Scholarlink

<p>AMPA-type glutamate receptors, fundamental ion channels for fast excitatory neurotransmission and synaptic plasticity, contain a GluA tetrameric core surrounded by auxiliary proteins such as transmembrane AMPA receptor regulatory proteins (TARPs) or Cornichons. Their exact composition and stoichiometry govern functional properties, including kinetics, calcium permeability and trafficking. The GluA1–GluA3 subunits predominate in the adult forebrain and are well characterized. However, we lack structural information on full-length GluA4-containing AMPARs, a subtype that has specific roles in brain development and specific cell types in mammals. Here we present the cryo-electron microscopy structures of rat GluA4:TARP-γ2 trapped in active, resting and desensitized states, covering a full gating cycle. Additionally, we describe the structure of GluA4 alone, which displays a classical Y-shaped conformation. In resting conditions, GluA4:TARP-γ2 adopts two conformations, one resembling the desensitized states of other GluA subunits. Moreover, we identify a regulatory site for TARP-γ2 in the ligand-binding domain that modulates gating kinetics. Our findings uncover distinct features of GluA4, highlighting how subunit composition and auxiliary proteins shape receptor structure and dynamics, expanding glutamatergic signaling diversity.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

GluA4 AMPA receptor gating mechanisms and modulation by auxiliary proteins

  • 期刊论文

  • 发表日期：

    2025年9月15日

查看全文
  • Carlos Vega-Gutiérrez,
  • Javier Picañol-Párraga,
  • Irene Sánchez-Valls,
  • Victoria del Pilar Ribón-Fuster,
  • David Soto,
  • Beatriz Herguedas

摘要

AMPA-type glutamate receptors, fundamental ion channels for fast excitatory neurotransmission and synaptic plasticity, contain a GluA tetrameric core surrounded by auxiliary proteins such as transmembrane AMPA receptor regulatory proteins (TARPs) or Cornichons. Their exact composition and stoichiometry govern functional properties, including kinetics, calcium permeability and trafficking. The GluA1–GluA3 subunits predominate in the adult forebrain and are well characterized. However, we lack structural information on full-length GluA4-containing AMPARs, a subtype that has specific roles in brain development and specific cell types in mammals. Here we present the cryo-electron microscopy structures of rat GluA4:TARP-γ2 trapped in active, resting and desensitized states, covering a full gating cycle. Additionally, we describe the structure of GluA4 alone, which displays a classical Y-shaped conformation. In resting conditions, GluA4:TARP-γ2 adopts two conformations, one resembling the desensitized states of other GluA subunits. Moreover, we identify a regulatory site for TARP-γ2 in the ligand-binding domain that modulates gating kinetics. Our findings uncover distinct features of GluA4, highlighting how subunit composition and auxiliary proteins shape receptor structure and dynamics, expanding glutamatergic signaling diversity.