Scholarlink

<p>Upon ligand-induced activation, G-protein-coupled receptors (GPCRs) recruit β-arrestins (βarrs) to the plasma membrane, where phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P<sub>2</sub>) stabilizes the GPCR–βarr complex. Although PtdIns(4,5)P<sub>2</sub> is reported to form nanoscale clusters, the spatiotemporal dynamics of how the GPCR–βarr–PtdIns(4,5)P<sub>2</sub> complex assembles and organizes in living cells remain unexplored. Here we demonstrate that multiple PtdIns(4,5)P<sub>2</sub>-binding sites on βarrs cooperatively promote GPCR–βarr assembly in membrane domains. Using molecular dynamics simulations, we identify a noncanonical (NC) PtdIns(4,5)P<sub>2</sub>-binding site, distinct from the known canonical site. Biochemical assays confirm that both sites are essential for βarr binding to PtdIns(4,5)P<sub>2</sub>-containing liposomes, while NanoBiT assays reveal synergistic contributions of both sites for βarr recruitment in living cells. Notably, single-molecule imaging demonstrates that the NC site is required for the rapid accumulation of the GPCR–βarr–PtdIns(4,5)P<sub>2</sub> complex into immobile membrane domains upon ligand stimulation. Collectively, our findings highlight how multivalent βarr–PtdIns(4,5)P<sub>2</sub> interactions drive GPCR–βarr compartmentalization, adding complexity to GPCR signaling dynamics.</p><p></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

Membrane-domain compartmentalization of active GPCRs by β-arrestins through PtdIns(4,5)P2 binding

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年8月6日

查看全文
  • Ritsuki Kuramoto,
  • Tatsuya Ikuta,
  • Carlo Marion C. Carino,
  • Kouki Kawakami,
  • Miisha Kushiro,
  • Chihiro Watanabe,
  • Yasunori Uchida,
  • Mitsuhiro Abe,
  • Yasushi Sako,
  • Tomohiko Taguchi,
  • Masataka Yanagawa,
  • Asuka Inoue

摘要

Upon ligand-induced activation, G-protein-coupled receptors (GPCRs) recruit β-arrestins (βarrs) to the plasma membrane, where phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2) stabilizes the GPCR–βarr complex. Although PtdIns(4,5)P2 is reported to form nanoscale clusters, the spatiotemporal dynamics of how the GPCR–βarr–PtdIns(4,5)P2 complex assembles and organizes in living cells remain unexplored. Here we demonstrate that multiple PtdIns(4,5)P2-binding sites on βarrs cooperatively promote GPCR–βarr assembly in membrane domains. Using molecular dynamics simulations, we identify a noncanonical (NC) PtdIns(4,5)P2-binding site, distinct from the known canonical site. Biochemical assays confirm that both sites are essential for βarr binding to PtdIns(4,5)P2-containing liposomes, while NanoBiT assays reveal synergistic contributions of both sites for βarr recruitment in living cells. Notably, single-molecule imaging demonstrates that the NC site is required for the rapid accumulation of the GPCR–βarr–PtdIns(4,5)P2 complex into immobile membrane domains upon ligand stimulation. Collectively, our findings highlight how multivalent βarr–PtdIns(4,5)P2 interactions drive GPCR–βarr compartmentalization, adding complexity to GPCR signaling dynamics.