Abstract
Animals have developed the ability to sense the water content in their habitats, including hygrosensation (sensing humidity in the air) and hydrosensation (sensing the water content in other microenvironments), and they display preferences for specific water contents that influence their mating, reproduction and geographic distribution. We developed and employed four quantitative behavioural test paradigms to investigate the molecular and cellular mechanisms underlying sensing the water content in an agar substrate (hydrosensation) and hydrotaxis in Caenorhabditis elegans. By combining a reverse genetic screen with genetic manipulation, optogenetic neuronal manipulation and in vivo Ca2+ imaging, we demonstrate that adult worms avoid the wetter areas of agar plates and hypo-osmotic water droplets. We found that the cGMP signalling pathway in ciliated sensory neurons is involved in hydrosensation and hydrotaxis in Caenorhabditis elegans.
Highlights
Water is an important component of organisms and is essential for life
We identify that the G-protein-coupled receptors (GPCRs)—G-protein—cGMP cyclase (DAF-11)—cGMP— cGMP-gated channel (TAX-2/TAX-4) signalling pathway in the ciliated sensory neuron pairs ASI, ASK and ASJ is involved in hydrosensation and hydrotaxis in C. elegans
To investigate whether C. elegans can sense the water content of agar substrates, we developed and used four behavioural paradigms to examine hydrosensation and hydrotaxis in the worm based on changing the water content of the medium
Summary
Water is an important component of organisms and is essential for life. The environmental water content affects animals’ comfort, physiological homeostasis, behaviour, reproduction, survival and evolution. Insects[4], including Drosophila[1,2,5]; frogs[6]; lizards; toads[7]; rats[8] and cats[9] have sensory neurons that sense the external or internal water content that may, in turn, affect cellular osmolality, volume and stress[10]. Both mechanosensation and hypo-osmosensation are involved in sensing water. We demonstrate that adult C. elegans avoids both the wetter areas and hypo-osmotic water droplets in agar plates We term this sensory modality hydrosensation to emphasise that the worms sense the water content in the substrate. We identify that the GPCR—G-protein—cGMP cyclase (DAF-11)—cGMP— cGMP-gated channel (TAX-2/TAX-4) signalling pathway in the ciliated sensory neuron pairs ASI, ASK and ASJ is involved in hydrosensation and hydrotaxis in C. elegans
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
