National Institutes of Health/National Institute of Neurological Disorders and Stroke (NIH/NINDS)
NS093838
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
GM008224
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
GM008281
米国
National Institutes of Health/National Institute of Neurological Disorders and Stroke (NIH/NINDS)
NS083660
米国
National Institutes of Health/National Cancer Institute (NIH/NCI)
CA206573
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
GM029169
米国
Howard Hughes Medical Institute (HHMI)
米国
引用
ジャーナル: Neuron / 年: 2017 タイトル: Structural Bases of Desensitization in AMPA Receptor-Auxiliary Subunit Complexes. 著者: Edward C Twomey / Maria V Yelshanskaya / Robert A Grassucci / Joachim Frank / Alexander I Sobolevsky / 要旨: Fast excitatory neurotransmission is mediated by AMPA-subtype ionotropic glutamate receptors (AMPARs). AMPARs, localized at post-synaptic densities, are regulated by transmembrane auxiliary subunits ...Fast excitatory neurotransmission is mediated by AMPA-subtype ionotropic glutamate receptors (AMPARs). AMPARs, localized at post-synaptic densities, are regulated by transmembrane auxiliary subunits that modulate AMPAR assembly, trafficking, gating, and pharmacology. Aberrancies in AMPAR-mediated signaling are associated with numerous neurological disorders. Here, we report cryo-EM structures of an AMPAR in complex with the auxiliary subunit GSG1L in the closed and desensitized states. GSG1L favors the AMPAR desensitized state, where channel closure is facilitated by profound structural rearrangements in the AMPAR extracellular domain, with ligand-binding domain dimers losing their local 2-fold rotational symmetry. Our structural and functional experiments suggest that AMPAR auxiliary subunits share a modular architecture and use a common transmembrane scaffold for distinct extracellular modules to differentially regulate AMPAR gating. By comparing the AMPAR-GSG1L complex structures, we map conformational changes accompanying AMPAR recovery from desensitization and reveal structural bases for regulation of synaptic transmission by auxiliary subunits.