Caprini, Davide et al. (2021) International Worm Meeting "The C.elegans AWCON olfactory neuron responds to tangential component of mechanical stimuli and its activation is mediated by TAX-4 cGMP-gated cation channel"

Nicoletti, Martina, Ferrarese, Giuseppe, Lanza, Enrico, Caprini, Davide, Chiodo, Letizia, Folli, Viola, Schwartz, Silvia, Lucente, Valeria, Milanetti, Edoardo

[International Worm Meeting, 2021]

The two major sensory modalities of C.elegans are chemosensation and mechanosensation. Calcium imaging experiments have previously suggested that these two modalities are functionally segregated. Here, we demonstrate that AWCON olfactory neuron, which plays a crucial role in chemosensation, does not only respond to chemicals but also to mechanical stimuli. Touch senses mechanical stimuli, comprising two components: pressure and shear stress. Previous studies assessing mechanosensation in C.elegans have always referred to pressure stimuli only. In this work, we shown that C.elegans senses also the tangential component of mechanical stimuli by recruiting the AWC neuron, and we give evidence that this ability may depend on specific odor receptors. We further show that the mechanosensitivity of AWC neurons has an intrinsic nature rather than a synaptic origin and the calcium transient response is mediated by TAX-4 cGMP-gated cation channel, suggesting the involvement of one or more "odorant" receptors in AWC mechano-transduction. Moreover, calcium events show a bistable neuronal regime structurally different from the typical calcium response to a chemical stimulus. The observed bistability indicates that AWCON adopts distinct sensory strategies for chemo-and mechanosensation, adapting molecules and receptors to convert chemical and mechanical stimuli into different cellular signaling.