This work is supported by a grant from the National Natural Science Foundation of China (No.31472037). Any mention of trade names or commercial products in this article is solely for the purpose of providing specific information and does not imply a recommendation.

1. Preparation of Instruments and Insect
<ol>
	<li>Preparing tungsten electrodes and stimuli solutions
	<ol>
		<li>Fix a new tungsten wire (diameter of 0.125 mm, length of 75 mm) into a micromanipulator and sharpen it in a 10% (w/v) sodium nitrite (NaNO2) solution in a syringe at 10 V provided by a power supply for about 1 min under a stereomicroscope (40X magnification).</li>
		<li>Dip the sharpened tungsten wire repeatedly into the 10% NaNO2 solution, about 4 mm at 5 V in &#60; 1 min (Figure 1A).</li>
		<li>Examine the diameter of the sharpened tungsten tip frequently under the stereomicroscope until it is fine enough to penetrate the cuticle of a locust palp olfactory sensillum (Figure 1B).</li>
		<li>Prepare the stimulus solutions. Dilute each of the chemical stimulus substance in mineral oil. Dilute 1-nonanol and nonanoic acid at 10% dilutions. Dilute E-2-hexenal and hexanal at 10-2, 10-3, 10-4, and 10-5.</li>
		<li>Prepare Pasteur tubes carrying the stimuli: insert filter paper strips (length of 2 cm, width of 0.5 cm) into the Pasteur tubes, add the diluted stimulus solutions (each 10 &#181;l) to the filter paper strips, and then plug the Pasteur tubes with pipette tips (1 ml).</li>
	</ol>
	</li>
	<li>Prepare the insect
	<ol>
		<li>Rear locusts (Locusta migratoria) with fresh wheat seedlings under crowded conditions at a relative humidity of 60%, a temperature of 28 - 30 &#176;C, and a photoperiod of 18:6 h (light:dark). Choose 1- to 3-day-old 5th instar locust nymphs and remove the antennae with fine scissors to avoid any interference when recording.</li>
	</ol>
	</li>
	<li>Preparing the locust maxillary palp holder
	<ol>
		<li>Use a glass slide (25 mm x 75 mm) as the base of the maxillary palp holder (MPH). Attach a plastic piece (1 mm in height, 10 mm in width, 35 mm in length) to a corner of the glass slide with double-sided adhesive tape, and finally fix a cover glass (18 mm x 18 mm) on top of the plastic piece with double-sided adhesive tape. Place a small piece of red rubber tape onto the cover glass as a non-slip layer. The plastic piece and the cover glass constitute the platform for the locust palp. The height of the platform is approximately 1.5 mm.</li>
		<li>Install a tungsten wire (diameter of 0.125 mm, length of 36 mm) at a distance of 1.5 mm parallel to the inside edge of the platform. Fix the two ends of the wire onto the platform with double-sided adhesive tape.</li>
	</ol>
	</li>
</ol>
2. Preparation of Locust Maxillary Palps
<ol>
	<li>Cut a centrifuge tube (1.5 ml) vertically in half and cut off the bottom. Place the locust into the prepared tube. Leave the ventral region and the head of the locust exposed. Fix the assembly to the glass slide with double-sided adhesive tape (Figure 2A).</li>
	<li>Pull the right maxillary palp onto the platform.</li>
	<li>Put the tungsten wire at the fourth segment of the palp. Place adhesive putty on each side of the tungsten wire, about 2 mm from the maxillary palp (Figure 2A and 2B).</li>
</ol>
3. Single Sensillum Recordings
<ol>
	<li>Place the locust maxillary palp preparation under a microscope at a low magnification (100X). Adjust the position of the preparation until the palp is perpendicular to the recording electrode (Figure 3A).</li>
	<li>Insert the reference electrode (tungsten electrode) into the locust eye using a micromanipulator. Move the recording electrode (tungsten electrode) close to the maxillary palp with the micromanipulator (Figure 3B and 3C).</li>
	<li>Adjust the odor delivery device to about 1 cm from the maxillary palp (Figure 3B).</li>
	<li>Open the recording software Auto Spike 32. Set the recording parameters as follows: the recording scale on 500 &#181;V; the high cutoff of the filter on 300 Hz, the low cutoff on 200 Hz; and the pretrigger on 10 s.</li>
	<li>Connect the recording electrode to a 10x universal AC/DC amplifier.</li>
	<li>Switch the microscope to a high magnification (500X). Insert the recording electrode into the base of a basiconic sensillum on the maxillary palp and delicately adjust the recording electrode to obtain good spontaneous spikes (Figure 3D).</li>
	<li>Open the stimulus controller to deliver a continuous air stream at 20 ml/s. Set the stimulation time to 1 s. Record signals for 10 s, starting 10 s before the onset of the stimulus pulse.</li>
	<li>Use a 10x universal AC/DC amplifier to amplify the signals. Feed the signals into the IDAC 4. Analyze the signals with the Auto Spike 32 software. AC signals are band-pass filtered between 200 to 300 Hz. Use Auto Spike 32 to distinguish peak-to-trough amplitudes from noises. Calculate the responses of the neurons as the increases in action potential frequencies (spikes per second) over the spontaneous frequencies. Perform a statistical analysis using GraphPad Prism 7.</li>
</ol>

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The authors have nothing to disclose.

Insects rely on palps to detect food odors, and their palps are believed to play an important role in speciation13,27. The palps are simple olfactory organs and are receiving increasing attention as an attractive model for the exploration of the neuromolecular networks underlying chemosensation28.
Insect labellar and palp SSRs have been successfully performed on Drosophila melanogaster, Anopheles ga...

Animals have evolved a range of chemosensory organs that sense exogenous chemical cues. In insects, the most important chemosensory organs are the antennae and the palps. On these organs, several types of chemosensory hairs, called chemosensory sensilla, are innervated by chemosensory neurons (CSNs) within the hairs. CSNs in chemosensory sensilla recognize specific chemical cues through signal transduction from chemical stimuli to electrical potentials that are subsequently transferred up to the central nervous systems1,2,3.
CSNs express various chemosensory receptors [e.g., odorant receptors (ORs)], ionotropic receptors (IRs), and gustatory receptors (GRs) on their membranes, which encode exogenous chemical cues associated with different types of chemosensation4,5,6. The characterization of CSNs is key to the elucidation of cellular and molecular mechanisms of insect chemoreception. Now single sensillum recording (SSR) is a widely-used technique for the characterization of insect CSNs in the antennal sensilla of many insects, including flies7, moths8, beetles9, aphids10, locusts11, and ants12. However, few studies have applied an SSR to insect palps13,14,15,16,17, because the particular structures of their sensilla make an electrophysiological recording difficult18.
Swarms of locusts (Orthoptera) often cause serious crop damage and economic loss19. The palps are believed to play an important role in the food selection of locusts20,21,22,23,24. Two types of chemosensory sensilla are investigated by a scanning electron microscope (SEM). Usually, 350 sensilla chaetica and 7 - 8 sensilla basiconica are observed on each dome of the locust palps18. Sensilla chaetica are gustatory sensilla that sense non-volatile chemical cues, whereas sensilla basiconica have an olfactory function, sensing volatile chemical cues.
On locust palps, the diameters of the hair sockets of the sensilla basiconica (ca. 12 &#181;m), are much greater than those of sensilla chaetica (ca. 8 &#181;m)18,25. The cuticular wall of the sensilla basiconica on the palps is much thicker than that of antennal sensilla18. In addition, the dome of the palp has fluid contents within a highly flexible cuticle. These characteristics mean that a penetration with a microelectrode and an acquisition of good electrophysiological signals is more difficult than for antennal sensilla. In this paper, a detailed and highly effective SSR protocol for locust palp sensilla basiconica is presented with a video.

<table><tbody><tr><td>Tungsten wire</td><td>ADVENT</td><td>W559504</td><td>Used for making the electrode and fixing the palp</td></tr><tr><td>NaNO&lt;sub&gt;2&lt;/sub&gt;</td><td>Sigma-aldrich</td><td>563218-25G</td><td>Used for sharpening the tungsten wire</td></tr><tr><td>AC Power Supply</td><td>Syntech</td><td>A2-70</td><td>Providing the voltage in sharpening the tungsten wire</td></tr><tr><td>Stereoscope</td><td>Motic</td><td>SMZ-163</td><td>Used for observing the sharpening of tungsten wire</td></tr><tr><td>Microscope</td><td>Olympus</td><td>W-51</td><td>Used for observing the sensilla on locust maxillary palp</td></tr><tr><td>Intelligent Data Acquisition Controller</td><td>Syntech</td><td>IDAC-4</td><td>Real-time on screen display of all signals before and during recording</td></tr><tr><td>Stimulus controller</td><td>Syntech</td><td>CS-55</td><td>Used for controlling the stimulus application</td></tr><tr><td>Electronic micromanipulator</td><td>C.M.D.T</td><td>CFT-8301D</td><td>Used for minor movement of the recording electrode</td></tr><tr><td>Micromanipulator</td><td>Narishige</td><td>MN-151</td><td>Used for minor movement of the reference electrode</td></tr><tr><td>Speaker</td><td>EDIFIER</td><td>R101T06</td><td>Connected with IDAC-4 and providing sound for the signal</td></tr><tr><td>Magnetic base</td><td>PDOK</td><td>PD-101</td><td>Used to hold the electrode, and stimulus delivery tube</td></tr><tr><td>Vibration Isolation Table</td><td>TianHe</td><td>HAP-100-1208</td><td>Used for isolating the vibration from the equipment</td></tr><tr><td>Glass slide</td><td>CITOGLAS</td><td>ZBP-407</td><td>Used for making the base for the MPH</td></tr><tr><td>Blu-tack</td><td>Bostik</td><td>Blu-tack-45g</td><td>Fixing the tungsten wire</td></tr><tr><td>Pasteur tube</td><td>YARE</td><td>WITEG</td><td>Placing the filter paper containing stimuli stimulus solutions</td></tr></tbody></table>

single sensillum recordings for locust palp sensilla basiconica

The palps of locust mouthparts are considered to be conventional gustatory organs that play an important role in a locust&#39;s food selection, especially for the detection of non-volatile chemical cues through sensilla chaetica (previously named terminal sensilla or crested sensilla). There is now increasing evidence that these palps also have an olfactory function. An odorant receptor (LmigOR2) and an odorant-binding protein (LmigOBP1) have been localized in the neurons and accessory cells, respectively, in the sensilla basiconica of the palps. Single sensillum recording (SSR) is used for recording the responses of odorant receptor neurons, which is an effective method for screening active ligands on specific odorant receptors. SSR is used in functional studies of odorant receptors in palp sensilla. The structure of the sensilla basiconica located on the dome of the palps differs somewhat from the structure of those on the antennae. Therefore, when performing an SSR elicited by odorants, some specific advice may be helpful for obtaining optimum results. In this paper, a detailed and highly effective protocol for an SSR from insect palp sensilla basiconica is introduced.

Two sensilla subtypes (pb1 and pb2) on the locust maxillary palp are identified based on different response dynamics to chemical odorants (10% 1-nonanol and 10% nonanoic acid). The neurons in pb1 produce significantly more spikes to 1-nonanol than to nonanoic acid while the neurons in pb2 are significantly less activated by 1-nonanol compared with nonanoic acid (Figure 4). Hexanal and E-2-Hexenal can evoke a locust palp opening response (POR)<sup class="xref"...

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Single Sensillum Recordings for Locust Palp Sensilla Basiconica

This paper describes a detailed and highly effective protocol for single sensillum recordings from the sensilla basiconica on the palps of insect mouthparts.

The palps of locust mouthparts are considered to be conventional gustatory organs that play an important role in a locust&#39;s food selection, especially ...

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8.1K Views.  China Agricultural University. This paper describes a detailed and highly effective protocol for single sensillum recordings from the sensilla basiconica on the palps of insect mouthparts.

Video: Single Sensillum Recordings for Locust Palp Sensilla Basiconica

Single Sensillum Recordings in the Insects Drosophila melanogaster and Anopheles gambiae

The sense of smell is essential for insects to find foods, mates, predators, and oviposition sites3. Insect olfactory sensory neurons (OSNs) are enclosed in sensory hairs called sensilla, which cover the surface of olfactory organs. The surface of each sensillum is covered with tiny pores, through which odorants pass and dissolve in a fluid called sensillum lymph, which bathes the sensory dendrites of the OSNs housed in a given sensillum. The OSN dendrites express odorant receptor (OR) proteins, which in insects function as odor-gated ion channels4, 5. The interaction of odorants with ORs either increases or decreases the basal firing rate of the OSN. This neuronal activity in the form of action potentials embodies the first representation of the quality, intensity, and temporal characteristics of the odorant6, 7.
Given the easy access to these sensory hairs, it is possible to perform extracellular recordings from single OSNs by introducing a recording electrode into the sensillum lymph, while the reference electrode is placed in the lymph of the eye or body of the insect. In Drosophila, sensilla house between one and four OSNs, but each OSN typically displays a characteristic spike amplitude. Spike sorting techniques make it possible to assign spiking responses to individual OSNs. This single sensillum recording (SSR) technique monitors the difference in potential between the sensillum lymph and the reference electrode as electrical spikes that are generated by the receptor activity on OSNs1, 2, 8. Changes in the number of spikes in response to the odorant represent the cellular basis of odor coding in insects. Here, we describe the preparation method currently used in our lab to perform SSR on Drosophila melanogaster and Anopheles gambiae, and show representative traces induced by the odorants in a sensillum-specific manner.

Single Sensillum Recordings in the Insects Drosophila melanogaster and Anopheles gambiae

Electrophysiological responses of olfactory sensory neurons to odorants can be measured in insects using single sensillum recordings. In this video article we will demonstrate how to perform single sensillum recordings in the antennae of the vinegar fly (Drosophila melanogaster) and the maxillary palps of the malaria mosquito (Anopheles gambiae).

The sense of smell is essential for insects to find foods, mates, predators, and oviposition sites3. Insect olfactory sensory neurons (OSNs) are enclosed ...

Electrophysiological Measurements from a Moth Olfactory System

Insect olfactory systems provide unique opportunities for recording odorant-induced responses in the forms of electroantennograms (EAG) and single sensillum recordings (SSR), which are summed responses from all odorant receptor neurons (ORNs) located on the antenna and from those housed in individual sensilla, respectively. These approaches have been exploited for getting a better understanding of insect chemical communication. The identified stimuli can then be used as either attractants or repellents in management strategies for insect pests.

Insect olfactory systems provide unique opportunities for recording odorant-induced responses in the forms of electroantennograms (EAG) and single sensillum recordings (SSR), which are summed responses from all odorant receptor neurons (ORNs) located on the antenna and from those housed in individual sensilla, respectively.

Insect olfactory systems provide unique opportunities for recording odorant-induced responses in the forms of electroantennograms (EAG) and single ...

Electrophysiology of Scorpion Peg Sensilla

We describe a modification of an existing tip-recording technique1,2 for electrophysiologically investigating short, peg-like sensory sensilla3,4. On the mid-ventral surface of all scorpions are two appendages called pectines, which have dense fields of mechano- and chemosensory peg sensilla5,6. One method for assessing chemoresponsiveness of these sensilla uses a tungsten electrode for extracellularly recording neural activity within a sensillum as a volatile odorant is introduced to the sensory field5,7. The limitations of this method include slow data collection and uncontrolled stimulant introduction to, and removal from, the peg field. To overcome these limitations, we developed a new tip-recording technique that uses nonpolar mineral oil as a medium through which to deliver water-based tastants to individual peg sensilla8,9. We have successfully applied this method to obtain sensillar chemoresponses to citric acid, ethanol, and salt. Here we describe the experimental protocol for such a study9. We think this new method may be useful for studying the response properties of other arthropod chemosensory systems, including those of insects10, 11 and crustaceans12.

This article describes an electrophysiological method for isolating chemical stimulation to individual sensilla via extracellular, tip-recordings under mineral oil.

We describe a modification of an existing tip-recording technique1,2 for electrophysiologically investigating short, peg-like sensory sensilla3,4. On the ...

Sample Preparation Method of Scanning and Transmission Electron Microscope for the Appendages of Woodboring Beetle

This report described sample preparation methods that scanning and transmission electron microscope observations, demonstrated by preparing appendages of the woodboring beetle, Chlorophorus caragana Xie &#38; Wang (2012), for both types of electron microscopy. The scanning electron microscopy (SEM) sample preparation protocol was based on sample chemical fixation, dehydration in a series of ethanol baths, drying, and sputter-coating. By adding Tween 20 (Polyoxyethylene sorbitan laurate) to the fixative and the wash solution, the insect body surface of woodboring beetle was washed more cleanly in SEM. This study&#39;s transmission electron microscopy (TEM) sample preparation involved a series of steps including fixation, ethanol dehydration, embedding in resin, positioning using fluorescence microscopy, sectioning, and staining. Fixative with Tween 20 enabled penetrate the insect body wall of woodboring beetle more easily than it would had been without Tween 20, and subsequently better fixed tissues and organs in the body, thus yielded clear transmission electron microscope observations of insect sensilla ultrastructures. The next step of this preparation was determining the positions of insect sensilla in the sample embedded in the resin block by using fluorescence microscopy to increase the precision of target sensilla positioning. This improved slicing accuracy.

In order to observe ultrastructure of insect sensilla, scanning and transmission electron microscopy (SEM and TEM, respectively) sample preparation protocol were presented in the study. Tween 20 was added into the fixative to avoid sample deformation in SEM. Fluorescence microscopy was helpful for improving slicing accuracy in TEM.

This report described sample preparation methods that scanning and transmission electron microscope observations, demonstrated by preparing appendages of ...

Environment

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.

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

Electrophysiological Recording From Drosophila Labellar Taste Sensilla

The peripheral taste response of insects can be powerfully investigated with electrophysiological techniques. The method described here allows the researcher to measure gustatory responses directly and quantitatively, reflecting the sensory input that the insect nervous system receives from taste stimuli in its environment. This protocol outlines all key steps in performing this technique. The critical steps in assembling an electrophysiology rig, such as selection of necessary equipment and a suitable environment for recording, are delineated. We also describe how to prepare for recording by making appropriate reference and recording electrodes, and tastant solutions. We describe in detail the method used for preparing the insect by insertion of a glass reference electrode into the fly in order to immobilize the proboscis. We show traces of the electrical impulses fired by taste neurons in response to a sugar and a bitter compound. Aspects of the protocol are technically challenging and we include an extensive description of some common technical challenges that may be encountered, such as lack of signal or excessive noise in the system, and potential solutions. The technique has limitations, such as the inability to deliver temporally complex stimuli, observe background firing immediately prior to stimulus delivery, or use water-insoluble taste compounds conveniently. Despite these limitations, this technique (including minor variations referenced in the protocol) is a standard, broadly accepted procedure for recording Drosophila neuronal responses to taste compounds.

Electrophysiological Recording From Drosophila Labellar Taste Sensilla

This protocol describes extracellular recording of the action potential responses fired by labellar taste neurons in Drosophila.

The peripheral taste response of insects can be powerfully investigated with electrophysiological techniques. The method described here allows the ...

Using Single Sensillum Recording to Detect Olfactory Neuron Responses of Bed Bugs to Semiochemicals

The insect olfactory system plays an important role in detecting semiochemicals in the environment. In particular, the antennal sensilla which house single or multiple neurons inside, are considered to make the major contribution in responding to the chemical stimuli. By directly recording action potential in the olfactory sensillum after exposure to stimuli, single sensillum recording (SSR) technique provides a powerful approach for investigating the neural responses of insects to chemical stimuli. For the bed bug, which is a notorious human parasite, multiple types of olfactory sensillum have been characterized. In this study, we demonstrated neural responses of bed bug olfactory sensilla to two chemical stimuli and the dose-dependent responses to one of them using the SSR method. This approach enables researchers to conduct early screening for individual chemical stimuli on the bed bug olfactory sensilla, which would provide valuable information for the development of new bed bug attractants or repellents and benefits the bed bug control efforts.

Bed bugs rely on olfactory receptor neurons housed in their antennal olfactory sensilla to detect semiochemicals in the environment. Utilizing single sensillum recording, we demonstrate a method to evaluate bed bug response to semiochemicals and explore the coding process involved.

The insect olfactory system plays an important role in detecting semiochemicals in the environment. In particular, the antennal sensilla which house ...

Localization of Odorant Receptor Genes in Locust Antennae by RNA In Situ Hybridization

Insects have evolved sophisticated olfactory reception systems to sense exogenous chemical signals. These chemical signals are transduced by Olfactory Receptor Neurons (ORNs) housed in hair-like structures, called chemosensilla, of the antennae. On the ORNs&#39; membranes, Odorant Receptors (ORs) are believed to be involved in odor coding. Thus, being able to identify genes localized to the ORNs is necessary to recognize OR genes, and provides a fundamental basis for further functional in situ studies. The RNA expression levels of specific ORs in insect antennae are very low, and preserving insect tissue for histology is challenging. Thus, it is difficult to localize an OR to a specific type of sensilla using RNA in situ hybridization. In this paper, a detailed and highly effective RNA in situ hybridization protocol particularly for lowly expressed OR genes of insects, is introduced. In addition, a specific OR gene was identified by conducting double-color fluorescent in situ hybridization experiments using a co-expressing receptor gene, Orco, as a marker.

Localization of Odorant Receptor Genes in Locust Antennae by RNA In Situ Hybridization

This paper describes a detailed and highly effective RNA in situ hybridization protocol particularly for low-level expressed Odorant Receptor (OR) genes, as well as other genes, in insect antennae using digoxigenin (DIG)-labeled or biotin-labeled probes.

Insects have evolved sophisticated olfactory reception systems to sense exogenous chemical signals. These chemical signals are transduced by Olfactory ...

Electrophysiological Recording from Drosophila Trichoid Sensilla in Response to Odorants of Low Volatility

Insects rely on their sense of smell to guide a wide range of behaviors that are critical for their survival, such as food-seeking, predator avoidance, oviposition, and mating. Myriad chemicals of varying volatilities have been identified as natural odorants that activate insect Olfactory Receptor Neurons (ORNs). However, studying the olfactory responses to low-volatility odorants has been hampered by an inability to effectively present such stimuli using conventional odor-delivery methods. Here, we describe a procedure that permits the effective presentation of low-volatility odorants for in vivo Single-Sensillum Recording (SSR). By minimizing the distance between the odor source and the target tissue, this method allows for the application of biologically salient but hitherto inaccessible odorants, including palmitoleic acid, a stimulatory pheromone with a demonstrated effect on ORNs involved in courtship and mating behavior1. Our procedure thus affords a new avenue to assay a host of low-volatility odorants for the study of insect olfaction and pheromone communication.

Electrophysiological Recording from Drosophila Trichoid Sensilla in Response to Odorants of Low Volatility

The overall goal of this protocol is to demonstrate how to present odorants of low volatility for single-sensillum recording from Drosophila olfactory receptor neurons that respond to long-chain cuticular pheromones.

Insects rely on their sense of smell to guide a wide range of behaviors that are critical for their survival, such as food-seeking, predator avoidance, ...

A Novel Method for Enhanced Analysis of Insect Taste Neuron Activity

Base Recording: A Technique for Analyzing Responses of Taste Neurons in Drosophila

Insects taste the external world through taste hairs, or sensilla, that have pores at their tips. When a sensillum comes into contact with a potential food source, compounds from the food source enter through the pore and activate neurons within. For over 50 years, these responses have been recorded using a technique called tip recording. However, this method has major limitations, including the inability to measure neural activity before or after stimulus contact and the requirement for tastants to be soluble in aqueous solutions. We describe here a technique that we call base recording, which overcomes these limitations. Base recording allows the measurement of taste neuron activity before, during, and after the stimulus. Thus, it allows extensive analysis of OFF responses that occur after a taste stimulus. It can be used to study hydrophobic compounds such as long-chain pheromones that have very low solubility in water. In summary, base recording offers the advantages of single-sensillum electrophysiology as a means of measuring neuronal activity - high spatial and temporal resolution, without the need for genetic tools - and overcomes key limitations of the traditional tip recording technique.

Author Spotlight: Advances in Chemoreception &#8211; From Insect Odor Receptors to Non-Coding RNAs

A rarely used method of electrophysiological recording, base recording, allows analysis of features of taste coding that cannot be examined by conventional recording methods. Base recording also allows the analysis of taste responses to hydrophobic stimuli that cannot be studied using traditional electrophysiological methods.

Insects taste the external world through taste hairs, or sensilla, that have pores at their tips. When a sensillum comes into contact with a potential ...

Single Sensillum Recordings for Locust Palp Sensilla Basiconica

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Chapters in this video

Single Sensillum Recordings in the Insects Drosophila melanogaster and Anopheles gambiae

Electrophysiological Measurements from a Moth Olfactory System

Electrophysiology of Scorpion Peg Sensilla

Sample Preparation Method of Scanning and Transmission Electron Microscope for the Appendages of Woodboring Beetle

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

Electrophysiological Recording From Drosophila Labellar Taste Sensilla

Using Single Sensillum Recording to Detect Olfactory Neuron Responses of Bed Bugs to Semiochemicals

Localization of Odorant Receptor Genes in Locust Antennae by RNA In Situ Hybridization

Electrophysiological Recording from Drosophila Trichoid Sensilla in Response to Odorants of Low Volatility

Base Recording: A Technique for Analyzing Responses of Taste Neurons in Drosophila