Expression of nicotinic acetylcholine receptor subunits from parasitic nematodes in Caenorhabditis elegans

Mol Biochem Parasitol. 2015 Nov;204(1):44-50. doi: 10.1016/j.molbiopara.2015.12.006. Epub 2015 Dec 30.


The levamisole-sensitive nicotinic acetylcholine receptor present at nematode neuromuscular junctions is composed of multiple different subunits, with the exact composition varying between species. We tested the ability of two well-conserved nicotinic receptor subunits, UNC-38 and UNC-29, from Haemonchus contortus and Ascaris suum to rescue the levamisole-resistance and locomotion defects of Caenorhabditis elegans strains with null deletion mutations in the unc-38 and unc-29 genes. The parasite cDNAs were cloned downstream of the relevant C. elegans promoters and introduced into the mutant strains via biolistic transformation. The UNC-38 subunit of H. contortus was able to completely rescue both the locomotion defects and levamisole resistance of the null deletion mutant VC2937 (ok2896), but no C. elegans expressing the A. suum UNC-38 could be detected. The H. contortus UNC-29.1 subunit partially rescued the levamisole resistance of a C. elegans null mutation in unc-29 VC1944 (ok2450), but did cause increased motility in a thrashing assay. In contrast, only a single line of worms containing the A. suum UNC-29 subunit showed a partial rescue of levamisole resistance, with no effect on thrashing.

Keywords: Ascaris suum; Caenorhabditis elegans; Haemonchus contortus; Levamisole; Nicotinic acetylcholine receptor.

Publication types

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

MeSH terms

  • Animals
  • Antinematodal Agents / pharmacology*
  • Ascaris suum / drug effects
  • Ascaris suum / genetics*
  • Biolistics
  • Caenorhabditis elegans / genetics*
  • Caenorhabditis elegans Proteins / genetics*
  • Carrier Proteins / genetics*
  • Cloning, Molecular
  • DNA, Complementary / genetics
  • DNA, Helminth / genetics
  • Drug Resistance / genetics*
  • Haemonchus / drug effects
  • Haemonchus / genetics*
  • Levamisole / pharmacology*
  • Locomotion / genetics
  • Protein Subunits / genetics
  • Receptors, Nicotinic / genetics*
  • Sequence Deletion


  • Antinematodal Agents
  • Caenorhabditis elegans Proteins
  • Carrier Proteins
  • DNA, Complementary
  • DNA, Helminth
  • Protein Subunits
  • Receptors, Nicotinic
  • UNC-29 protein, C elegans
  • Unc-38 protein, C elegans
  • Levamisole