C. elegans locomotory rate is modulated by the environment through a dopaminergic pathway and by experience through a serotonergic pathway

Neuron. 2000 Jun;26(3):619-31. doi: 10.1016/s0896-6273(00)81199-x.


Caenorhabditis elegans modulates its locomotory rate in response to its food, bacteria, in two ways. First, well-fed wild-type animals move more slowly in the presence of bacteria than in the absence of bacteria. This basal slowing response is mediated by a dopamine-containing neural circuit that senses a mechanical attribute of bacteria and may be an adaptive mechanism that increases the amount of time animals spend in the presence of food. Second, food-deprived wild-type animals, when transferred to bacteria, display a dramatically enhanced slowing response that ensures that the animals do not leave their newly encountered source of food. This experience-dependent response is mediated by serotonergic neurotransmission and is potentiated by fluoxetine (Prozac). The basal and enhanced slowing responses are distinct and separable neuromodulatory components of a genetically tractable paradigm of behavioral plasticity.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Caenorhabditis elegans / physiology*
  • Caenorhabditis elegans Proteins*
  • Catalase / genetics
  • Dopamine / pharmacology
  • Dopamine / physiology*
  • Environment*
  • Escherichia coli / physiology
  • Fluoxetine / pharmacology
  • Food Deprivation / physiology
  • Fungal Proteins / genetics
  • Helminth Proteins / genetics
  • Mechanoreceptors / physiology
  • Mixed Function Oxygenases*
  • Motor Activity / drug effects
  • Motor Activity / physiology*
  • Mutation / physiology
  • Neurons / physiology
  • Selective Serotonin Reuptake Inhibitors / pharmacology
  • Serotonin / physiology*
  • Time Factors
  • Trans-Activators / genetics


  • Caenorhabditis elegans Proteins
  • Fungal Proteins
  • Helminth Proteins
  • Serotonin Uptake Inhibitors
  • Trans-Activators
  • cat-2 protein, C elegans
  • Fluoxetine
  • Serotonin
  • Mixed Function Oxygenases
  • Catalase
  • Dopamine