Disruption of auto-inhibition underlies conformational signaling of ASIC1a to induce neuronal necroptosis

Nat Commun. 2020 Jan 24;11(1):475. doi: 10.1038/s41467-019-13873-0.

Abstract

We reported previously that acid-sensing ion channel 1a (ASIC1a) mediates acidic neuronal necroptosis via recruiting receptor-interacting protein kinase 1 (RIPK1) to its C terminus (CT), independent of its ion-conducting function. Here we show that the N-terminus (NT) of ASIC1a interacts with its CT to form an auto-inhibition that prevents RIPK1 recruitment/activation under resting conditions. The interaction involves glutamate residues at distal NT and is disrupted by acidosis. Expression of mutant ASIC1a bearing truncation or glutamate-to-alanine substitutions at distal NT causes constitutive cell death. The NT-CT interaction is further disrupted by N-ethylmaleimide-sensitive fusion ATPase (NSF), which associates with ASIC1a-NT under acidosis, facilitating RIPK1 interaction with ASIC1a-CT. Importantly, a membrane-penetrating synthetic peptide representing the distal 20 ASIC1a NT residues, NT1-20, reduced neuronal damage in both in vitro model of acidotoxicity and in vivo mouse model of ischemic stroke, demonstrating the therapeutic potential of targeting the auto-inhibition of ASIC1a for neuroprotection against acidotoxicity.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acid Sensing Ion Channels / chemistry*
  • Acid Sensing Ion Channels / genetics
  • Acid Sensing Ion Channels / physiology*
  • Acidosis / pathology
  • Acidosis / physiopathology
  • Amino Acid Substitution
  • Animals
  • Female
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Models, Molecular
  • Models, Neurological
  • N-Ethylmaleimide-Sensitive Proteins / pharmacology
  • N-Ethylmaleimide-Sensitive Proteins / physiology
  • Necroptosis / physiology*
  • Neurons / cytology
  • Neurons / physiology*
  • Neuroprotection / drug effects
  • Neuroprotection / physiology
  • Peptide Fragments / chemistry
  • Peptide Fragments / genetics
  • Peptide Fragments / physiology
  • Protein Conformation
  • Protein Interaction Domains and Motifs
  • Receptor-Interacting Protein Serine-Threonine Kinases / antagonists & inhibitors
  • Receptor-Interacting Protein Serine-Threonine Kinases / physiology
  • Signal Transduction
  • Stroke / pathology
  • Stroke / physiopathology

Substances

  • ASIC1 protein, mouse
  • Acid Sensing Ion Channels
  • Peptide Fragments
  • Receptor-Interacting Protein Serine-Threonine Kinases
  • Ripk1 protein, mouse
  • N-Ethylmaleimide-Sensitive Proteins