Antagonism between neuropeptides and monoamines in a distributed circuit for pathogen avoidance

Cell Rep. 2024 Apr 23;43(4):114042. doi: 10.1016/j.celrep.2024.114042. Epub 2024 Apr 3.

Abstract

Pathogenic infection elicits behaviors that promote recovery and survival of the host. After exposure to the pathogenic bacterium Pseudomonas aeruginosa PA14, the nematode Caenorhabditis elegans modifies its sensory preferences to avoid the pathogen. Here, we identify antagonistic neuromodulators that shape this acquired avoidance behavior. Using an unbiased cell-directed neuropeptide screen, we show that AVK neurons upregulate and release RF/RYamide FLP-1 neuropeptides during infection to drive pathogen avoidance. Manipulations that increase or decrease AVK activity accelerate or delay pathogen avoidance, respectively, implicating AVK in the dynamics of avoidance behavior. FLP-1 neuropeptides drive pathogen avoidance through the G protein-coupled receptor DMSR-7, as well as other receptors. DMSR-7 in turn acts in multiple neurons, including tyraminergic/octopaminergic neurons that receive convergent avoidance signals from the cytokine DAF-7/transforming growth factor β. Neuromodulators shape pathogen avoidance through multiple mechanisms and targets, in agreement with the distributed neuromodulatory connectome of C. elegans.

Keywords: CP: Neuroscience; Caenorhabditis elegans; Pathogen avoidance; bacterial pathogens; behavior; neural circuits; neuromodulatory circuits; neuropeptide signaling; pathogen response; pseudomonas aeruginosa PA14; sickness behavior.

Publication types

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

MeSH terms

  • Animals
  • Avoidance Learning / physiology
  • Biogenic Monoamines / metabolism
  • Caenorhabditis elegans Proteins* / metabolism
  • Caenorhabditis elegans* / metabolism
  • Caenorhabditis elegans* / microbiology
  • Neurons / metabolism
  • Neuropeptides* / metabolism
  • Pseudomonas aeruginosa* / metabolism
  • Receptors, G-Protein-Coupled / metabolism
  • Signal Transduction

Substances

  • Neuropeptides
  • Caenorhabditis elegans Proteins
  • Biogenic Monoamines
  • Receptors, G-Protein-Coupled