[
International Worm Meeting,
2021]
C. elegans is attracted or repelled by many odorants. The strength of the response varies depending on the odorant and its concentration. However, the response is not 100% even for a strong odorant. For example, isoamyl alcohol, which is one of the strongest attractants for C. elegans, attracts more than 90% of the worms but does not about the remaining 10% in the typical experimental settings. Besides, individual worms behave differently even when they have the same genetic background. It remains unknown in detail how such individual differences in behaviors are created. This study aims to elucidate the unknown mechanisms that make individual behavioral differences in a "homogeneous" group. To quantitatively analyze individual worms' behavior, we developed a system that records worms' behaviors in a 6 cm plate every 0.04 s by using a digital 4K single-lens reflex camera and quantitates the behaviors by using DeepLabCut, a deep learning-based animal tracking software tool. As a first trial, we examined chemotaxis behaviors for isoamyl alcohol by using this system. Our preliminary result showed that the majority of worms (~95%) migrated to the attractant, but a few of them (<5%) were not attracted and continued to move over a wide area in the plate. We plan to investigate the mechanisms that make such individual behavioral differences by combining data-driven and experimental analyses.