Polymodal Functionality of C. elegans OLL Neurons in Mechanosensation and Thermosensation

Abstract

Sensory modalities are important for survival but the molecular mechanisms remain challenging due to the polymodal functionality of sensory neurons. Here, we report the C. elegans outer labial lateral (OLL) sensilla sensory neurons respond to touch and cold. Mechanosensation of OLL neurons resulted in cell-autonomous mechanically-evoked Ca2+ transients and rapidly-adapting mechanoreceptor currents with a very short latency. Mechanotransduction of OLL neurons might be carried by a novel Na+ conductance channel, which is insensitive to amiloride. The bona fide mechano-gated Na+-selective degenerin/epithelial Na+ channels, TRP-4, TMC, and Piezo proteins are not involved in this mechanosensation. Interestingly, OLL neurons also mediated cold but not warm responses in a cell-autonomous manner. We further showed that the cold response of OLL neurons is not mediated by the cold receptor TRPA-1 or the temperature-sensitive glutamate receptor GLR-3. Thus, we propose the polymodal functionality of OLL neurons in mechanosensation and cold sensation.

Protocol for glial Ca2+ imaging in C. elegans following chemical, mechanical, or optogenetic stimulation

“…Set the amplifier to give a pulse at a specific time point. The piezoelectric actuator can transform 1 volt pulse to 4.5 μm mechanical stimuli ( Fan et al., 2021 ). Drop 20–40 μL bath solution in the middle of the prepared sylgard round coverslip.…”