EvoLunch Seminar: Wilfrid Jean Louis (ISTA)
EvoLunch Seminar
Tuning through elevation: natural variation in oxygen-sensing behavior across wild C. elegans populations
"Tuning through elevation: natural variation in oxygen-sensing behavior across wild C. elegans populations"
11:00 CET
Mondi 2ab, Central Building, ISTA
Hybrid Meeting (for zoom link, email evolunch.seminar@ist.ac.at)
Oxygen (O2) availability declines steeply with altitude and powerfully shapes animal physiology and behavior. This project studies how natural isolates of the cosmopolitan nematode Caenorhabditis elegans tune their behavior to local oxygen conditions across altitude. C. elegans thrives in rotting fruit and vegetation, where O2 is low, and continuously monitors ambient O2 to detect exposure to the surface, mounting a persistent escape response above ~19–21% O2. In wild isolates from low-altitude environments, this response is sharply tuned to trigger near sea-level O2 concentrations (21%). Preliminary observations suggest that isolates from high-altitude environments may retune this response toward lower O2 thresholds, matching their local atmosphere. Here we combine behavioral assays, population genomics, and neural activity imaging to (i) map the O2 concentration that triggers the escape/arousal response across a panel of wild isolates spanning a range of native altitudes, (ii) use Ca2+ imaging to test whether oxygen-responsive neurons differ in tuning between isolates adapted to different altitudes, and (iii) identify natural genetic variation associated with these behavioral differences. C. elegans offers a uniquely powerful system for this work, combining natural diversity, a compact and genetically accessible oxygen-sensing circuit, and experimental tractability allowing us to ask whether distinct high-altitude populations converge on the same genetic solution or arrive at their adaptation independently.