Sensing of cadmium and copper ions by externally exposed ADL, ASE, and ASH neurons elicits avoidance response in Caenorhabditis elegans

Neuroreport. 1999 Mar 17;10(4):753-7. doi: 10.1097/00001756-199903170-00017.


We developed a quantitative assay for Caenorhabditis elegans avoidance behavior. This was then used to demonstrate that the worm moved away from toxic concentrations of Cd2+ and Cu2+, but not Ni2+, all ions that prevented development from larval to adult stages. Mutants that have structural defects in ciliated neurons (che-2 and osm-3) as well as worms with three laser-operated neurons (ADL, ASE, and ASH), showed no avoidance behavior from Cd2+ and Cu2+. These results suggest that the avoidance from Cd2+ and Cu2+ are mediated through multiple neural pathways including ADL, ASE, and ASH neurons. We hypothesize that the three sensing neurons provide increased accuracy of the sensory response and a survival advantage in the natural environment of the worm.

Publication types

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

MeSH terms

  • Animals
  • Avoidance Learning / physiology
  • Cadmium / pharmacology*
  • Caenorhabditis elegans / physiology*
  • Chemoreceptor Cells / physiology*
  • Cilia / physiology
  • Copper / pharmacology*
  • Larva
  • Laser Therapy
  • Mutation
  • Neural Pathways / cytology
  • Neural Pathways / physiology
  • Neurons, Afferent / drug effects*
  • Neurons, Afferent / physiology
  • Nickel / pharmacology


  • Cadmium
  • Copper
  • Nickel