This work was supported by grants from the Natural Sciences and Engineering Research Council (NSERC) of Canada and The Canada Foundation for Innovation. Thanks to Dr Paul Mains (University of Calgary, Calgary, Canada) for let-502(sb118ts) strain. Some of the strains were provided by the Caenorhabditis Genetics Center, which is funded by NIH Office of Research Infrastructure Programs (P40 OD010440).

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The authors declare that they have no competing financial interests.

Dieses Protokoll beschreibt neue Metriken frühen und späten Phasen der embryonalen Dehnung zu charakterisieren. Im Bereich 1 ist der kritische Schritt die mögliche Anwesenheit von Bakterien auf dem Pad. Die Embryonen werden hermetisch zwischen dem Kissen und dem Deckglas während der Bilderfassung eingeschlossen ist. die Folie Abdichtung ist erforderlich während der Erfassung Desikkation der Tiere zu vermeiden, dass mehr als zwei Stunden dauert. Unseres Wissens nach keiner der Versiegelu...

Seit fast 50 Jahren gründeten die Nematode Caenorhabditis elegans sich als leistungsfähiges Modell wichtige Fragen in der Entwicklung, der Neurobiologie, evolution, Wirt-Pathogen - Interaktionen usw. 1 Die Stärke dieses Modells in der Studie der Entwicklung zu studieren , liegt in: seiner kurzen Lebenszyklus von 3 Tagen; die Leichtigkeit, mit der diese Tiere gentechnisch verändert werden; seine Transparenz, die die Beobachtung der Zell Verschiebung und Morphologie in lebenden Tieren und deren Entwicklung, die vor allem Extrauterin- ist ermöglicht. Die Entwicklungsstadien des Nematoden umfassen Embryonalentwicklung und vier Larvenstadien (L1 bis L4), gefolgt von Erwachsenenalter. Während der embryonalen Entwicklung, zog epidermal Morphogenese beträchtliche Aufmerksamkeit auf seine Fähigkeit, um ein besseres Verständnis davon, wie Epithelzellen wandern als Gruppe zu ermöglichen, wie sie ihre junctions reorganisieren und ändern ihre individuellen Morphologie sowie deren relative Positionierung innerhalb eines funktionellen Epithels.Epidermal Morphogenese ist in vier Stufen unterteilt: dorsale Einlagerungs bestehend in der Reorganisation der dorsalen epidermalen Zellen, als der Unterhaut bezeichnet; ventralen Gehäuse, in der Migration von ventralen hypodermal Zellen in Richtung der ventralen Mittellinie aus so den Embryo in einer epithelialen Zellschicht umhüllt; Früh- und Spät Dehnung Umwandlung der bohnenförmigen Embryos in vermiform Larven. Im Anschluss an die Morphogenese, Embryo Luke und L1-Larven beginnen mit den verfügbaren Bakterien in ihrer unmittelbaren Umgebung ernähren. Embryonic Dehnung ist daher eine späte Phase der Embryonalentwicklung. Es besteht aus der Verlängerung des Embryos entlang seiner Längsachse und eine Verringerung seines Querdurchmesser. Dies bedeutet eine drastische Änderung der Form der hypodermalen Zellen. Dehnung ist unterteilt in eine frühe und eine späte Phase. Die frühe Phase beginnt mit dem Komma Bühne und endet , wenn die Körperwand Muskeln in w bei 1,75-facher Etappenvertragsild Typ (wt) Embryonen - entsprechend Embryonen , die 1,75-fache in der Länge im Vergleich zu nicht verlängert Embryonen. Morphogene Prozesse in diesem Stadium auftreten , werden in erster Linie durch die Kontraktion von fädigen Aktinbündel (FB) am apikalen Pol hypodermal Zellen angeordnet angetrieben, die ihre Dehnung entlang der anteroposterioren Achse des Embryos 2 fahren. Die Kontraktion der FBs ist die Kontrolle durch die Phosphorylierung von Myosin-Leichtketten durch drei Kinasen LET-502 / ROCK, MRCK-1 und PAK-1 5. Die Spätphase der Verlängerung beginnt, wenn die Körperwand Muskeln funktionsfähig werden und Contracting beginnen. Es geht um Mechanotransduktion Signalisierung von den Körperwandmuskulatur zu den dorsalen und ventralen hypodermal Zellen und endet , wenn die Tiere 3 schlüpfen. Dehnungsfehler werden durch den Prozentsatz der Tiere als Embryonen (Embryonale Letalität; Emb) sterben im Allgemeinen gekennzeichnet und diejenigen zu verhaften ihre Entwicklung als L1-Larven (Larven Verhaftung Phänotyp; Lva) aufweist und deutlich kürzer als Gew. Bezeichnung des Stadium der Entwicklungsstopp erfordert mikroskopische Beobachtung von toten Embryonen und verhaftet Larvae 3-6. Es wurde vor kurzem gezeigt , dass mehrere Gene, wie die Cdc42 / Rac Regler und Effektor pix-1 und pak-1, während morphogenic Prozesse steuern sowohl frühe als auch späte Dehnung 3,7. Wir zeigten auch vor kurzem , dass morphogenic Prozesse entlang der anteroposterioren Achse der Embryonen während der frühen Verlängerung 3 7 unterscheiden. Diese Erkenntnisse die Entwicklung neuer Metriken motiviert speziell frühe oder späte Verlängerung Stadien und anderen Metriken Targeting ermöglicht die Charakterisierung der Morphologie der Embryonen entlang ihrer anteroposterioren Achse während der frühen Dehnung. Diese neuen Verfahren bestehen, um die Länge von Embryonen zu Beginn und am Ende des frühen Dehnung sowie die Breite der bei der Messung erAnzeigen und Schwänzen. 7 Zwei Protokolle wurden auch die Länge der frisch geschlüpften Larven zu messen entwickelt, synchronisiert auf L1 Stufe 7. Die Eischalen der Embryonen schützen sie gegen alkalischen Hypochlorit-Behandlung während Larven, Erwachsene und Bakterien in den Kulturmedien durch die Behandlung gelöst sind. Diese Behandlung wird dann verwendet , Embryonen zu reinigen , aus einem nicht-synchronisierten Population eine Mehrheit von gut ernährt Erwachsene 8 enthält. Lebensmittel Einschränkung verwendet frisch geschlüpften Larven zu synchronisieren. Messen der Länge dieser Larven wird dann verwendet, Verlängerung Defekte zu detektieren. Diese Messung wird über die Messung der verhafteten Larven auf Kulturplatten bevorzugt, da Larven, die aus nicht vollständig länglichen Embryonen schlüpfen können &quot;normale Länge&quot; erholen, wenn Fütterung aber ihre reduzierte Größe beibehalten, wenn in Abwesenheit von Lebensmitteln festgenommen. Hier präsentieren wir detaillierte Protokolle ermöglichen die Messung der lenge von Embryonen sowie die Breite des Kopfes und der Schwanz mit Zeitraffer-DIC-Mikroskopie und Bildanalyse (Protokoll 1) verlängert wird. Wir bieten auch detaillierte Protokolle über die Länge der synchronisierten Larven mittels Bildanalyse (Protokoll 2) und Durchflusszytometrie (Protokoll 3) zu messen.

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			<td height="21" style="height:21px;width:216px;">glass slides</td>
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</table>

novel metrics to characterize embryonic elongation of the nematode caenorhabditis elegans

Dissecting the signaling pathways that control the alteration of morphogenic processes during embryonic development requires robust and sensitive metrics. Embryonic elongation of the nematode Caenorhabditis elegans is a late developmental stage consisting of the elongation of the embryo along its longitudinal axis. This developmental stage is controlled by intercellular communication between hypodermal cells and underlying body-wall muscles. These signaling mechanisms control the morphology of hypodermal cells by remodeling the cytoskeleton and the cell-cell junctions. Measurement of embryonic lethality and developmental arrest at larval stages as well as alteration of cytoskeleton and cell-cell adhesion structures in hypodermal and muscle cells are classical phenotypes that have been used for more than 25 years to dissect these signaling pathways. Recent studies required the development of novel metrics specifically targeting either early or late elongation and characterizing morphogenic defects along the antero-posterior axis of the embryo. Here, we provide detailed protocols enabling the accurate measurement of the length and the width of the elongating embryos as well as the length of synchronized larvae. These methods constitute useful tools to identify genes controlling elongation, to assess whether these genes control both early and late phases of this stage and are required evenly along the antero-posterior axis of the embryo.

Head-, Schwanz- und Kopf / Schwanz-Breite - Verhältnis sind Robust Metrics. Die Protokolle hier beschrieben wurden während der frühen Verlängerung 7. Pix-1 und pak-1 - Code jeweils für eine Guanin-Austauschfaktor Funktion der Regulatoren un...

Watch this Scientific Journal Video about Novel Metrics to Characterize Embryonic Elongation of the Nematode Caenorhabditis elegans at JoVE.com

Novel Metrics to Characterize Embryonic Elongation of the Nematode Caenorhabditis elegans

Novel Metrics zur Charakterisierung von Embryonic Dehnung des Nematode<em&gt; Caenorhabditis elegans</em

Here we detail protocols specifically designed to monitor morphogenic defects that occur during early and late phases of embryonic elongation of the nematode Caenorhabditis elegans. Ultimately, these protocols are designed to identify genes that regulate these phases and to characterize their differential requirements along the antero-posterior axis of the embryo.

Dissecting the signaling pathways that control the alteration of morphogenic processes during embryonic development requires robust and sensitive metrics. ...

novel-metrics-to-characterize-embryonic-elongation-nematode

Research

JoVE Journal

Neuroscience

Novel Metrics to Characterize Embryonic Elongation of the Nematode Caenorhabditis elegans

6.0K Aufrufe.  Université du Québec à Montréal. Here we detail protocols specifically designed to monitor morphogenic defects that occur during early and late phases of embryonic elongation of the nematode Caenorhabditis elegans. Ultimately, these protocols are designed to identify genes that regulate these phases and to characterize their differential requirements along the antero-posterior axis of the embryo. 

Serie: Novel Metrics to Characterize Embryonic Elongation of the Nematode Caenorhabditis elegans

Multi-unit Recording Methods to Characterize Neural Activity in the Locust (Schistocerca Americana) Olfactory Circuits

Detection and interpretation of olfactory cues are critical for the survival of many organisms. Remarkably, species across phyla have strikingly similar olfactory systems suggesting that the biological approach to chemical sensing has been optimized over evolutionary time1. In the insect olfactory system, odorants are transduced by olfactory receptor neurons (ORN) in the antenna, which convert chemical stimuli into trains of action potentials. Sensory input from the ORNs is then relayed to the antennal lobe (AL; a structure analogous to the vertebrate olfactory bulb). In the AL, neural representations for odors take the form of spatiotemporal firing patterns distributed across ensembles of principal neurons (PNs; also referred to as projection neurons)2,3. The AL output is subsequently processed by Kenyon cells (KCs) in the downstream mushroom body (MB), a structure associated with olfactory memory and learning4,5. Here, we present electrophysiological recording techniques to monitor odor-evoked neural responses in these olfactory circuits.
First, we present a single sensillum recording method to study odor-evoked responses at the level of populations of ORNs6,7. We discuss the use of saline filled sharpened glass pipettes as electrodes to extracellularly monitor ORN responses. Next, we present a method to extracellularly monitor PN responses using a commercial 16-channel electrode3. A similar approach using a custom-made 8-channel twisted wire tetrode is demonstrated for Kenyon cell recordings8. We provide details of our experimental setup and present representative recording traces for each of these techniques.

Multi-unit Recording Methods to Characterize Neural Activity in the Locust Schistocerca Americana Olfactory Circuits

We demonstrate variations of the extracellular multi-unit recording technique to characterize odor-evoked responses in the first three stages of the invertebrate olfactory pathway. These techniques can easily be adapted to examine ensemble activity in other neural systems as well.

Multi-unit Recording Methoden zur neuronalen Aktivität in der Locust Charakterisieren (<em&gt; Schistocerca Americana</em&gt;) Olfaktorische Circuits

Detection and interpretation of olfactory cues are critical for the survival  of many organisms. Remarkably, species across phyla have strikingly similar ...

Forschung

Neurowissenschaften

A Caenorhabditis elegans Model System for Amylopathy Study

Amylopathy is a term that describes abnormal synthesis and accumulation of amyloid beta (A&beta;) in tissues with time. A&beta; is a hallmark of Alzheimer's disease (AD) and is found in Lewy body dementia, inclusion body myositis and cerebral amyloid angiopathy 1-4. Amylopathies progressively develop with time. For this reason simple organisms with short lifespans may help to elucidate molecular aspects of these conditions. Here, we describe experimental protocols to study A&beta;-mediated neurodegeneration using the worm Caenorhabditis elegans. Thus, we construct transgenic worms by injecting DNA encoding human A&beta;42 into the syncytial gonads of adult hermaphrodites. Transformant lines are stabilized by a mutagenesis-induced integration. Nematodes are age synchronized by collecting and seeding their eggs. The function of neurons expressing A&beta;42 is tested in opportune behavioral assays (chemotaxis assays). Primary neuronal cultures obtained from embryos are used to complement behavioral data and to test the neuroprotective effects of anti-apoptotic compounds.

A Caenorhabditis elegans Model System for Amylopathy Study

We describe methods to study aspects of amylopathies in the worm C. elegans. We show how to construct worms expressing human A&beta;42 in neurons and how to test their function in behavioral assays. We further show how to obtain primary neuronal cultures that can be used for pharmacological testing.

A<em&gt; Caenorhabditis elegans</em&gt; Modell-System für Amylopathy Study

Amylopathy is a term that describes abnormal synthesis and accumulation of amyloid beta (A&beta;) in tissues with time. A&beta; is a hallmark of ...

Methods for Studying the Mechanisms of Action of Antipsychotic Drugs in Caenorhabditis elegans

Caenorhabditis elegans is a simple genetic organism amenable to large-scale forward and reverse genetic screens and chemical genetic screens. The C. elegans genome includes potential antipsychotic drug (APD) targets conserved in humans, including genes encoding proteins required for neurotransmitter synthesis and for synaptic structure and function. APD exposure produces developmental delay and/or lethality in nematodes in a concentration-dependent manner. These phenotypes are caused, in part, by APD-induced inhibition of pharyngeal pumping1,2. Thus, the developmental phenotype has a neuromuscular basis, making it useful for pharmacogenetic studies of neuroleptics. Here we demonstrate detailed procedures for testing APD effects on nematode development and pharyngeal pumping. For the developmental assay, synchronized embryos are placed on nematode growth medium (NGM) plates containing APDs, and the stages of developing animals are then scored daily. For the pharyngeal pumping rate assay, staged young adult animals are tested on NGM plates containing APDs. The number of pharyngeal pumps per unit time is recorded, and the pumping rate is calculated. These assays can be used for studying many other types of small molecules or even large molecules.

Methods for Studying the Mechanisms of Action of Antipsychotic Drugs in Caenorhabditis elegans

Approaches for testing the effects of antipsychotic drugs (APDs) in Caenorhabditis elegans are demonstrated. Assays are described for testing drug effects on development and viability and on pharyngeal pumping rate. These methods are also applicable for pharmacogenetic experiments with drug classes other than APDs.

Methoden zur Untersuchung der Wirkmechanismen von Psychopharmaka in<em&gt; Caenorhabditis elegans</em

Caenorhabditis elegans is a simple genetic organism amenable to  large-scale forward and reverse genetic screens and chemical genetic screens. The C.  ...

An Assay for Measuring the Effects of Ethanol on the Locomotion Speed of Caenorhabditis elegans

Alcohol use disorders are a significant public health concern, for which there are few effective treatment strategies. One difficulty that has delayed the development of more effective treatments is the relative lack of understanding of the molecular underpinnings of the effects of ethanol on behavior. The nematode, Caenorhabditis elegans (C.&#160;elegans), provides a useful model in which to generate and test hypotheses about the molecular effects of ethanol. Here, we describe an assay that has been developed and used to examine the roles of particular genes and environmental factors in behavioral responses to ethanol, in which locomotion is the behavioral output. Ethanol dose-dependently causes an acute depression of crawling on an agar surface. The effects are dynamic; animals exposed to a high concentration demonstrate an initial strong depression of crawling, referred to here as initial sensitivity, and then partially recover locomotion speed despite the continued presence of the drug. This ethanol-induced behavioral plasticity is referred to here as the development of acute functional tolerance. This assay has been used to demonstrate that these two phenotypes are distinct and genetically separable. The straightforward locomotion assay described here is suitable for examining the effects of both genetic and environmental manipulations on these acute behavioral responses to ethanol in C.&#160;elegans.

An Assay for Measuring the Effects of Ethanol on the Locomotion Speed of Caenorhabditis elegans

C. elegans is a useful model for studying the effects of ethanol on behavior. We present a behavioral assay that quantifies the effects of ethanol on the locomotion speed of crawling worms; both initial sensitivity and the development of acute functional tolerance to ethanol can be measured with this assay.

Ein Test zur Messung der Wirkung von Ethanol auf die Fortbewegungsgeschwindigkeit der<em&gt; Caenorhabditis elegans</em

Alcohol use disorders are a significant public health concern, for which there are few effective treatment strategies. One difficulty that has delayed the ...

Agarose Microchambers for Long-term Calcium Imaging of Caenorhabditis elegans

Behavior is controlled by the nervous system. Calcium imaging is a straightforward method in the transparent nematode Caenorhabditis elegans to measure the activity of neurons during various behaviors. To correlate neural activity with behavior, the animal should not be immobilized but should be able to move. Many behavioral changes occur during long time scales and require recording over many hours of behavior. This also makes it necessary to culture the worms in the presence of food. How can worms be cultured and their neural activity imaged over long time scales? Agarose Microchamber Imaging (AMI) was previously developed to culture and observe small larvae and has now been adapted to study all life stages from early L1 until the adult stage of C. elegans. AMI can be performed on various life stages of C. elegans. Long-term calcium imaging is achieved without immobilizing the animals by using short externally triggered exposures combined with an electron multiplying charge-coupled device (EMCCD) camera recording. Zooming out or scanning can scale up this method to image up to 40 worms in parallel. Thus, a method is described to image behavior and neural activity over long time scales in all life stages of C. elegans.

Agarose Microchambers for Long-term Calcium Imaging of Caenorhabditis elegans

Imaging behavior and neural activity over long time scales without immobilization of the animal is a prerequisite to understand behavior. Agarose microfluidic chambers imaging (AMI) can be used to image neural activity and behavior for all life stages of Caenorhabditis elegans.

Agarose Mikrokammern für Langzeit Calcium Imaging von<em&gt; Caenorhabditis elegans</em

Behavior is controlled by the nervous system. Calcium imaging is a straightforward method in the transparent nematode Caenorhabditis elegans to measure ...

Dynamic Quantitative Sensory Testing to Characterize Central Pain Processing

Central facilitation and modulation of incoming nociceptive signals play an important role in the perception of pain. Disruption in central pain processing is present in many chronic pain conditions and can influence responses to specific therapies. Thus, the ability to precisely describe the state of central pain processing has profound clinical significance in both prognosis and prediction. Because it is not practical to record neuronal firings directly in the human spinal cord, surrogate behavior tests become an important tool to assess the state of central pain processing. Dynamic QST is one such test, and can probe both the ascending facilitation and descending modulation of incoming nociceptive signals via TS and CPM, respectively. Due to the large between-individual variability in the sensitivity to noxious signals, standardized TS and CPM tests may not yield any meaningful data in up to 50% of the population due to floor or ceiling effects. We present methodologies to individualize TS and CPM so we can capture these measures in a broader range of individuals than previously possible. We have used these methods successfully in several studies at the lab, and data from one ongoing study will be presented to demonstrate feasibility and potential applications of the methods.

By assessing pain in response to repetitive or different types of standardized stimuli, dynamic quantitative sensory testing (QST) can reveal changes in the central processing of pain. We present methods to optimize and individualize two dynamic QST measures: temporal summation (TS) and conditioned pain modulation (CPM).

Dynamische Quantitative Sensory Testing zu Charakterisieren zentralen Schmerzverarbeitung

Central facilitation and modulation of incoming nociceptive signals play an important role in the perception of pain. Disruption in central pain ...

A Caenorhabditis elegans Nutritional-status Based Copper Aversion Assay

To ensure survival, organisms must be capable of avoiding unfavorable habitats while ensuring a consistent food source. Caenorhabditis elegans alter their locomotory patterns upon detection of diverse environmental stimuli and can modulate their suite of behavioral responses in response to starvation conditions. Nematodes typically exhibit a decreased aversive response when removed from a food source for over 30 min. Observation of behavioral changes in response to a changing nutritional status can provide insight into the mechanisms that regulate the transition from a well-fed to starved state.
We have developed an assay that measures a nematode&#39;s ability to cross an aversive barrier (i.e. copper) then reach a food source over a prolonged period of time. This protocol builds upon previous work by integrating multiple variables in a manner that allows for continued data collection as the organisms shift towards an increasingly starved condition. Moreover, this assay permits an increased sample size so that larger populations of nematodes can be simultaneously evaluated.
Organisms defective for the ability to detect or respond to copper immediately cross the chemical barrier, while wild type nematodes are initially repelled. As wild type worms are increasingly starved, they begin to cross the barrier and reach the food source. We designed this assay to evaluate a mutant that is incapable of responding to diverse environmental cues, including food sensation or detection of aversive chemicals. When evaluated via this protocol, the defective organisms immediately crossed the barrier, but were also incapable of detecting a food source. Hence, these mutants repeatedly cross the chemical barrier despite temporarily reaching a food source. This assay can straightforwardly test populations of worms to evaluate potential pathway defects related to aversion and starvation.

A Caenorhabditis elegans Nutritional-status Based Copper Aversion Assay

Here, we present a Caenorhabditis elegans-specific assay designed to evaluate changes in copper aversion behavior and the ability to locate a common food source, as the organism progresses from a well-fed to starved nutritional state.

EIN<em&gt; Caenorhabditis elegans</em&gt; Nährwert-basierter Kupfer-Aversion-Assay

To ensure survival, organisms must be capable of avoiding unfavorable habitats while ensuring a consistent food source. Caenorhabditis elegans alter their ...

Ratiometric Calcium Imaging of Individual Neurons in Behaving Caenorhabditis Elegans

It has become increasingly clear that neural circuit activity in behaving animals differs substantially from that seen in anesthetized or immobilized animals. Highly sensitive, genetically encoded fluorescent reporters of Ca2+ have revolutionized the recording of cell and synaptic activity using non-invasive optical approaches in behaving animals. When combined with genetic and optogenetic techniques, the molecular mechanisms that modulate cell and circuit activity during different behavior states can be identified.
Here we describe methods for ratiometric Ca2+ imaging of single neurons in freely behaving Caenorhabditis elegans worms. We demonstrate a simple mounting technique that gently overlays worms growing on a standard Nematode Growth Media (NGM) agar block with a glass coverslip, permitting animals to be recorded at high-resolution during unrestricted movement and behavior. With this technique, we use the sensitive Ca2+ reporter GCaMP5 to record changes in intracellular Ca2+ in the serotonergic Hermaphrodite Specific Neurons (HSNs) as they drive egg-laying behavior. By co-expressing mCherry, a Ca2+-insensitive fluorescent protein, we can track the position of the HSN within ~ 1 &#181;m and correct for fluctuations in fluorescence caused by changes in focus or movement. Simultaneous, infrared brightfield imaging allows for behavior recording and animal tracking using a motorized stage. By integrating these microscopic techniques and data streams, we can record Ca2+ activity in the C. elegans egg-laying circuit as it progresses between inactive and active behavior states over tens of minutes.

Ratiometric Calcium Imaging of Individual Neurons in Behaving Caenorhabditis Elegans

This protocol describes the use of genetically encoded Ca2+ reporters to record changes in neural activity in behaving Caenorhabditis elegans worms. &#8195;

Ratiometrischen Kalzium Imaging einzelner Neuronen im Verhalten Caenorhabditis Elegans

It has become increasingly clear that neural circuit activity in behaving animals differs substantially from that seen in anesthetized or immobilized ...

Imaging Dendritic Spines in Caenorhabditis elegans

Dendritic spines are specialized sites of synaptic innervation modulated by activity and serve as substrates for learning and memory. Recently, dendritic spines have been described for DD GABAergic neurons as the input sites from presynaptic cholinergic neurons in the motor circuit of Caenorhabditis elegans. This synaptic circuit can now serve as a powerful new in vivo model of spine morphogenesis and function that exploits the facile genetics and ready accessibility of C. elegans to live-cell imaging. 
This protocol describes experimental strategies for assessing DD spine structure and function. In this approach, a super-resolution imaging strategy is used to visualize the intricate shapes of actin-rich dendritic spines. To evaluate the DD spine function, the light-activated opsin, Chrimson, stimulates the presynaptic cholinergic neurons, and the calcium indicator, GCaMP, reports the evoked calcium transients in postsynaptic DD spines. Together, these methods comprise powerful approaches for identifying genetic determinants of dendritic spines in C. elegans that could also direct spine morphogenesis and function in the brain.

Imaging Dendritic Spines in Caenorhabditis elegans

Dendritic spines are important cellular features of the nervous system. Here live imaging methods are described for assessing the structure and function of dendritic spines in C. elegans.&#160;These approaches support the development of mutant screens for genes that define dendritic spine shape or function.

Bildgebung dendritischer Dornen bei Caenorhabditis elegans

Dendritic spines are specialized sites of synaptic innervation modulated by activity and serve as substrates for learning and memory. Recently, dendritic ...

In vivo Assessment of Microtubule Dynamics and Orientation in Caenorhabditis elegans Neurons

In neurons, microtubule orientation has been a key assessor to identify axons that have plus-end out microtubules and dendrites that generally have mixed orientation. Here we describe methods to label, image, and analyze the microtubule dynamics and growth during the development and regeneration of touch neurons in C. elegans. Using genetically encoded fluorescent reporters of microtubule tips, we imaged the axonal microtubules. The local changes in microtubule behavior that initiates axon regeneration following axotomy can be quantified using this protocol. This assay is adaptable to other neurons and genetic backgrounds to investigate the regulation of microtubule dynamics in various cellular processes.

In vivo Assessment of Microtubule Dynamics and Orientation in Caenorhabditis elegans Neurons

A protocol for imaging the dynamic microtubules in vivo using fluorescently labeled End binding protein has been presented. We described the methods to label, image, and analyze the dynamic microtubules in the Posterior lateral microtubule (PLM) neuron of C. elegans.

Im lebenden Organismus Beurteilung der Dynamik und Orientierung von Mikrotubuli in Caenorhabditis elegans Neuronen

In neurons, microtubule orientation has been a key assessor to identify axons that have plus-end out microtubules and dendrites that generally have mixed ...

Novel Metrics zur Charakterisierung von Embryonic Dehnung des Nematode

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Methoden zur Untersuchung der Wirkmechanismen von Psychopharmaka in

Ein Test zur Messung der Wirkung von Ethanol auf die Fortbewegungsgeschwindigkeit der

Agarose Mikrokammern für Langzeit Calcium Imaging von

Dynamische Quantitative Sensory Testing zu Charakterisieren zentralen Schmerzverarbeitung

EIN

Ratiometrischen Kalzium Imaging einzelner Neuronen im Verhalten Caenorhabditis Elegans

Bildgebung dendritischer Dornen bei Caenorhabditis elegans

Im lebenden Organismus Beurteilung der Dynamik und Orientierung von Mikrotubuli in Caenorhabditis elegans Neuronen