Cholinergic signalling at the body wall neuromuscular junction distally inhibits feeding behaviour in C. elegans

Abstract Using a pan-neuronal GFP marker, a morphological screen was performed to detect Caenorhabditis elegans larval lethal mutants with severely disorganized major nerve cords. We recovered and characterized 21 mutants that displayed displacement or detachment of the ventral nerve cord from the body wall (Ven: ventral cord abnormal). Six mutations defined three novel genetic loci: ven-1, ven-2, and ven-3. Fifteen mutations proved to be alleles of previously identified muscle attachment/positioning genes, mup-4, mua-1, mua-5, and mua-6. All the mutants also displayed muscle attachment/positioning defects characteristic of mua/mup mutants. The pan-neuronal GFP marker also revealed that mutants of other mua/mup loci, such as mup-1, mup-2, and mua-2, exhibited the Ven defect. The hypodermis, the excretory canal, and the gonad were morphologically abnormal in some of the mutants. The pleiotropic nature of the defects indicates that ven and mua/mup genes are required generally for the maintenance of attachment of tissues to the body wall in C. elegans.

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Positioning and maintenance of embryonic body wall muscle attachments in C. elegans requires the mup-1 gene

Development ◽

10.1242/dev.111.3.667 ◽

1991 ◽

Vol 111 (3) ◽

pp. 667-681 ◽

Cited By ~ 3

Author(s):

P.Y. Goh ◽

T. Bogaert

Keyword(s):

Extracellular Matrix ◽

Body Wall ◽

Early Stage ◽

Muscle Growth ◽

The Body ◽

Body Wall Muscle ◽

C Elegans ◽

Extracellular Matrix Molecule ◽

Extracellular Matrix Components ◽

Body Wall Muscles

As part of a general study of genes specifying a pattern of muscle attachments, we identified and genetically characterised mutants in the mup-1 gene. The body wall muscles of early stage mup-1 embryos have a wild-type myofilament pattern but may extend ectopic processes. Later in embryogenesis, some body wall muscles detach from the hypodermis. Genetic analysis suggests that mup-1 has both a maternal and a zygotic component and is not required for postembryonic muscle growth and attachment. mup-1 mutants are suppressed by mutations in several genes that encode extracellular matrix components. We propose that mup-1 may encode a cell surface/extracellular matrix molecule required both for the positioning of body wall muscle attachments in early embryogenesis and the subsequent maintenance of these attachments to the hypodermis until after cuticle synthesis.

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LONGEVITY OVER THE COUNTER: INVESTIGATING THE EFFECTS OF COMMON DIETARY SUPPLEMENTS ON AGING

Innovation in Aging ◽

10.1093/geroni/igz038.384 ◽

2019 ◽

Vol 3 (Supplement_1) ◽

pp. S102-S103

Author(s):

Ben Blue ◽

Elena Vayndorf ◽

Matt Kaeberlein

Keyword(s):

Body Wall ◽

Video Recording ◽

The Body ◽

Limiting Factor ◽

Time Of Death ◽

Image Capture ◽

Over The Counter ◽

C Elegans ◽

Short Lifespan ◽

Age Related

Abstract C. elegans has been a workhorse within the field of aging biology for several decades due to its short lifespan, easy culturing, and robust genetic tools. However, the limiting factor in using C. elegans has been that throughput was constrained by the time and effort needed to manually check the worms for signs of life during longitudinal studies. By using the WormBot, a robotic image capture platform, we are able to successfully screen a wide array of compounds for their effects upon C. elegans lifespan. A single WormBot can monitor 144 individual experiments simultaneously and allows for accurate time of death calls. Here we present data generated with the WormBot that includes a screen of compounds from a wide array of natural and synthetic products that are often available as over-the-counter supplements. In order to better examine the effects of these widely-used compounds upon the aging process and an age-associated disease we examined longevity in a wildtype strain of C. elegans as well as an engineered strain that expresses human Aβ protein in the body wall muscle. The age-related pathogenesis of the Aβ-expressing strain is a progressive paralysis that can be halted with treatment of known effectors of Alzheimer’s disease. As such, we screened our battery of compounds with this strain to determine which compounds have a significant affect on delaying Aβ-associated paralysis. Lastly, using the WormBot’s ability to capture video recording, we examine how each compound affects mobility as animals age.

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The effect of the anthelmintic emodepside at the neuromuscular junction of the parasitic nematode Ascaris suum

Parasitology ◽

10.1017/s0031182002002639 ◽

2003 ◽

Vol 126 (1) ◽

pp. 79-86 ◽

Cited By ~ 26

Author(s):

J. WILLSON ◽

K. AMLIWALA ◽

A. HARDER ◽

L. HOLDEN-DYE ◽

R. J. WALKER

Keyword(s):

Neuromuscular Junction ◽

Body Wall ◽

Parasitic Nematode ◽

Ascaris Suum ◽

Muscle Relaxation ◽

The Body ◽

The Novel ◽

Similar Action ◽

Inhibitory Neurotransmitter ◽

Electrophysiological Recordings

Here we report on the action of the novel cyclo-depsipeptide anthelmintic, emodepside, on the body wall muscle of the parasitic nematode, Ascaris suum. Emodepside caused (i) muscle relaxation, (ii) inhibition of muscle contraction elicited by either acetylcholine (ACh), or the neuropeptide, AF2 (KHEYLRFamide) and (iii) a rapid relaxation of muscle tonically contracted by ACh. The inhibitory action of emodepside on the response to ACh was not observed in a denervated muscle strip, indicating that it may exert this action through the nerve cord, and not directly on the muscle. Electrophysiological recordings showed emodepside elicited a Ca++-dependent hyperpolarization of muscle cells. Furthermore, the response to emodepside was dependent on extracellular K+, similar to the action of the inhibitory neuropeptides PF1 and PF2 (SDPNFLRFamide and SADPNFLRFamide). Thus emodepside may act at the neuromuscular junction to stimulate release of an inhibitory neurotransmitter or neuromodulator, with a similar action to the PF1/PF2 neuropeptides.

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Cholinergic signalling at the body wall neuromuscular junction couples to distal inhibition of feeding in C. elegans

10.1101/2021.02.12.430967 ◽

2021 ◽

Author(s):

Patricia G. Izquierdo ◽

Thibana Thisainathan ◽

James H. Atkins ◽

Christian J. Lewis ◽

John E.H. Tattersall ◽

...

Keyword(s):

Body Wall ◽

Neuromuscular Junctions ◽

Model Organism ◽

Inhibitory Effect ◽

The Body ◽

Body Wall Muscle ◽

Cholinergic Transmission ◽

Systematic Screening ◽

C Elegans ◽

Pharyngeal Pumping

AbstractComplex biological functions within organisms are frequently orchestrated by systemic communication between tissues. In the model organism C. elegans, the pharyngeal and body wall neuromuscular junctions are two discrete structures that control feeding and locomotion, respectively. These distinct tissues are controlled by separate, well-defined neural circuits. Nonetheless, the emergent behaviours, feeding and locomotion, are coordinated to guarantee the efficiency of food intake. We show that pharmacological hyperactivation of cholinergic transmission at the body wall muscle reduces the rate of pumping behaviour. This was evidenced by a systematic screening of the cholinesterase inhibitor aldicarb’s effect on the rate of pharyngeal pumping on food in mutant worms. The screening revealed that the key determinant of the inhibitory effect of aldicarb on pharyngeal pumping is the L-type nicotinic acetylcholine receptor expressed in body wall muscle. This idea was reinforced by the observation that selective hyperstimulation of the body wall muscle L-type receptor by the agonist levamisole inhibited pumping. Overall, our results reveal that body wall cholinergic transmission controls locomotion and simultaneously couples a distal inhibition of feeding.

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Three-dimensional simulation of the Caenorhabditis elegans body and muscle cells in liquid and gel environments for behavioural analysis

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2017.0376 ◽

2018 ◽

Vol 373 (1758) ◽

pp. 20170376 ◽

Cited By ~ 10

Author(s):

Andrey Palyanov ◽

Sergey Khayrulin ◽

Stephen D. Larson

Keyword(s):

Caenorhabditis Elegans ◽

Muscle Activation ◽

Body Wall ◽

Particle System ◽

Three Dimensional ◽

Muscle Cells ◽

The Body ◽

C Elegans ◽

Muscle Activation Patterns ◽

Simulation Engine

To better understand how a nervous system controls the movements of an organism, we have created a three-dimensional computational biomechanical model of the Caenorhabditis elegans body based on real anatomical structure. The body model is created with a particle system–based simulation engine known as Sibernetic, which implements the smoothed particle–hydrodynamics algorithm. The model includes an elastic body-wall cuticle subject to hydrostatic pressure. This cuticle is then driven by body-wall muscle cells that contract and relax, whose positions and shape are mapped from C. elegans anatomy, and determined from light microscopy and electron micrograph data. We show that by using different muscle activation patterns, this model is capable of producing C. elegans -like behaviours, including crawling and swimming locomotion in environments with different viscosities, while fitting multiple additional known biomechanical properties of the animal. This article is part of a discussion meeting issue ‘Connectome to behaviour: modelling C. elegans at cellular resolution’.

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Calsequestrin, a calcium sequestering protein localized at the sarcoplasmic reticulum, is not essential for body-wall muscle function in Caenorhabditis elegans

Journal of Cell Science ◽

10.1242/jcs.113.22.3947 ◽

2000 ◽

Vol 113 (22) ◽

pp. 3947-3958 ◽

Cited By ~ 2

Author(s):

J.H. Cho ◽

Y.S. Oh ◽

K.W. Park ◽

J. Yu ◽

K.Y. Choi ◽

...

Keyword(s):

Sarcoplasmic Reticulum ◽

Calcium Binding ◽

Body Wall ◽

Functional Characterization ◽

The Body ◽

Body Wall Muscle ◽

C Elegans ◽

Muscle Formation ◽

Body Wall Muscles

Calsequestrin is the major calcium-binding protein of cardiac and skeletal muscles whose function is to sequester Ca(2+)in the lumen of the sarcoplasmic reticulum (SR). Here we describe the identification and functional characterization of a C. elegans calsequestrin gene (csq-1). CSQ-1 shows moderate similarity (50% similarity, 30% identity) to rabbit skeletal calsequestrin. Unlike mammals, which have two different genes encoding cardiac and fast-twitch skeletal muscle isoforms, csq-1 is the only calsequestrin gene in the C. elegans genome. We show that csq-1 is highly expressed in the body-wall muscles, beginning in mid-embryogenesis and maintained through the adult stage. In body-wall muscle cells, CSQ-1 is localized to sarcoplasmic membranes surrounding sarcomeric structures, in the regions where ryanodine receptors (UNC-68) are located. Mutation in UNC-68 affects CSQ-1 localization, suggesting that the two possibly interact in vivo. Genetic analyses of chromosomal deficiency mutants deleting csq-1 show that CSQ-1 is not essential for initiation of embryonic muscle formation and contraction. Furthermore, double-stranded RNA injection resulted in animals completely lacking CSQ-1 in body-wall muscles with no observable defects in locomotion. These findings suggest that although CSQ-1 is one of the major calcium-binding proteins in the body-wall muscles of C. elegans, it is not essential for body-wall muscle formation and contraction.

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Quantitative fluorescence imaging of mitochondria in body wall muscles of Caenorhabditis elegans under hyperglycemic conditions using a microfluidic chip

Integrative Biology ◽

10.1093/intbio/zyaa011 ◽

2020 ◽

Vol 12 (6) ◽

pp. 150-160 ◽

Cited By ~ 1

Author(s):

Samuel Sofela ◽

Sarah Sahloul ◽

Sukanta Bhattacharjee ◽

Ambar Bose ◽

Ushna Usman ◽

...

Keyword(s):

Caenorhabditis Elegans ◽

Fluorescence Imaging ◽

Microfluidic Device ◽

Microfluidic Chip ◽

Body Wall ◽

The Body ◽

C Elegans ◽

Technological Advantage ◽

Body Wall Muscles ◽

Quantitative Fluorescence

Abstract Type 2 diabetes is the most common metabolic disease, and insulin resistance plays a role in the pathogenesis of the disease. Because completely functional mitochondria are necessary to obtain glucose-stimulated insulin from pancreatic beta cells, dysfunction of mitochondrial oxidative pathway could be involved in the development of diabetes. As a simple animal model, Caenorhabditis elegans renders itself to investigate such metabolic mechanisms because it possesses insulin/insulin-like growth factor-1 signaling pathway similar to that in humans. Currently, the widely spread agarose pad-based immobilization technique for fluorescence imaging of the mitochondria in C. elegans is laborious, batchwise, and does not allow for facile handling of the worm. To overcome these technical challenges, we have developed a single-channel microfluidic device that can trap a C. elegans and allow to image the mitochondria in body wall muscles accurately and in higher throughput than the traditional approach. In specific, our microfluidic device took advantage of the proprioception of the worm to rotate its body in a microfluidic channel with an aspect ratio above one to gain more space for its undulation motion that was favorable for quantitative fluorescence imaging of mitochondria in the body wall muscles. Exploiting this unique feature of the microfluidic chip-based immobilization and fluorescence imaging, we observed a significant decrease in the mitochondrial fluorescence intensity under hyperglycemic conditions, whereas the agarose pad-based approach did not show any significant change under the same conditions. A machine learning model trained with these fluorescence images from the microfluidic device could classify healthy and hyperglycemic worms at high accuracy. Given this significant technological advantage, its easiness of use and low cost, our microfluidic imaging chip could become a useful immobilization tool for quantitative fluorescence imaging of the body wall muscles in C. elegans.

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EFF-1 promotes muscle fusion, paralysis and retargets infection by AFF-1-coated viruses in C. elegans

10.1101/2020.05.17.099622 ◽

2020 ◽

Author(s):

Anna Meledin ◽

Xiaohui Li ◽

Elena Matveev ◽

Boaz Gildor ◽

Ofer Katzir ◽

...

Keyword(s):

Cell Fusion ◽

Body Wall ◽

Muscle Development ◽

Smooth Muscles ◽

Muscle Cells ◽

The Body ◽

Host Interactions ◽

C Elegans ◽

Body Wall Muscles ◽

Cell Cell

A hallmark of muscle development is that myoblasts fuse to form myofibers. However, smooth muscles and cardiomyocytes do not generally fuse. In C. elegans, the body wall muscles (BWMs), the physiological equivalents of skeletal muscles, are mononuclear. Here, to determine what would be the consequences of fusing BWMs, we express the cell-cell fusogen EFF-1 in these cells. We find that EFF-1 induces paralysis and dumpy phenotypes. To determine whether EFF-1-induced muscle fusion results in these pathologies we injected viruses pseudotyped with AFF-1, a paralog of EFF-1, into the pseudocoelom of C. elegans. When these engineered viruses encounter cells expressing EFF-1 or AFF-1 they are able to infect them as revealed by GFP expression from the viral genome. We find that AFF-1 viruses can fuse to EFF-1-expressing muscles revealing multinucleated fibers that cause paralysis and abnormal muscle morphogenesis. Thus, aberrant fusion of otherwise non-syncytial muscle cells may lead to pathological conditions.Graphical abstractSignificance statementMost cells are individual units that do not mix their cytoplasms. However, some cells fuse to become multinucleated in placenta, bones and muscles. In most animals, muscles are formed by myofibers that originate by cell-cell fusion. In contrast, in C. elegans the body wall muscles are mononucleated cells that mediate worm-like movement. EFF-1 and AFF-1 fusogens mediate physiological cell fusion in C. elegans. By ectopically expressing EFF-1 in body wall muscles we induce their fusion resulting in behavioral and morphological deleterious effects, revealing possible causes of congenital myopathies in humans. Using AFF-1-coated pseudoviruses we infect EFF-1-expressing muscle cells retargeting viral infection into these cells. We suggest that virus retargeting can be utilized to study myogenesis, neuronal regeneration, gamete fusion and screens for new fusogens in different organisms. In addition, our virus retargeting system can be used in gene-therapy, viral-based oncolysis and to study viral-host interactions.

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