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bioRxiv · 10.64898/2026.03.09.710502

MEC-2/Stomatin is required for aversive behaviour but dispensable for prey detection in the predatory nematode Pristionchus pacificus

Roca, M.·Lightfoot, J. W.
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Abstract

Sensory systems provide animals with essential information about their environment and are critical for generating appropriate behaviours. Mechanosensation is a fundamental component of this sensory repertoire, and disruption of mechanosensory pathways can have severe functional consequences. In the nematode Caenorhabditis elegans, mechanosensory circuits have been extensively characterized and mediate touch-driven navigation and avoidance. These circuits rely on conserved molecular components including the stomatin-like protein MEC-2 along with MEC-6, which function together in the mechanotransduction complex. In contrast, the predatory nematode Pristionchus pacificus has repurposed mechanosensory pathways to also enable prey detection, a derived ecological behaviour. As we previously demonstrated that Ppa-mec-6 is required for efficient predation, here we assessed if Ppa-mec-2 plays a similar role in P. pacificus prey detection. We find that while Ppa-mec-2 is required for the aversive touch response, it is dispensable for prey detection. This functional divergence reflects differential neuronal expression as Ppa-mec-2 is absent from the IL2 neurons that mediate prey detection and also robustly express Ppa-mec-6. These findings reveal that partitioning of mechanosensory components across neuronal types enables functional specialization, demonstrating how conserved sensory machinery can support distinct behavioural functions across evolution.

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Roca, M., Lightfoot, J. W.. 2026-03-11. MEC-2/Stomatin is required for aversive behaviour but dispensable for prey detection in the predatory nematode Pristionchus pacificus. https://doi.org/10.64898/2026.03.09.710502

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