1999/08/31 by Nicole Wittenburg, Ralf Baumeister · 3 citations
Biochemistry, Genetics and Molecular Biology · Neuroscience · Psychology · #Aversive Stimulus #Avoidance behaviour #Biology #Caenorhabditis elegans #Circadian rhythm and melatonin #Escape response #Gene #Genetics #Genetics, Aging, and Longevity in Model Organisms #Neurobiology and Insect Physiology Research #Neuroscience #Nociception #Noxious stimulus #Psychology #Reflex #Sensory system #Stimulus (psychology)
paper · doi:10.1073/pnas.96.18.10477
openalex publication_date 1999/08/31 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/11
Upon perception of a noxious stimulus, an organism executes defense mechanisms, such as escape responses. The molecular basis of these mechanisms is poorly understood. In this paper we show that upon exposure to noxious temperature, Caenorhabditis elegans reacts by a withdrawal reflex. To analyze this thermal avoidance behavior, we developed a laser-based assay to quantify the response. The escape reflex can be observed in 98% of the adult animals, but is not executed in animals in diapause. The thermal avoidance response differs significantly from the thermotaxis behavior that is based on the perception of physiological temperature. It involves different neurons and is influenced by mutations in distinct genes. As in mammals, the strength of the thermal avoidance response is increased by application of capsaicin, the pungent ingredient in chili peppers. We find that thermal avoidance is strongly reduced in mutants affecting the neural transmission modulated by glutamate and neuropeptides as well as in mutants affecting the structure and function of sensory neurons. We suggest that the study of this nociceptive behavior in C. elegans can be used to understand the genetic and molecular basis of thermal nociception.