Mechanisms of Channel Block in Calcium-Permeable AMPA Receptors.
Twomey, E.C., Yelshanskaya, M.V., Vassilevski, A.A., Sobolevsky, A.I.(2018) Neuron 99: 956-968.e4
- PubMed: 30122377 
- DOI: https://doi.org/10.1016/j.neuron.2018.07.027
- Primary Citation of Related Structures:  
6DLZ, 6DM0, 6DM1, 6O9G - PubMed Abstract: 
AMPA receptors mediate fast excitatory neurotransmission and are critical for CNS development and function. Calcium-permeable subsets of AMPA receptors are strongly implicated in acute and chronic neurological disorders. However, despite the clinical importance, the therapeutic landscape for specifically targeting them, and not the calcium-impermeable AMPA receptors, remains largely undeveloped. To address this problem, we used cryo-electron microscopy and electrophysiology to investigate the mechanisms by which small-molecule blockers selectively inhibit ion channel conductance in calcium-permeable AMPA receptors. We determined the structures of calcium-permeable GluA2 AMPA receptor complexes with the auxiliary subunit stargazin bound to channel blockers, including the orb weaver spider toxin AgTx-636, the spider toxin analog NASPM, and the adamantane derivative IEM-1460. Our structures provide insights into the architecture of the blocker binding site and the mechanism of trapping, which are critical for development of small molecules that specifically target calcium-permeable AMPA receptors.
Organizational Affiliation: 
Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA; Integrated Program in Cellular, Molecular and Biomedical Studies, Columbia University, New York, NY 10032, USA.