Why do C. elegans lay eggs only when food is around? In this episode, we explore a newly uncovered neuromodulatory circuit that links food detection to reproductive behaviour using a clever form of disinhibition. At the heart of this is the AVK interneuron — silenced by dopamine when food is present — which normally blocks egg-laying until conditions are right.
We unpack:
How AVK neurons act as gatekeepers for egg-laying behaviour
Dopamine from food-sensing neurons inhibits AVKs via DOP-3 receptors
AVKs release a cocktail of neuropeptides (PDF-1, NLP-10, NLP-21) that modulate downstream AIY neurons
Functional imaging, CRISPR mutants, and optogenetics map the full food-to-egg pathway
How this reveals general principles of neuromodulation and disinhibition
📖 Based on the research article:
“Food sensing controls C. elegans reproductive behavior by neuromodulatory disinhibition”
Yen-Chih Chen, Kara E. Zang, Hassan Ahamed, Niels Ringstad
Published in Science Advances (2025)
🔗 https://doi.org/10.1126/sciadv.adu5829
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