Delta Receptors

Abstract

No endogenous ligands have been identified for the delta subfamily of ionotropic glutamate receptors (GluR1 and GluR2). Nevertheless, GluR2 plays indispensable roles in cerebellar functions; mice that lack the GluR2 gene display ataxia and impaired motor-related learning tasks. Recent studies of mutant mice, such as lurcher, hotfoot, and GluR2-knockout mice, have provided clues to the structure and function of GluR2. In particular, morphologic and electrophysiologic analyses of hotfoot and GluR2-knockout mice have demonstrated a unique role of GluR2 in synapse formation and its maintenance. In addition, an antibody specific for GluR2's extracellular N-terminal indicated its direct role in controlling cerebellar long-term depression. These results suggest that GluR2 regulates distinct s pathways involved in synapse formation and synaptic plasticity.