title: Multiparameter behavioral profiling reveals distinct thermal response regimes in Caenorhabditis elegans.
abstract: BACKGROUND
  Responding to noxious stimuli by invoking an appropriate escape response is critical for survival of an organism. The sensations of small and large changes in temperature in most organisms have been studied separately in the context of thermotaxis and nociception, respectively. Here we use the nematode C. elegans to address the neurogenetic basis of responses to thermal stimuli over a broad range of intensities.
  
  
  RESULTS
  C. elegans responds to aversive temperature by eliciting a stereotypical behavioral sequence. Upon sensation of the noxious stimulus, it moves backwards, turns and resumes forward movement in a new direction. In order to study the response of C. elegans to a broad range of noxious thermal stimuli, we developed a novel assay that allows simultaneous characterization of multiple aspects of escape behavior elicited by thermal pulses of increasing amplitudes. We exposed the laboratory strain N2, as well as 47 strains with defects in various aspects of nervous system function, to thermal pulses ranging from ΔT = 0.4°C to 9.1°C and recorded the resulting behavioral profiles.
  
  
  CONCLUSIONS
  Through analysis of the multidimensional behavioral profiles, we found that the combinations of molecules shaping avoidance responses to a given thermal pulse are unique. At different intensities of aversive thermal stimuli, these distinct combinations of molecules converge onto qualitatively similar stereotyped behavioral sequences.
authors.affiliation: Lewis-Sigler Institute for Integrative Genomics, Department of Ecology and Evolutionary Biology, Princeton University, Washington Road, Princeton, NJ 08544, USA.
authors.forename: Rajarshi
authors.initials: R
authors.lastname: Ghosh
authors.forename: Aylia
authors.initials: A
authors.lastname: Mohammadi
authors.forename: Leonid
authors.initials: L
authors.lastname: Kruglyak
authors.forename: William S
authors.initials: WS
authors.lastname: Ryu
mesh_terms: D000818:Animals; D001362:Avoidance Learning / Q000502:physiology; D001522:Behavior, Animal / Q000502:physiology*; D017173:Caenorhabditis elegans / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins / Q000378:metabolism; D016000:Cluster Analysis; D004924:Escape Reaction / Q000502:physiology; D005971:Glutamates / Q000378:metabolism; D006358:Hot Temperature; D009068:Movement; D009479:Neuropeptides / Q000378:metabolism; D018377:Neurotransmitter Agents / Q000378:metabolism; D010641:Phenotype; D010812:Physical Stimulation; D015221:Potassium Channels / Q000378:metabolism; D025341:Principal Component Analysis; D009435:Synaptic Transmission / Q000502:physiology; D013697:Thermosensing / Q000502:physiology*
chemical_list: D029742:Caenorhabditis elegans Proteins; D005971:Glutamates; D009479:Neuropeptides; D018377:Neurotransmitter Agents; D015221:Potassium Channels