMPA recep-tors in delayed neurodegeneration. Cold Spring Harbor Symp.