Glutamate receptor dynamics, structure and function at synapses

Information transfer and storage in the nervous system occurs at synapses. Ionotropic glutamate receptors mediate the majority of excitatory signal transmission; AMPA-type glutamate-receptors (AMPARs) also centrally contribute to synaptic plasticity, a process that underlies learning. Malfunction of these receptors underlies various neurological disorders such as epilepsy and neurodegeneration. My lab is utilizing various approaches, including structural biology, cell biology, electrophysiology and super-resolution imaging to understand mechanisms underlying AMPA-R regulation and signalling at synapses.

We will be capitalising on our structural and functional data to explore regulation of synaptic AMPA-R positioning via its large N-terminal domain (NTD) (Herguedas al., 2016; Watson et al., 2017) to ultimately understand how AMPAR are slotted into synapses during synaptic plasticity/learning. This will include:

A combination of super-resolution microscopy (3D-STORM) and slice electrophysiology/optogenetics to study how the NTD, via interactions with synaptic proteins (Garcia-Nafria et al., 2016), including AMPA-R auxiliary subunits (Cais et al., 2014), impacts AMPAR recruitment to and clustering at synapses during plasticity.
Using cryo-EM (electron-cryo microscopy), we will sample the AMPAR conformational spectrum (Herguedas et al., 2016), how this is influenced by various AMPAR auxiliary proteins during the gating cycle (Greger et al.,2017). This project also seeks to study AMPAR conformations in situ, using tomographic approaches in HEK293 cells.