scholarly journals C. elegans PEZO-1 is a Mechanosensitive Channel Involved in Food Sensation

2021 ◽  
Author(s):  
Jonathan R.M. Millet ◽  
Luis O Romero ◽  
Jungsoo Lee ◽  
Valeria Vásquez

PIEZO channels are force sensors essential for physiological processes including baroreception and proprioception. The Caenorhabditis elegans genome encodes an ortholog gene of the Piezo family, pezo-1, expressed in several tissues including the pharynx. This myogenic pump is an essential component of the C. elegans alimentary canal whose contraction and relaxation are modulated by mechanical stimulation elicited by food content. Whether pezo-1 encodes a mechanosensitive channel and contributes to pharyngeal function remains unknown. Here, we leverage genome editing, genetics, microfluidics, and electropharyngeogram recordings to establish that pezo-1 is expressed in the pharynx, including a proprioceptive-like neuron, and regulates pharyngeal function. Knockout (KO) and gain-of-function (GOF) mutants reveal that pezo-1 is involved in fine-tuning pharyngeal pumping frequency, sensing osmolarity, and food quality. Using pressure-clamp experiments in primary C. elegans embryo cultures, we determine that pezo-1 KO cells do not display mechanosensitive currents, whereas cells expressing wild-type or GOF PEZO-1 exhibit mechanosensitivity. Moreover, infecting the Spodoptera frugiperda cell line with a baculovirus containing the pezo-1 isoform G (among the longest isoforms) demonstrates that pezo-1 encodes a mechanosensitive channel. Our findings reveal that pezo-1 is a mechanosensitive ion channel that regulates food sensation in worms.

2021 ◽  
Vol 154 (1) ◽  
Author(s):  
Jonathan R.M. Millet ◽  
Luis O. Romero ◽  
Jungsoo Lee ◽  
Briar Bell ◽  
Valeria Vásquez

PIEZO channels are force sensors essential for physiological processes, including baroreception and proprioception. The Caenorhabditis elegans genome encodes an orthologue gene of the Piezo family, pezo-1, which is expressed in several tissues, including the pharynx. This myogenic pump is an essential component of the C. elegans alimentary canal, whose contraction and relaxation are modulated by mechanical stimulation elicited by food content. Whether pezo-1 encodes a mechanosensitive ion channel and contributes to pharyngeal function remains unknown. Here, we leverage genome editing, genetics, microfluidics, and electropharyngeogram recording to establish that pezo-1 is expressed in the pharynx, including in a proprioceptive-like neuron, and regulates pharyngeal function. Knockout (KO) and gain-of-function (GOF) mutants reveal that pezo-1 is involved in fine-tuning pharyngeal pumping frequency, as well as sensing osmolarity and food mechanical properties. Using pressure-clamp experiments in primary C. elegans embryo cultures, we determine that pezo-1 KO cells do not display mechanosensitive currents, whereas cells expressing wild-type or GOF PEZO-1 exhibit mechanosensitivity. Moreover, infecting the Spodoptera frugiperda cell line with a baculovirus containing the G-isoform of pezo-1 (among the longest isoforms) demonstrates that pezo-1 encodes a mechanosensitive channel. Our findings reveal that pezo-1 is a mechanosensitive ion channel that regulates food sensation in worms.


2021 ◽  
Vol 154 (1) ◽  
Author(s):  
Ben Short

JGP study finds that the C. elegans orthologue of the PIEZO family is a mechanosensitive ion channel that regulates pharyngeal pumping and food sensation.


2022 ◽  
Author(s):  
Thomas J O'Brien

The pharynx is a is a neuromuscular pump found at the anterior end of the alimentary tract, consisting of 20 muscles and 20 neurons. A proper feeding rate in worms is coordinated by the precise timing of pharyngeal movements, with one complete cycle of synchronous contraction and relaxation of the corpus and terminal bulb termed a “pump”. A simple way to measure C. elegans feeding is to count how many times worms pump in a minute (pumps per minute). Movement of the grinder (in the terminal bulb) can easily be observed using a stereomicroscope, and because cycles of contraction/relaxation are synchronised along the pharynx, pumps per minute can be measured simply by counting grinder movements.


2021 ◽  
Author(s):  
Isaac Ravi Brenner ◽  
David M. Raizen ◽  
Christopher Fang-Yen

AbstractThe nematode C. elegans uses rhythmic muscle contractions and relaxations called pumps to filter, transport, and crush food particles. A number of feeding mutants have been identified, including those with slow pharyngeal pumping rate, weak muscle contraction, defective muscle relaxation, and defective grinding of bacteria. Many aspects of these pharyngeal behavioral defects and how they affect pharyngeal function are not well understood. For example, the behavioral deficits underlying inefficient particle transport in ‘slippery’ mutants have been unclear. Here we use high speed video microscopy to describe pharyngeal pumping behaviors and particle transport in wild-type animals and in feeding mutants. Different ‘slippery’ mutants exhibit distinct defects including weak isthmus contraction, failure to trap particles in the anterior isthmus, and abnormal timing of contraction and relaxation in pharyngeal compartments. Our results show that multiple deficits in pharyngeal timing or contraction can cause defects in particle transport.


Genetics ◽  
2002 ◽  
Vol 161 (1) ◽  
pp. 133-142 ◽  
Author(s):  
Celine Moorman ◽  
Ronald H A Plasterk

AbstractThe sgs-1 (suppressor of activated Gαs) gene encodes one of the four adenylyl cyclases in the nematode C. elegans and is most similar to mammalian adenylyl cyclase type IX. We isolated a complete loss-of-function mutation in sgs-1 and found it to result in animals with retarded development that arrest in variable larval stages. sgs-1 mutant animals exhibit lethargic movement and pharyngeal pumping and (while not reaching adulthood) have a mean life span that is >50% extended compared to wild type. An extensive set of reduction-of-function mutations in sgs-1 was isolated in a screen for suppressors of a neuronal degeneration phenotype induced by the expression of a constitutively active version of the heterotrimeric Gαs subunit of C. elegans. Although most of these mutations change conserved residues within the catalytic domains of sgs-1, mutations in the less-conserved transmembrane domains are also found. The sgs-1 reduction-of-function mutants are viable and have reduced locomotion rates, but do not show defects in pharyngeal pumping or life span.


PLoS Genetics ◽  
2013 ◽  
Vol 9 (6) ◽  
pp. e1003618 ◽  
Author(s):  
Jingyan Zhang ◽  
Xia Li ◽  
Angela R. Jevince ◽  
Liying Guan ◽  
Jiaming Wang ◽  
...  

2021 ◽  
Author(s):  
Matthew J Gadenne ◽  
Iris Hardege ◽  
Djordji Suleski ◽  
Paris Jaggers ◽  
Isabel Beets ◽  
...  

Sexual dimorphism occurs where different sexes of the same species display differences in characteristics not limited to reproduction. For the nematode Caenorhabditis elegans, in which the complete neuroanatomy has been solved for both hermaphrodites and males, sexually dimorphic features have been observed both in terms of the number of neurons and in synaptic connectivity. In addition, male behaviours, such as food-leaving to prioritise searching for mates, have been attributed to neuropeptides released from sex-shared or sex-specific neurons. In this study, we show that the lury-1 neuropeptide gene shows a sexually dimorphic expression pattern; being expressed in pharyngeal neurons in both sexes but displaying additional expression in tail neurons only in the male. We also show that lury-1 mutant animals show sex differences in feeding behaviours, with pharyngeal pumping elevated in hermaphrodites but reduced in males. LURY-1 also modulates male mating efficiency, influencing motor events during contact with a hermaphrodite. Our findings indicate sex-specific roles of this peptide in feeding and reproduction in C. elegans, providing further insight into neuromodulatory control of sexually dimorphic behaviours.


Author(s):  
Benjamin W. Harding ◽  
Jonathan J. Ewbank

The simple notion ‘infection causes an immune response' is being progressively refined as it becomes clear that immune mechanisms cannot be understood in isolation, but need to be considered in a more global context with other cellular and physiological processes. In part, this reflects the deployment by pathogens of virulence factors that target diverse cellular processes, such as translation or mitochondrial respiration, often with great molecular specificity. It also reflects molecular cross-talk between a broad range of host signalling pathways. Studies with the model animal C. elegans have uncovered a range of examples wherein innate immune responses are intimately connected with different homeostatic mechanisms, and can influence reproduction, ageing and neurodegeneration, as well as various other aspects of its biology. Here we provide a short overview of a number of such connections, highlighting recent discoveries that further the construction of a fully integrated view of innate immunity.


2019 ◽  
Vol 317 (5) ◽  
pp. C953-C963 ◽  
Author(s):  
Fengling Yuan ◽  
Jiejun Zhou ◽  
Lingxiu Xu ◽  
Wenxin Jia ◽  
Lei Chun ◽  
...  

GABA, a prominent inhibitory neurotransmitter, is best known to regulate neuronal functions in the nervous system. However, much less is known about the role of GABA signaling in other physiological processes. Interestingly, recent work showed that GABA signaling can regulate life span via a metabotropic GABAB receptor in Caenorhabditis elegans. However, the role of other types of GABA receptors in life span has not been clearly defined. It is also unclear whether GABA signaling regulates health span. Here, using C. elegans as a model, we systematically interrogated the role of various GABA receptors in both life span and health span. We find that mutations in four different GABA receptors extend health span by promoting resistance to stress and pathogen infection and that two such receptor mutants also show extended life span. Different GABA receptors engage distinct transcriptional factors to regulate life span and health span, and even the same receptor regulates life span and health span via different transcription factors. Our results uncover a novel, profound role of GABA signaling in aging in C. elegans, which is mediated by different GABA receptors coupled to distinct downstream effectors.


2018 ◽  
Author(s):  
Jürgen Jänes ◽  
Yan Dong ◽  
Michael Schoof ◽  
Jacques Serizay ◽  
Alex Appert ◽  
...  

AbstractAn essential step for understanding the transcriptional circuits that control development and physiology is the global identification and characterization of regulatory elements. Here we present the first map of regulatory elements across the development and ageing of an animal, identifying 42,245 elements accessible in at least one C. elegans stage. Based on nuclear transcription profiles, we define 15,714 protein-coding promoters and 19,231 putative enhancers, and find that both types of element can drive orientation-independent transcription. Additionally, hundreds of promoters produce transcripts antisense to protein coding genes, suggesting involvement in a widespread regulatory mechanism. We find that the accessibility of most elements is regulated during development and/or ageing and that patterns of accessibility change are linked to specific developmental or physiological processes. The map and characterization of regulatory elements across C. elegans life provides a platform for understanding how transcription controls development and ageing.


Sign in / Sign up

Export Citation Format

Share Document