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bioRxiv · 10.1101/2021.07.26.451501

Distinct mechanisms underlie H2O2 sensing in C. elegans head and tail

Quintin, S.·Aspert, T.·Charvin, G.
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Abstract

Environmental oxidative stress threatens cellular integrity and should therefore be avoided by living organisms. Yet, relatively little is known about environmental oxidative stress perception. Here, using microfluidics, we showed that like I2 pharyngeal neurons, the tail phasmid PHA neurons function as oxidative stress sensing neurons in C. elegans, but display different responses to H2O2 and light. We uncovered that different but related receptors, GUR-3 and LITE-1, mediate H2O2 signaling in I2 and PHA neurons. Still, the peroxiredoxin PRDX-2 is essential for both, and might promote H2O2-mediated receptor activation. Our work demonstrates that C. elegans can sense a broad range of oxidative stressors using partially distinct H2O2 signaling pathways in head and tail sensillae, and paves the way for further understanding of how the integration of these inputs translates into the appropriate behavior. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=121 SRC="FIGDIR/small/451501v4_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@130c30eorg.highwire.dtl.DTLVardef@55fbeeorg.highwire.dtl.DTLVardef@10edcfforg.highwire.dtl.DTLVardef@cf0ab7_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Quintin, S., Aspert, T., Charvin, G.. 2021-07-26. Distinct mechanisms underlie H2O2 sensing in C. elegans head and tail. https://doi.org/10.1101/2021.07.26.451501

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