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Hypoxia activates a latent circuit for processing gustatory information in C. elegans

Nature Neuroscience volume 13, pages 610614 (2010) | Download Citation

Abstract

Dedicated neuronal circuits enable animals to engage in specific behavioral responses to environmental stimuli. We found that hypoxic stress enhanced gustatory sensory perception via previously unknown circuitry in Caenorhabditis elegans. The hypoxia-inducible transcription factor HIF-1 upregulated serotonin (5-HT) expression in specific sensory neurons that are not normally required for chemosensation. 5-HT subsequently promoted hypoxia-enhanced sensory perception by signaling through the metabotropic G protein–coupled receptor SER-7 in an unusual peripheral neuron, the M4 motor neuron. M4 relayed this information back into the CNS via the FMRFamide-related neuropeptide FLP-21 and its cognate receptor, NPR-1. Thus, physiological detection of hypoxia results in the activation of an additional, previously unrecognized circuit for processing sensory information that is not required for sensory processing under normoxic conditions.

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Acknowledgements

We thank A. Boyanov and G. Baison for technical assistance, Q. Chen for expert microinjection help, I. Greenwald, M. De Bono and members of the Hobert laboratory for comments on the manuscript, and the Caenorhabditis Genetics Center and C. Bargmann for providing strains. This work was supported by the Howard Hughes Medical Institute.

Author information

Affiliations

  1. Department of Biochemistry and Molecular Biophysics, Howard Hughes Medical Institute, Columbia University Medical Center, New York, New York, USA.

    • Roger Pocock
    •  & Oliver Hobert

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Contributions

R.P. initiated this study and conducted all of the experiments. R.P. and O.H. designed and discussed the experiments and wrote the paper.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Roger Pocock.

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DOI

https://doi.org/10.1038/nn.2537

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