Feeding is inhibited by sublethal concentrations of toxicants and by heat stress in the nematodeCaenorhabditis elegans: Relationship to the cellular stress response
| Autor: | E. P. M. Candido, David R. Jones |
|---|---|
| Rok vydání: | 1999 |
| Předmět: |
Pharyngeal pumping
Pharynx General Medicine Biology biology.organism_classification Median lethal dose Cell biology Toxicology chemistry.chemical_compound medicine.anatomical_structure chemistry Cellular stress response Heat shock protein medicine Animal Science and Zoology Heat shock Caenorhabditis elegans Salicylic acid |
| Zdroj: | Journal of Experimental Zoology. 284:147-157 |
| ISSN: | 1097-010X 0022-104X |
| DOI: | 10.1002/(sici)1097-010x(19990701)284:2<147::aid-jez4>3.0.co;2-z |
| Popis: | We report that the free-living nematode Caenorhabditis elegans can respond to a variety of stressors (compounds known to induce the production of cellular stress proteins in model biological systems), by ceasing pharyngeal pumping. This phenomenon results in both a reduction in intake of the stressor and a cessation of feeding. The effect of stressors can therefore be conveniently assayed by monitoring the decrease in the density of the bacterial food in liquid cultures of nematodes. A great range of stressors induced this response including alcohols, heavy metals, sulfhydryl-reactive compounds, salicylate, and heat. For several of these stressors, inhibition of pharyngeal pumping occurred at stressor concentrations below the threshold required for the induction of the 16-kDa heat shock proteins. Salicylate, which did not induce 16-kDa heat shock proteins at any concentration, nevertheless inhibited pharyngeal pumping. Heat was also inhibitory, at a temperature where 16-kDa heat shock protein production was near maximal. Some compounds caused only a partial inhibition of feeding while with others the effect was complete. Upon removal of the stressor, the nematodes resumed pharyngeal pumping with a residual inhibitory effect that depended on the concentration and type of stressor that had been applied. A number of C. elegans neurosensory mutant strains also exhibited a cessation of pharyngeal pumping when exposed to stressors suggesting that the mechanism underlying this inhibition was not entirely neurosensory and may be intrinsic to the pharynx. In C. elegans and other invertebrates, stress-induced inhibition of feeding may be an important survival mechanism that limits the intake of toxic solutes. |
| Databáze: | OpenAIRE |
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