Simultaneous recording of behavioral and neural responses of free-moving nematodes C. elegans

AbstractSleep, a state of quiescence associated with growth and restorative processes, is conserved across species. Invertebrates including the nematode Caenorhabditis elegans exhibit sleep-like states during development and periods of satiety and stress. Here we describe two methods to study behavior and associated neural activity during sleep and awake states in adult C. elegans. A large microfluidic device facilitates population-wide assessment of long-term sleep behavior over 12 h, including effects of fluid flow, oxygen, feeding, odors, and genetic perturbations. Smaller devices allow simultaneous recording of sleep behavior and neuronal activity, and a closed-loop sleep detection system delivers chemical stimuli to individual animals to assess sleep-dependent changes to neural responses. Sleep increased the arousal threshold to aversive chemical stimulation, yet sensory neuron (ASH) and first-layer interneuron (AIB) responses were unchanged. This localizes adult sleep-dependent neuromodulation within interneurons presynaptic to the AVA premotor interneurons, rather than afferent sensory circuits.

Download Full-text

Area-specific thalamocortical synchronization underlies the transition from motor planning to execution

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2012658118 ◽

2021 ◽

Vol 118 (6) ◽

pp. e2012658118

Author(s):

Abdulraheem Nashef ◽

Rea Mitelman ◽

Ran Harel ◽

Mati Joshua ◽

Yifat Prut

Keyword(s):

Primary Motor Cortex ◽

Premotor Cortex ◽

Cell Activity ◽

Motor Planning ◽

Simultaneous Recording ◽

Delayed Response ◽

Neural Responses ◽

Cortical Cells ◽

Reaching Task ◽

Motor Thalamus

We studied correlated firing between motor thalamic and cortical cells in monkeys performing a delayed-response reaching task. Simultaneous recording of thalamocortical activity revealed that around movement onset, thalamic cells were positively correlated with cell activity in the primary motor cortex but negatively correlated with the activity of the premotor cortex. The differences in the correlation contrasted with the average neural responses, which were similar in all three areas. Neuronal correlations reveal functional cooperation and opposition between the motor thalamus and distinct motor cortical areas with specific roles in planning vs. performing movements. Thus, by enhancing and suppressing motor and premotor firing, the motor thalamus can facilitate the transition from a motor plan to execution.

Download Full-text

Tissue mechanics and somatosensory neural responses govern touch sensation inC. elegans

10.1101/471904 ◽

2018 ◽

Cited By ~ 1

Author(s):

A. Sanzeni ◽

S. Katta ◽

B.C. Petzold ◽

B.L. Pruitt ◽

M.B. Goodman ◽

...

Keyword(s):

Model Organism ◽

Quantitative Model ◽

Tissue Mechanics ◽

The Body ◽

Elastic Model ◽

Prime Model ◽

Neural Responses ◽

C Elegans ◽

Somatosensory Neurons ◽

Broad Variety

The sense of touch hinges on tissues transducing stimuli applied to the skin and somatosensory neurons converting mechanical inputs into currents. Like mammalian Pacinian corpuscles, the light-touch response of the prime model organismC. elegansadapts rapidly, and is symmetrically activated by the onset and offset of a step indentation. Here, we propose a quantitative model that combines transduction of stimuli across the skin and subsequent gating of mechanoelectrical channels. For mechanics, we use an elastic model based on geometrically-nonlinear deformations of a pressurized cylindrical shell. For gating, we build upon consequences of the dermal layer’s thinness and tangential stimuli. Our model demonstrates how the onset-offset symmetry arises from the coupling of mechanics and adaptation, and accounts for experimental neural responses to a broad variety of stimuli. Predicted effects of modifications in the mechanics or the internal pressure of the body are tested against mechanical and neurophysiological experiments.

Download Full-text

Corollary Discharge Promotes a Sustained Motor State in a Neural Circuit for Navigation

10.1101/861559 ◽

2019 ◽

Cited By ~ 1

Author(s):

Ni Ji ◽

Vivek Venkatachalam ◽

Hillary Rodgers ◽

Wesley Hung ◽

Taizo Kawano ◽

...

Keyword(s):

Neural Circuit ◽

Genetic Manipulation ◽

Feedback Mechanism ◽

Corollary Discharge ◽

Neural Responses ◽

State Representation ◽

Motor Representation ◽

State Information ◽

C Elegans ◽

Positive Feedback Mechanism

AbstractAnimals exhibit behavioral and neural responses that persist on longer time scales than transient or fluctuating stimulus inputs. Here, we report that C. elegans uses corollary discharge to sustain motor responses during thermotactic navigation. By imaging circuit activity in behaving animals, we show that a principal postsynaptic partner of the AFD thermosensory neuron, the AIY interneuron, encodes both temperature and motor state information. By optogenetic and genetic manipulation of this circuit, we demonstrate that the motor state representation in AIY is a corollary discharge signal. RIM, an interneuron that is connected with premotor interneurons, is required for corollary discharge. Ablation of RIM eliminates the motor representation in AIY, allows thermosensory representations to reach downstream premotor interneurons, and reduces the animal’s ability to sustain forward movements during thermotaxis. We propose that corollary discharge underlies a positive feedback mechanism to generate persistent neural activity and sustained behavioral patterns in a sensorimotor transformation.

Download Full-text

Corollary discharge promotes a sustained motor state in a neural circuit for navigation

eLife ◽

10.7554/elife.68848 ◽

2021 ◽

Vol 10 ◽

Author(s):

Ni D Ji ◽

Vivek Venkatachalam ◽

Hillary Denise Rodgers ◽

Wesley Hung ◽

Taizo Kawano ◽

...

Keyword(s):

Sensory Processing ◽

Neural Circuit ◽

Genetic Manipulation ◽

Feedback Mechanism ◽

Corollary Discharge ◽

Neural Responses ◽

Motor Representation ◽

Motor Circuit ◽

C Elegans ◽

Positive Feedback Mechanism

Animals exhibit behavioral and neural responses that persist on longer time scales than transient or fluctuating stimulus inputs. Here, we report that C. elegans uses feedback from the motor circuit to a sensory processing interneuron to sustain its motor state during thermotactic navigation. By imaging circuit activity in behaving animals, we show that a principal postsynaptic partner of the AFD thermosensory neuron, the AIY interneuron, encodes both temperature and motor state information. By optogenetic and genetic manipulation of this circuit, we demonstrate that the motor state representation in AIY is a corollary discharge signal. RIM, an interneuron that is connected with premotor interneurons, is required for this corollary discharge. Ablation of RIM eliminates the motor representation in AIY, allows thermosensory representations to reach downstream premotor interneurons, and reduces the animal's ability to sustain forward movements during thermotaxis. We propose that feedback from the motor circuit to the sensory processing circuit underlies a positive feedback mechanism to generate persistent neural activity and sustained behavioral patterns in a sensorimotor transformation.

Download Full-text

The glycomes of Caenorhabditis elegans and other model organisms

Biochemical Society Symposium ◽

10.1042/bss0690117 ◽

2002 ◽

Vol 69 ◽

pp. 117-134 ◽

Cited By ~ 47

Author(s):

Stuart M. Haslam ◽

David Gems ◽

Howard R. Morris ◽

Anne Dell

Keyword(s):

Caenorhabditis Elegans ◽

Current Knowledge ◽

Structural Data ◽

Model Organisms ◽

Entire Genome ◽

C Elegans ◽

The Face ◽

Area Of Concern ◽

Nematode Worm

There is no doubt that the immense amount of information that is being generated by the initial sequencing and secondary interrogation of various genomes will change the face of glycobiological research. However, a major area of concern is that detailed structural knowledge of the ultimate products of genes that are identified as being involved in glycoconjugate biosynthesis is still limited. This is illustrated clearly by the nematode worm Caenorhabditis elegans, which was the first multicellular organism to have its entire genome sequenced. To date, only limited structural data on the glycosylated molecules of this organism have been reported. Our laboratory is addressing this problem by performing detailed MS structural characterization of the N-linked glycans of C. elegans; high-mannose structures dominate, with only minor amounts of complex-type structures. Novel, highly fucosylated truncated structures are also present which are difucosylated on the proximal N-acetylglucosamine of the chitobiose core as well as containing unusual Fucα1–2Gal1–2Man as peripheral structures. The implications of these results in terms of the identification of ligands for genomically predicted lectins and potential glycosyltransferases are discussed in this chapter. Current knowledge on the glycomes of other model organisms such as Dictyostelium discoideum, Saccharomyces cerevisiae and Drosophila melanogaster is also discussed briefly.

Download Full-text

How do histone modifications contribute to transgenerational epigenetic inheritance in C. elegans?

Biochemical Society Transactions ◽

10.1042/bst20190944 ◽

2020 ◽

Vol 48 (3) ◽

pp. 1019-1034 ◽

Cited By ~ 1

Author(s):

Rachel M. Woodhouse ◽

Alyson Ashe

Keyword(s):

Histone Modifications ◽

Molecular Mechanisms ◽

Epigenetic Inheritance ◽

Nematode Caenorhabditis Elegans ◽

Histone Methyltransferases ◽

Transgenerational Epigenetic Inheritance ◽

C Elegans ◽

Recent Developments ◽

Gene Regulatory

Gene regulatory information can be inherited between generations in a phenomenon termed transgenerational epigenetic inheritance (TEI). While examples of TEI in many animals accumulate, the nematode Caenorhabditis elegans has proven particularly useful in investigating the underlying molecular mechanisms of this phenomenon. In C. elegans and other animals, the modification of histone proteins has emerged as a potential carrier and effector of transgenerational epigenetic information. In this review, we explore the contribution of histone modifications to TEI in C. elegans. We describe the role of repressive histone marks, histone methyltransferases, and associated chromatin factors in heritable gene silencing, and discuss recent developments and unanswered questions in how these factors integrate with other known TEI mechanisms. We also review the transgenerational effects of the manipulation of histone modifications on germline health and longevity.

Download Full-text

Centrosome Aurora A gradient ensures single polarity axis in C. elegans embryos

Biochemical Society Transactions ◽

10.1042/bst20200298 ◽

2020 ◽

Vol 48 (3) ◽

pp. 1243-1253 ◽

Cited By ~ 1

Author(s):

Sukriti Kapoor ◽

Sachin Kotak

Keyword(s):

Symmetry Breaking ◽

Cell Fate ◽

Cell Cortex ◽

Axis Formation ◽

Aurora A Kinase ◽

Aurora A ◽

C Elegans ◽

Cell Embryo ◽

Polarity Establishment

Cellular asymmetries are vital for generating cell fate diversity during development and in stem cells. In the newly fertilized Caenorhabditis elegans embryo, centrosomes are responsible for polarity establishment, i.e. anterior–posterior body axis formation. The signal for polarity originates from the centrosomes and is transmitted to the cell cortex, where it disassembles the actomyosin network. This event leads to symmetry breaking and the establishment of distinct domains of evolutionarily conserved PAR proteins. However, the identity of an essential component that localizes to the centrosomes and promotes symmetry breaking was unknown. Recent work has uncovered that the loss of Aurora A kinase (AIR-1 in C. elegans and hereafter referred to as Aurora A) in the one-cell embryo disrupts stereotypical actomyosin-based cortical flows that occur at the time of polarity establishment. This misregulation of actomyosin flow dynamics results in the occurrence of two polarity axes. Notably, the role of Aurora A in ensuring a single polarity axis is independent of its well-established function in centrosome maturation. The mechanism by which Aurora A directs symmetry breaking is likely through direct regulation of Rho-dependent contractility. In this mini-review, we will discuss the unconventional role of Aurora A kinase in polarity establishment in C. elegans embryos and propose a refined model of centrosome-dependent symmetry breaking.

Download Full-text

Simultaneous recording of pseudoaffective reflexes and motor activity in the jejunum of the anesthetized rat

Gastroenterology ◽

10.1016/s0016-5085(01)83569-1 ◽

2001 ◽

Vol 120 (5) ◽

pp. A717-A717

Author(s):

A TIMARPEREGRIN ◽

K KUMANO ◽

Z KHALIL ◽

G SANGER ◽

S BEECHAM ◽

...

Keyword(s):

Motor Activity ◽

Simultaneous Recording

Download Full-text

Olfactory Modulation of Steady- State Visual Evoked Potential Topography in Comparison with Differences in Odor Sensitivity

Journal of Psychophysiology ◽

10.1027//0269-8803.16.2.71 ◽

2002 ◽

Vol 16 (2) ◽

pp. 71-81 ◽

Cited By ~ 2

Author(s):

Caroline M. Owen ◽

John Patterson ◽

Richard B. Silberstein

Keyword(s):

Steady State ◽

Visual Evoked Potential ◽

Evoked Potential ◽

Behavioral Responses ◽

Simultaneous Recording ◽

Odor Concentration ◽

Odor Detection ◽

Detection Response ◽

Response Groups ◽

Visual Evoked

Summary Research was undertaken to determine whether olfactory stimulation can alter steady-state visual evoked potential (SSVEP) topography. Odor-air and air-only stimuli were used to determine whether the SSVEP would be altered when odor was present. Comparisons were also made of the topographic activation associated with air and odor stimulation, with the view toward determining whether the revealed topographic activity would differentiate levels of olfactory sensitivity by clearly identifying supra- and subthreshold odor responses. Using a continuous respiration olfactometer (CRO) to precisely deliver an odor or air stimulus synchronously with the natural respiration, air or odor (n-butanol) was randomly delivered into the inspiratory airstream during the simultaneous recording of SSVEPs and subjective behavioral responses. Subjects were placed in groups based on subjective odor detection response: “yes” and “no” detection groups. In comparison to air, SSVEP topography revealed cortical changes in response to odor stimulation for both response groups, with topographic changes evident for those unable to perceive the odor, showing the presence of a subconscious physiological odor detection response. Differences in regional SSVEP topography were shown for those who reported smelling the odor compared with those who remained unaware of the odor. These changes revealed olfactory modulation of SSVEP topography related to odor awareness and sensitivity and therefore odor concentration relative to thresholds.

Download Full-text