Molecular cause and functional impact of altered synaptic lipid signaling due to a prg-1 gene SNP

EMBO Mol Med. 2016 Jan 1;8(1):25-38. doi: 10.15252/emmm.201505677.

Abstract

Loss of plasticity-related gene 1 (PRG-1), which regulates synaptic phospholipid signaling, leads to hyperexcitability via increased glutamate release altering excitation/inhibition (E/I) balance in cortical networks. A recently reported SNP in prg-1 (R345T/mutPRG-1) affects ~5 million European and US citizens in a monoallelic variant. Our studies show that this mutation leads to a loss-of-PRG-1 function at the synapse due to its inability to control lysophosphatidic acid (LPA) levels via a cellular uptake mechanism which appears to depend on proper glycosylation altered by this SNP. PRG-1(+/-) mice, which are animal correlates of human PRG-1(+/mut) carriers, showed an altered cortical network function and stress-related behavioral changes indicating altered resilience against psychiatric disorders. These could be reversed by modulation of phospholipid signaling via pharmacological inhibition of the LPA-synthesizing molecule autotaxin. In line, EEG recordings in a human population-based cohort revealed an E/I balance shift in monoallelic mutPRG-1 carriers and an impaired sensory gating, which is regarded as an endophenotype of stress-related mental disorders. Intervention into bioactive lipid signaling is thus a promising strategy to interfere with glutamate-dependent symptoms in psychiatric diseases.

Keywords: PRG‐1; bioactive phospholipids; cortical network; psychiatric disorders; synapse.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Electroencephalography
  • Evoked Potentials
  • Glycosylation
  • HEK293 Cells
  • Humans
  • Lysophospholipids / metabolism*
  • Mental Disorders / genetics
  • Mental Disorders / pathology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Patch-Clamp Techniques
  • Phosphopeptides / analysis
  • Phosphoric Diester Hydrolases / chemistry
  • Phosphoric Diester Hydrolases / metabolism
  • Phosphorylation
  • Polymorphism, Single Nucleotide*
  • Proteoglycans / genetics*
  • Proteoglycans / metabolism
  • Signal Transduction / genetics*
  • Somatosensory Cortex / metabolism
  • Somatosensory Cortex / pathology
  • Synapses / metabolism*
  • Vesicular Transport Proteins / genetics*
  • Vesicular Transport Proteins / metabolism

Substances

  • Lysophospholipids
  • Phosphopeptides
  • Proteoglycans
  • Vesicular Transport Proteins
  • serglycin
  • Phosphoric Diester Hydrolases
  • alkylglycerophosphoethanolamine phosphodiesterase
  • lysophosphatidic acid