In this episode, we explore how Caenorhabditis elegans senses and responds to oxygen — not just by breathing, but by activating a finely tuned cGMP signalling network in real time.
Using genetically encoded biosensors, researchers reveal how rising oxygen levels trigger tonic cGMP and Ca²⁺ responses in O₂-sensing neurons like PQR, and how a web of feedback loops controls these signals to shape behaviour.
We unpack:
The role of soluble guanylate cyclases in detecting O₂
How PDE-1 and PDE-2 form a push-pull system to shape cGMP signals
Surprising individual variability in cGMP responses — even in identical worms
Evidence for cGMP nanodomains and subcellular signal compartmentalisation
How these pathways help worms make behavioural decisions in fluctuating oxygen
📖 Based on the research article:
“In vivo genetic dissection of O₂-evoked cGMP dynamics in a Caenorhabditis elegans gas sensor”
Africa Couto, Shigekazu Oda, Viacheslav O. Nikolaev, Zoltan Soltesz & Mario de Bono
Published in PNAS (2013)
🔗 https://doi.org/10.1073/pnas.1217428110
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