Heat Avoidance Is Regulated by Transient Receptor Potential (TRP) Channels and a Neuropeptide Signaling Pathway in Caenorhabditis elegans

The ability to avoid noxious extremes of hot and cold is critical for survival and depends on thermal nociception. The TRPV subset of transient receptor potential (TRP) channels is heat activated and proposed to be responsible for heat detection in vertebrates and fruit flies. To gain insight into the genetic and neural basis of thermal nociception, we developed assays that quantify noxious heat avoidance in the nematode Caenorhabditis elegans and used them to investigate the genetic basis of this behavior. First, we screened mutants for 18 TRP channel genes (including all TRPV orthologs) and found only minor defects in heat avoidance in single and selected double and triple mutants, indicating that other genes are involved. Next, we compared two wild isolates of C. elegans that diverge in their threshold for heat avoidance and linked this phenotypic variation to a polymorphism in the neuropeptide receptor gene npr-1. Further analysis revealed that loss of either the NPR-1 receptor or its ligand, FLP-21, increases the threshold for heat avoidance. Cell-specific rescue of npr-1 implicates the interneuron RMG in the circuit regulating heat avoidance. This neuropeptide signaling pathway operates independently of the TRPV genes, osm-9 and ocr-2, since mutants lacking npr-1 and both TRPV channels had more severe defects in heat avoidance than mutants lacking only npr-1 or both osm-9 and ocr-2. Our results show that TRPV channels and the FLP-21/NPR-1 neuropeptide signaling pathway determine the threshold for heat avoidance in C. elegans.

[1]  Cori Bargmann,et al.  Combinatorial Expression of TRPV Channel Proteins Defines Their Sensory Functions and Subcellular Localization in C. elegans Neurons , 2002, Neuron.

[2]  G. Bedoya,et al.  A Gain-of-Function Mutation in TRPA1 Causes Familial Episodic Pain Syndrome , 2010, Neuron.

[3]  M. Chalfie,et al.  The mec-4 gene is a member of a family of Caenorhabditis elegans genes that can mutate to induce neuronal degeneration , 1991, Nature.

[4]  S. Waxman,et al.  Mutations in sodium-channel gene SCN9A cause a spectrum of human genetic pain disorders. , 2007, The Journal of clinical investigation.

[5]  K. Shen,et al.  Wnt Signaling Positions Neuromuscular Connectivity by Inhibiting Synapse Formation in C. elegans , 2007, Cell.

[6]  Patrick W. Hullett,et al.  BMC Genomics BioMed Central Methodology article Rapid single nucleotide polymorphism mapping in C. elegans , 2005 .

[7]  E. Hafez.  Behavioral thermoregulation in mammals and birds , 1964 .

[8]  R. B. Hey.  Behavioral thermoregulation in lizards: importance of associated costs. , 1974, Science.

[9]  W. Gish,et al.  Rapid gene mapping in Caenorhabditis elegans using a high density polymorphism map , 2001, Nature Genetics.

[10]  Evan Z. Macosko,et al.  Quantitative Mapping of a Digenic Behavioral Trait Implicates Globin Variation in C. elegans Sensory Behaviors , 2009, Neuron.

[11]  Cori Bargmann,et al.  Natural Variation in a Neuropeptide Y Receptor Homolog Modifies Social Behavior and Food Response in C. elegans , 1998, Cell.

[12]  W. Maixner,et al.  Genetic basis for individual variations in pain perception and the development of a chronic pain condition. , 2005, Human molecular genetics.

[13]  F. Seebacher.  Behavioural Postures and the Rate of Body Temperature Change in Wild Freshwater Crocodiles, Crocodylus johnstoni , 1999, Physiological and Biochemical Zoology.

[14]  I. Mori,et al.  Neural regulation of thermotaxis in Caenorhabditis elegans , 1995, Nature.

[15]  Oliver Hobert,et al.  A Conserved Postsynaptic Transmembrane Protein Affecting Neuromuscular Signaling in Caenorhabditis elegans , 2004, The Journal of Neuroscience.

[16]  Cori Bargmann,et al.  Social feeding in Caenorhabditis elegans is induced by neurons that detect aversive stimuli , 2002, Nature.

[17]  Jody Hey,et al.  Population genetics of Caenorhabditis elegans: the paradox of low polymorphism in a widespread species. , 2003, Genetics.

[18]  Greg J. Stephens,et al.  Dimensionality and Dynamics in the Behavior of C. elegans , 2007, PLoS Comput. Biol..

[19]  R. Gentry.  Thermoregulatory behavior of eared seals. , 1973, Behaviour.

[20]  Oliver Hobert,et al.  Hypoxia activates a latent circuit for processing gustatory information in C. elegans , 2010, Nature Neuroscience.

[21]  Aravinthan D. T. Samuel,et al.  Running hot and cold: behavioral strategies, neural circuits, and the molecular machinery for thermotaxis in C. elegans and Drosophila. , 2010, Genes & development.

[22]  P. Phillips,et al.  Beyond induced mutants: using worms to study natural variation in genetic pathways. , 2008, Trends in genetics : TIG.

[23]  J. Bessereau,et al.  [C. elegans: of neurons and genes]. , 2003, Medecine sciences : M/S.

[24]  Minna Männikkö,et al.  Pain perception is altered by a nucleotide polymorphism in SCN9A , 2010, Proceedings of the National Academy of Sciences.

[25]  A. Cutter.  Nucleotide Polymorphism and Linkage Disequilibrium in Wild Populations of the Partial Selfer Caenorhabditis elegans , 2006, Genetics.

[26]  W. Schafer,et al.  Specific roles for DEG/ENaC and TRP channels in touch and thermosensation in C. elegans nociceptors , 2010, Nature Neuroscience.

[27]  Benjamin R. Myers,et al.  Evolution of Thermal Response Properties in a Cold-Activated TRP Channel , 2009, PloS one.

[28]  L. Kruglyak,et al.  Recombinational Landscape and Population Genomics of Caenorhabditis elegans , 2009, PLoS genetics.

[29]  Aravinthan D. T. Samuel,et al.  The role of the AFD neuron in C. elegans thermotaxis analyzed using femtosecond laser ablation , 2006, BMC Neuroscience.

[30]  Mario de Bono,et al.  Antagonistic pathways in neurons exposed to body fluid regulate social feeding in Caenorhabditis elegans , 2002, Nature.

[31]  R. B. Azevedo,et al.  npr-1 Regulates Foraging and Dispersal Strategies in Caenorhabditis elegans , 2008, Current Biology.

[32]  L. Kruglyak,et al.  Widespread Genetic Incompatibility in C. Elegans Maintained by Balancing Selection , 2008, Science.

[33]  J. Bettinger,et al.  Natural Variation in the npr-1 Gene Modifies Ethanol Responses of Wild Strains of C. elegans , 2004, Neuron.

[34]  Chuong B. Do,et al.  ProbCons: Probabilistic consistency-based multiple sequence alignment. , 2005, Genome research.

[35]  Aravinthan D. T. Samuel,et al.  Temperature and food mediate long-term thermotactic behavioral plasticity by association-independent mechanisms in C. elegans , 2007, Journal of Experimental Biology.

[36]  N. Wittenburg,et al.  Thermal avoidance in Caenorhabditis elegans: an approach to the study of nociception. , 1999, Proceedings of the National Academy of Sciences of the United States of America.

[37]  Atsushi Kuhara,et al.  Worm thermotaxis: a model system for analyzing thermosensation and neural plasticity , 2007, Current Opinion in Neurobiology.

[38]  Raymond B Huey,et al.  Thermal preference of Caenorhabditis elegans: a null model and empirical tests , 2007, Journal of Experimental Biology.

[39]  Miriam B Goodman,et al.  Transducing touch in Caenorhabditis elegans. , 2003, Annual review of physiology.

[40]  R. L. Russell,et al.  Normal and mutant thermotaxis in the nematode Caenorhabditis elegans. , 1975, Proceedings of the National Academy of Sciences of the United States of America.

[41]  Navin Pokala,et al.  Neurons Detect Increases and Decreases in Oxygen Levels Using Distinct Guanylate Cyclases , 2009, Neuron.

[42]  O. Gascuel,et al.  Estimating maximum likelihood phylogenies with PhyML. , 2009, Methods in molecular biology.

[43]  Cori Bargmann,et al.  TRP channels in C. elegans. , 2006, Annual review of physiology.

[44]  Broome,et al.  Literature cited , 1924, A Guide to the Carnivores of Central America.

[45]  N. Munakata.  [Genetics of Caenorhabditis elegans]. , 1989, Tanpakushitsu kakusan koso. Protein, nucleic acid, enzyme.

[46]  M. Félix,et al.  The natural history of Caenorhabditis elegans , 2010, Current Biology.

[47]  Daniel Ramot,et al.  Thermotaxis is a Robust Mechanism for Thermoregulation in Caenorhabditis elegans Nematodes , 2008, The Journal of Neuroscience.

[48]  O. Gascuel,et al.  An improved general amino acid replacement matrix. , 2008, Molecular biology and evolution.

[49]  Mario de Bono,et al.  Inhibition of Caenorhabditis elegans social feeding by FMRFamide-related peptide activation of NPR-1 , 2003, Nature Neuroscience.

[50]  L. B. Snoek,et al.  A genome-wide library of CB4856/N2 introgression lines of Caenorhabditis elegans , 2009, Nucleic acids research.

[51]  Evan Z. Macosko,et al.  A huband-spoke circuit drives pheromone attraction and social behaviour in C . elegans , 2009 .

[52]  Y. Indo.  Molecular basis of congenital insensitivity to pain with anhidrosis (CIPA): Mutations and polymorphisms in TRKA (NTRK1) gene encoding the receptor tyrosine kinase for nerve growth factor , 2001, Human mutation.

[53]  Cornelia I Bargmann,et al.  A Distributed Chemosensory Circuit for Oxygen Preference in C. elegans , 2006, PLoS biology.

[54]  M. Tominaga,et al.  Nociception and TRP Channels. , 2004, Current drug targets. CNS and neurological disorders.

[55]  M. Chalfie,et al.  Targeted cell killing by reconstituted caspases , 2007, Proceedings of the National Academy of Sciences.