Abnormal Osmotic Avoidance Behavior in C. elegans Is Associated with Increased Hypertonic Stress Resistance and Improved Proteostasis

PLoS One. 2016 Apr 25;11(4):e0154156. doi: 10.1371/journal.pone.0154156. eCollection 2016.

Abstract

Protein function is controlled by the cellular proteostasis network. Proteostasis is energetically costly and those costs must be balanced with the energy needs of other physiological functions. Hypertonic stress causes widespread protein damage in C. elegans. Suppression and management of protein damage is essential for optimal survival under hypertonic conditions. ASH chemosensory neurons allow C. elegans to detect and avoid strongly hypertonic environments. We demonstrate that mutations in osm-9 and osm-12 that disrupt ASH mediated hypertonic avoidance behavior or genetic ablation of ASH neurons are associated with enhanced survival during hypertonic stress. Improved survival is not due to altered systemic volume homeostasis or organic osmolyte accumulation. Instead, we find that osm-9(ok1677) mutant and osm-9(RNAi) worms exhibit reductions in hypertonicity induced protein damage in non-neuronal cells suggesting that enhanced proteostasis capacity may account for improved hypertonic stress resistance in worms with defects in osmotic avoidance behavior. RNA-seq analysis revealed that genes that play roles in managing protein damage are upregulated in osm-9(ok1677) worms. Our findings are consistent with a growing body of work demonstrating that intercellular communication between neuronal and non-neuronal cells plays a critical role in integrating cellular stress resistance with other organismal physiological demands and associated energy costs.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adaptation, Physiological / genetics
  • Animals
  • Avoidance Learning / drug effects*
  • Caenorhabditis elegans / drug effects*
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans / metabolism
  • Caenorhabditis elegans Proteins / genetics*
  • Caenorhabditis elegans Proteins / metabolism
  • Cell Communication
  • Gene Expression Profiling
  • Gene Expression Regulation
  • Longevity / drug effects*
  • Longevity / genetics
  • Mutation
  • Nerve Tissue Proteins / genetics*
  • Nerve Tissue Proteins / metabolism
  • Neurons / cytology
  • Neurons / drug effects
  • Neurons / metabolism
  • Osmoregulation / genetics*
  • Osmotic Pressure
  • Protein Isoforms
  • Protein Stability / drug effects
  • Sequence Analysis, RNA
  • Signal Transduction
  • Sodium Chloride / pharmacology*
  • Stress, Physiological
  • Survival Rate
  • TRPV Cation Channels / genetics*
  • TRPV Cation Channels / metabolism

Substances

  • Caenorhabditis elegans Proteins
  • Nerve Tissue Proteins
  • OSM-9 protein, C elegans
  • Protein Isoforms
  • TRPV Cation Channels
  • Sodium Chloride