Decoding the intensity of sensory input by two glutamate receptors in one C. elegans interneuron

Nat Commun. 2018 Oct 17;9(1):4311. doi: 10.1038/s41467-018-06819-5.


How neurons are capable of decoding stimulus intensity and translate this information into complex behavioral outputs is poorly defined. Here, we demonstrate that the C. elegans interneuron AIB regulates two types of behaviors: reversal initiation and feeding suppression in response to different concentrations of quinine. Low concentrations of quinine are decoded in AIB by a low-threshold, fast-inactivation glutamate receptor GLR-1 and translated into reversal initiation. In contrast, high concentrations of quinine are decoded by a high-threshold, slow-inactivation glutamate receptor GLR-5 in AIB. After activation, GLR-5 evokes sustained Ca2+ release from the inositol 1,4,5-trisphosphate (IP3)-sensitive Ca2+ stores and triggers neuropeptide secretion, which in turn activates the downstream neuron RIM and inhibits feeding. Our results reveal that distinct signal patterns in a single interneuron AIB can encode differential behavioral outputs depending on the stimulus intensity, thus highlighting the importance of functional mapping of information propagation at the single-neuron level during connectome construction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Caenorhabditis elegans / physiology*
  • Caenorhabditis elegans Proteins / metabolism*
  • Calcium Signaling
  • Carrier Proteins / metabolism
  • Feeding Behavior / physiology*
  • Interneurons / physiology*
  • Quinine
  • Receptors, AMPA / metabolism*
  • Sensory Receptor Cells / physiology
  • Sensory Thresholds


  • Caenorhabditis elegans Proteins
  • Carrier Proteins
  • GLR-5 protein, C elegans
  • Receptors, AMPA
  • glr-1 protein, C elegans
  • unc-10 protein, C elegans
  • Quinine