Dauer Formation inC. elegansIs Modulated through AWC and ASI-Dependent Chemosensation

Abstract

Negi for routine help, Anupreet Saini for help with genotyping and chemotaxis assays and the IISER Mohali Confocal facility for use of the confocal microscope.

AWC mediated behavioral plasticity inC. elegansagainstSalmonellaTyphimurium infection

“…[4, 16, 30, 31]]. ceh-36 [CEH-36 is a transcription factor playing an essential role in the terminal differentiation of AWC neuron, and mutation to this gene lead to defective responses towards AWC sensed odorant [32]]. Besides, we also measured mRNA expression of the daf-11 gene since AWC neuron utilized a major signal transduction pathway through the DAF-11 guanylyl cyclase pathway and mutation in daf-11 gene in animals exhibiting defective responses toward AWC sensed odorant [4, 33, 34].…”

“…Caenorhabditis elegans (C. elegans) is free-living soil nematode commonly found in complex environments (decaying vegetation, rotten fruits and compost) in a close association with both pathogenic and non-pathogenic microorganisms which build a hostile situation for worm's optimum survival. However, C. elegans have well-developed chemosensory system with 302 neurons that enable the worms to locate food and sense danger or other animals in their natural habitat [2,3]. Such chemosensory neurons will translate the chemical cues perceived from its environment and initiate neuroendocrine signaling which allow worms to discriminate between edible food and pathogen contaminated food and drive physical avoidance and also lead to developmental decision in worms [4,5].…”

“…]. ceh-36 [CEH-36 is a transcription factor playing an essential role in the terminal differentiation of AWC neuron, and mutation to this gene lead to defective responses towards AWC sensed odorant[32]]. Besides, we also measured mRNA expression of the daf-11 gene…”

Escape steering by cholecystokinin peptidergic signaling

“…C. elegans NLP-18-CKR-1 signaling involves the gustatory sensory neuron and escape response. NLP-18's primary neuronal source, the ASI neurons, is known to secrete hormone-like peptides insulin and transforming growth factor b (TGF-b) (Pandey et al, 2021;You et al, 2008). There might be potential conservation of CKR-1's role in neural circuits.…”

“…The steering behavior is regulated by sensory neurons, such as ASI (Figure 7G), that may not directly evoke escape responses. ASIs are gustatory and multimodal, known for their roles in food-related modulation, including insulin-related chemotaxis behaviors and dauer formation (Bargmann and Horvitz, 1991;Pandey et al, 2021;You et al, 2008). ASIs suppress U turn frequency by inhibiting the olfactory neuron AWC in the absence of food (Gray et al, 2005), in addition transducing noxious cues during nociception (Guo et al, 2015).…”