Glutamateis recognized as being the most important excitatory neurotransmitter in the brain, transmitting information between nerve cells by activating AMPA- and NMDA type glutamate receptors (AMPARs and NMDARs) present at synapses. My lab focuses on understanding how glutamate receptors, their constituent subunits and associated molecules, shape fast synaptic transmission at individual synapses and in specific neural circuits. Early studies on ligand gated-channels suggested that neurotransmitters activate receptors with homogeneous channel properties. However, an altogether more versatile picture has emerged from work on mammalian central synapses. Comparison of different types of neurons has shown that they possess distinct complements of mRNAs coding for the various glutamate receptor subunits. The discovery of functional heterogeneity in glutamate receptor-channel properties is starting to explain one of the major issues in our understanding of central synaptic transmission - namely, how a single transmitter generates such enormous diversity in signalling between nerve cells, and within neural circuits. It is therefore a major challenge to understand precisely how individual receptor subunits influence basic properties of transmission at specific synapses, and how subunit diversity enables various dynamic changes in synaptic function. This is an essential step towards the understanding of signalling in the brain.The properties of AMPAR receptors are determined by their constituent building blocks (subunits). AMPAR subunit composition is thus critical in shaping fast excitatory synaptic transmission, and neuronal circuit behaviour. Of the AMPAR subunits, we are particularly interested in GluR2. This subunit is subject to posttranscriptional RNA editing which results in a single amino acid switch in its pore lining region. Editing at this site profoundly affects the properties of GluR2 containing AMPARs, making GluR2 a key determinant of AMPAR function.