Jedi-1 deficiency increases sensory neuron excitability through a non-cell autonomous mechanism

Sci Rep. 2020 Jan 28;10(1):1300. doi: 10.1038/s41598-020-57971-2.

Abstract

The dorsal root ganglia (DRG) house the primary afferent neurons responsible for somatosensation, including pain. We previously identified Jedi-1 (PEAR1/MEGF12) as a phagocytic receptor expressed by satellite glia in the DRG involved in clearing apoptotic neurons during development. Here, we further investigated the function of this receptor in vivo using Jedi-1 null mice. In addition to satellite glia, we found Jedi-1 expression in perineurial glia and endothelial cells, but not in sensory neurons. We did not detect any morphological or functional changes in the glial cells or vasculature of Jedi-1 knockout mice. Surprisingly, we did observe changes in DRG neuron activity. In neurons from Jedi-1 knockout (KO) mice, there was an increase in the fraction of capsaicin-sensitive cells relative to wild type (WT) controls. Patch-clamp electrophysiology revealed an increase in excitability, with a shift from phasic to tonic action potential firing patterns in KO neurons. We also found alterations in the properties of voltage-gated sodium channel currents in Jedi-1 null neurons. These results provide new insight into the expression pattern of Jedi-1 in the peripheral nervous system and indicate that loss of Jedi-1 alters DRG neuron activity indirectly through an intercellular interaction between non-neuronal cells and sensory neurons.

MeSH terms

  • Action Potentials*
  • Animals
  • Biomarkers
  • Cell Line
  • Ganglia, Spinal / cytology
  • Ganglia, Spinal / metabolism
  • Humans
  • Immunohistochemistry
  • Mice
  • Mice, Knockout
  • Mice, Transgenic
  • Neuroglia / metabolism
  • Neuroglia / ultrastructure
  • Patch-Clamp Techniques
  • Receptors, Cell Surface / deficiency*
  • Sensory Receptor Cells / metabolism*
  • Sensory Receptor Cells / ultrastructure

Substances

  • Biomarkers
  • PEAR1 protein, mouse
  • Receptors, Cell Surface