title: GPA-14, a Gα(i) subunit mediates dopaminergic behavioral plasticity in C. elegans.
abstract: BACKGROUND
  Precise levels of specific neurotransmitters are required for appropriate neuronal functioning. The neurotransmitter dopamine is implicated in modulating behaviors, such as cognition, reward and memory. In the nematode Caenorhabditis elegans, the release of dopamine during behavioral plasticity is in part modulated through an acid-sensing ion channel expressed in its eight dopaminergic neurons. A D2-like C. elegans dopamine receptor DOP-2 co-expresses along with a Gα(i) subunit (GPA-14) in the anterior deirid (ADE) pair of dopaminergic neurons.
  
  
  RESULTS
  In follow-up experiments to our recently reported in vitro physical interaction between DOP-2 and GPA-14, we have behaviorally characterized worms carrying deletion mutations in gpa-14 and/or dop-2. We found both mutants to display behavioral abnormalities in habituation as well as associative learning, and exogenous supply of dopamine was able to revert the observed behavioral deficits. The behavioral phenotypes of dop-2 and gpa-14 loss-of-function mutants were found to be remarkably similar, and we did not observe any cumulative defects in their double mutants.
  
  
  CONCLUSIONS
  Our results provide genetic and phenotypic support to our earlier in vitro results where we had shown that the DOP-2 dopamine receptor and the GPA-14 Gα(i) subunit physically interact with each other. Results from behavioral experiments presented here together with our previous in-vitro work suggests that the DOP-2 functions as a dopamine auto-receptor to modulate two types of learning, anterior touch habituation and chemosensory associative conditioning, through a G-protein complex that comprises GPA-14 as its Gα subunit.
authors.affiliation: Department of Biological Sciences, Delaware State University, Dover, DE 19901, USA.
authors.forename: Mahlet
authors.initials: M
authors.lastname: Mersha
authors.forename: Rosaria
authors.initials: R
authors.lastname: Formisano
authors.forename: Rochelle
authors.initials: R
authors.lastname: McDonald
authors.forename: Pratima
authors.initials: P
authors.lastname: Pandey
authors.forename: Nektarios
authors.initials: N
authors.lastname: Tavernarakis
authors.forename: Singh
authors.initials: S
authors.lastname: Harbinder
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D017173:Caenorhabditis elegans / Q000502:physiology*; D002633:Chemotaxis; D062965:Cyclic GMP-Dependent Protein Kinase Type I / Q000235:genetics* / Q000502:physiology*; D004298:Dopamine / Q000494:pharmacology; D059290:Dopaminergic Neurons / Q000502:physiology*; D017353:Gene Deletion; D009154:Mutation / Q000235:genetics; D009473:Neuronal Plasticity / Q000235:genetics* / Q000502:physiology*; D010641:Phenotype; D010812:Physical Stimulation; D017448:Receptors, Dopamine D2 / Q000235:genetics / Q000502:physiology
chemical_list: D017448:Receptors, Dopamine D2; D062965:Cyclic GMP-Dependent Protein Kinase Type I; D004298:Dopamine