Este trabalho foi financiado por uma bolsa Dean Stanford (SEJdV), dos Institutos Nacionais de Saúde Prêmio Diretor Pioneer (TRC DP0035350), um Prêmio Fundação McKnight estudioso (TRC) e R01 EY022638 (TRC).

1. Gerar Moscas channelrodopsina <ol><li> Cruz UAS-chr2 moscas com o motorista Gal4 de sua escolha, nós usamos G105-Gal4, que é expressa em foma-1 neurônios no lóbulo óptico. </li><li> Para eliminar a possibilidade de uma resposta visual para o estímulo de luz azul, ambas as linhas de mosca são em aw fundo norpA +. </li><li> Resultado final: w + norpA; G105-Gal4/UAS-ChR2 + </li><li> Depois de moscas adultas eclose, colocar as fêmeas seleccionadas com alimento fresco, suplementado com 10 uM todo-trans-retinal (um co-factor necessário para a CHR2) e protegida da luz, durante 3 dias antes da realização do ensaio do comportamento. </li></ol> 2. Faça 10 Comida All-trans-retinal mM aprimorada <ol><li> Dissolver 100 mg de ácido todo-trans-retinal em 17,6 ml de etanol a 95% para tornar a 20 mM na retina. Manter todo-trans-retinal ao abrigo da luz em todos os momentos. </li><li> Derreta alimentos mosca padrão fubá no microondas, e deixe esfriar até que fique quente ao toque. </li><li> Misturar 50 ul de 20 mMall-trans-retinal em frascos de 10 ml de comida mosca. </li><li> Deixe arrefecer os frascos e manter ao abrigo da luz. </li></ol> 3. Equipamento <ol><li> Pontas de pipeta: Standard 1.000 pontas de pipeta uL são cortados perto da ponta, criando um diâmetro de poro de ~ 2,25 mm. </li><li> Da plataforma (ver figura 1). <ol><li> Uma base de Delrin, 17 cm x 25 cm, foi construído com orifícios roscados em cada canto para encaixar ¼ &quot;NPT conectores de mangueira de arrefecimento. </li><li> Um suporte vertical, feito de Delrin, está ligado ao centro da base. As dimensões totais são de 25 mm x 40 mm x 65 mm (largura x profundidade x altura). A ranhura 10 mm de largura corre o comprimento do suporte, com um parafuso de polegar na parte inferior. A plataforma está ligada à parte superior do suporte, 25 mm X 40 mm X 10 mm, com um furo de 3,5 mm de diâmetro alinhado com a ranhura no suporte. </li></ol></li><li> Matrizes de LED (ver Figura 1). <ol><li> Quatro braços de Refrigeração, ~ 18 cm de comprimento, estão afixadas na plataforma base utilizando o conector da mangueira de líquido refrigerante. Refrigeração é usado apenas como um suporte estrutural e não é utilizado para fins de refrigeração. </li><li> Ranhuras espaçadas adequadamente são cortadas na parte final do refrigerante mangueira de cada braço para fixar um dissipador de calor para a extremidade de cada braço. </li><li> A Rebel LED azul Tri-Stars é montada a cada dissipador de calor através de pré-corte de fita adesiva térmica. A CARCLO 18 ° Tri-lente é afixada em cada Tri Star. </li><li> LED Tri-Stars são ligados aos motoristas BuckPuck DC e uma fonte de alimentação, conforme especificado. Nós conseguimos o nosso set-up com cada BuckPuck ligar duas Tri-Stars em série. </li><li> Iluminação de todos os quatro LED Tri-estrelas a 700 mA rendeu uma irradiação de 713 W / m 2 na nossa plataforma. </li></ol></li><li> Câmara: A câmara está montada num tripé pequeno e centrou-se na parte superior da plataforma. </li></ol> 4. Ensaio Comportamental <ol><li> Resumidamente anestesiar moscas em gelo. </li><li> Coloque moscas individuais em pontas de pipeta, usando a fita para fecharambas as extremidades da ponta. </li><li> Após as moscas têm despertado e estão activamente a explorar a ponta da pipeta, retirar a fita adesiva e coloque uma pipeta na ranhura no suporte vertical. O parafuso de aperto manual é usado para proteger a ponta da pipeta no lugar e para fechar a parte inferior da ponta. </li><li> Como a mosca explora a ponta da pipeta (tipicamente 30 - 60 seg), iniciar a gravação da câmara imediatamente antes da mosca emerge da ponta para cima da plataforma. </li><li> Após a mosca surgiu na plataforma, espere 1-2 seco, e ligar os LEDs azul. Use um cronômetro para medir manualmente o tempo até que a mosca inicia vôo. </li></ol>

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<html> Nós demonstramos estimulação optogenética de comportamentos de fuga, banhando livremente caminhar moscas em luz azul brilhante. Esta abordagem pode ser facilmente adaptada para analisar outros comportamentos em moscas livremente a pé, e pode ser escalado para plataformas maiores, simplesmente ladrilhos as matrizes de LED que usamos em uma área maior. Usando uma câmera barata do que descrever, ou outros sistemas de câmera disponíveis, o usuário pode ajustar a taxa de quadros e resolução espacial das ima...

A crescente arsenal de ferramentas geneticamente codificados têm sido desenvolvidos para manipular actividade neural em células específicas na Drosophila melanogaster 1. Estas ferramentas permitem a ativação não-invasiva ou silenciamento de neurônios específicos no animal intacto, e se movimentar livremente. Entre estes, Channelrhodopsin2 (CHR2), um canal de catião activado pela luz, apresenta vantagens importantes, uma vez que pode ser temporalmente controlado e rapidamente induzido. Quando os neurônios que expressam chr2 estão expostos a brilhante luz azul (470 nm), eles rapidamente despolarizar e apresentam elevadas taxas de disparo 3-5. Ativação de neurônios como alvo específicos em animais livremente móveis revelou a suficiência de neurônios específicos para comportamentos como evitar CO 2 3, tromba extensão 2,4, ea gigante de fibra respostas de alarme mediadas 4. No entanto, como as fontes de luz intensa necessárias para estimular CHR2 também estimular fotorreceptores, aplicando optogenetic técnicas para o sistema visual tem sido limitada. Através da combinação de uma abordagem optogenética com uma mutação que prejudica a fototransdução, nós demonstramos que a activação de um conjunto específico de neurónios no lóbulo óptico da mosca pode conduzir a um comportamento de escape utilizado para evitar a colisão 6. A maioria, se não todos, os animais visuais exibem um comportamento de fuga para evitar colisões com objectos que se aproximam. Andar a pé ou parado moscas, quando se apresenta com uma colisão iminente, o arranque em vôo, longe da colisão iminente 7-9. Estes decolagens caracterizam-se por asas levantadas antes da descolagem e uma trajetória de vôo instável 10,11. Esta resposta é distinto do gigante fibra resposta mediada sobressalto, saltos que não são precedidos por asas levantados, e, normalmente, resultaria em uma queda em queda livre 4,9. Tendo identificado um cluster específico de neurônios sensíveis tear no lobo óptico, Foma-1 neurônios, que são uniquely atento para codificar objetos que se aproximam, procurou-se investigar o seu envolvimento na mosca comportamento de fuga tear. Aqui demonstramos o uso de optogenética para ativar seletivamente esses neurônios e provocar o comportamento da mosca fuga. Usamos o Gal4-UAS sistema activador transcricional de dirigir a expressão de CHR2-nos uma foma neurónios. Chr2 requer o co-fator todo-trans-retinal e como esta é encontrada em níveis baixos no sistema central nervoso Drosophila deve ser completado na dieta das moscas. 3,4 Como a luz brilhante é usado para ativar chr2 e moscas exibem comportamentos phototactic fortes 12, procurou-se eliminar a possibilidade de uma resposta visual ao estímulo. Para fazer isto, utilizou-se animais que eram mutantes homozigóticos para um alelo nulo do gene norpA, que codifica um componente crítico da cascata de fototransdução, fosfolipase C-β. Fotorreceptores em tais moscas mutantes são incapazes de responsabilidaded a luz 13. Para testar a estimulação optogenética da resposta de fuga, é necessário isolar uma única mosca e banhar em luz azul brilhante. Para fazer isso, nós colocamos moscas individuais em pontas de pipeta. Uma ponta de pipeta é colocada num suporte personalizado, de tal modo que a mosca vai geotactically subida da ponta e para fora para uma plataforma rectangular. A mosca é capaz de caminhar livremente em cima desta plataforma. A plataforma está rodeada por quatro matrizes de LED azul, cada um contendo três LEDs, voltadas para o topo da plataforma. Depois da passagem está na plataforma, os LEDs são iluminados, e resposta da mosca é gravado usando uma câmera de alta velocidade 6.

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optogenetic stimulation of escape behavior in drosophila melanogaster

Um número crescente de ferramentas codificados geneticamente estão ficando disponíveis que permitem não invasivo manipulação da actividade neural de neurónios específicos em Drosophila melanogaster 1. A principal delas são ferramentas optogenética, que permitem a ativação ou silenciamento de neurônios específicos no animal intacto, e movendo-se livremente com luz brilhante. Channelrodopsina (CHR2) é um canal de catião activado pela luz, que, quando activada pela luz azul, provoca a despolarização dos neurónios que expressam. Chr2 tem sido eficaz para a identificação de neurônios críticos para comportamentos específicos, tais como o CO 2 evasão, extensão e tromba gigante de fibra resposta de sobressalto mediada 2-4. No entanto, como as fontes de luz intensa, utilizados para estimular a CHR2 também estimular fotorreceptores, estas técnicas optogenética não tenham sido previamente utilizados no sistema visual. Aqui, nós combinamos uma abordagem optogenética com uma mutação que prejudica fototransdução a demonstrate que a ativação de um cluster de tear neurônios sensíveis em lobo óptico da mosca, foma-1 neurônios, pode dirigir um comportamento de fuga usado para evitar a colisão. Utilizou-se um alelo nulo de um componente crítico da cascata de fototransdução, fosfolipase C-β, codificada pelo gene norpA, para tornar a voa cego e também utilizar o Gal4-UAS sistema activador transcricional para comandar a expressão de CHR2 no Foma-1 neurônios. Moscas individuais são colocados em uma pequena plataforma cercada por LEDs azuis. Quando os LEDs são iluminadas, as moscas rapidamente descolagem em voo, de um modo semelhante ao comportamento visual impulsionada tear-escape. Nós acreditamos que esta técnica pode ser facilmente adaptada para analisar outros comportamentos em se movimentar livremente moscas.

Cego voa manifestou o chr2 ou o driver G105 só mostram uma baixa taxa de decolagem após a sua iluminação com luz azul brilhante. Cego moscas apresentaram a mesma taxa de descolagem independentemente de iluminação (Figura 2), sugerindo que estes eram take-off espontânea e não devido à iluminação com luz azul. Quando o CHR2 é expressa nos neurónios Foma1, no entanto, a iluminação com luz azul elicia a resposta de fuga. Mais de 50% das moscas testados tirou dentro de 1 segundo de iluminaçã...

Watch this Scientific Journal Video about Optogenetic Stimulation of Escape Behavior in Drosophila melanogaster at JoVE.com

Optogenetic Stimulation of Escape Behavior in Drosophila melanogaster

Ferramentas optogenética codificados geneticamente permitir a manipulação não invasiva de neurónios específicos no<em&gt; Drosophila</em&gt; Cérebro. Tais ferramentas podem identificar neurónios cuja activação é suficiente para induzir ou suprimir determinados comportamentos. Aqui apresentamos um método para ativar Channelrhodopsin2 que se expressa em neurônios específicos em moscas livremente a pé.

Optogenética estimulação do comportamento de fuga em<em&gt; Drosophila melanogaster</em

A  growing number of genetically encoded tools are becoming available that allow non-invasive  manipulation of the neural activity of specific neurons in ...

optogenetic-stimulation-of-escape-behavior-in-drosophila-melanogaster

Research

JoVE Journal

Neuroscience

Optogenetic Stimulation of Escape Behavior in Drosophila melanogaster

17.3K visualizações.  Stanford University. Ferramentas optogenética codificados geneticamente permitir a manipulação não invasiva de neurónios específicos no Drosophila Cérebro. Tais ferramentas podem identificar neurónios cuja activação é suficiente para induzir ou suprimir determinados comportamentos. Aqui apresentamos um método para ativar Channelrhodopsin2 que se expressa em neurônios específicos em moscas livremente a pé.

Vídeo: Optogenetic Stimulation of Escape Behavior in Drosophila melanogaster

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).

Único Recordings Sensillum na Insetos Drosophila melanogaster E Anopheles gambiae</em

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

Neurociência

Simultaneous Recording of Calcium Signals from Identified Neurons and Feeding Behavior of Drosophila melanogaster

To study neuronal networks in terms of their function in behavior, we must analyze how neurons operate when each behavioral pattern is generated. Thus, simultaneous recordings of neuronal activity and behavior are essential to correlate brain activity to behavior. For such behavioral analyses, the fruit fly, Drosophila melanogaster, allows us to incorporate genetically encoded calcium indicators such as GCaMP1, to monitor neuronal activity, and to use sophisticated genetic manipulations for optogenetic or thermogenetic techniques to specifically activate identified neurons2-5. Use of a thermogenetic technique has led us to find critical neurons for feeding behavior (Flood et al., under revision). As a main part of feeding behavior, a Drosophila adult extends its proboscis for feeding6 (proboscis extension response; PER), responding to a sweet stimulus from sensory cells on its proboscis or tarsi. Combining the protocol for PER7 with a calcium imaging technique8 using GCaMP3.01, 9, I have established an experimental system, where we can monitor activity of neurons in the feeding center &#x2013; the suboesophageal ganglion (SOG), simultaneously with behavioral observation of the proboscis. I have designed an apparatus ("Fly brain Live Imaging and Electrophysiology Stage": "FLIES") to accommodate a Drosophila adult, allowing its proboscis to freely move while its brain is exposed to the bath for Ca2+ imaging through a water immersion lens. The FLIES is also appropriate for many types of live experiments on fly brains such as electrophysiological recording or time lapse imaging of synaptic morphology. Because the results from live imaging can be directly correlated with the simultaneous PER behavior, this methodology can provide an excellent experimental system to study information processing of neuronal networks, and how this cellular activity is coupled to plastic processes and memory.

Simultaneous Recording of Calcium Signals from Identified Neurons and Feeding Behavior of Drosophila melanogaster

The fruit fly, Drosophila melanogaster, extends its proboscis for feeding, responding to a sugar stimulus from its proboscis or tarsus. I have combined observations of the proboscis extension response (PER) with a calcium imaging technique, allowing us to monitor the activity of neurons in the brain, simultaneously with behavioral observation.

De gravação simultânea de sinais de cálcio dos neurônios identificados e comportamento alimentar de Drosophila melanogaster</em

To study neuronal networks in terms of their function in behavior, we must analyze how neurons operate when each behavioral pattern is generated.  Thus, ...

Determination of the Spontaneous Locomotor Activity in Drosophila melanogaster

Drosophila melanogaster has been used as an excellent model organism to study environmental and genetic manipulations that affect behavior. One such behavior is spontaneous locomotor activity. Here we describe our protocol that utilizes Drosophila population monitors and a tracking system that allows continuous monitoring of the spontaneous locomotor activity of flies for several days at a time. This method is simple, reliable, and objective and can be used to examine the effects of aging, sex, changes in caloric content of food, addition of drugs, or genetic manipulations that mimic human diseases.

Determination of the Spontaneous Locomotor Activity in Drosophila melanogaster

Drosophila melanogaster are useful in studying genetic or environmental manipulations that affect behaviors such as spontaneous locomotor activity.&#160; Here we describe a protocol that utilizes monitors with infrared beams and data analysis software to quantify spontaneous locomotor activity.&#160;

Determinação da atividade locomotora espontânea em<em&gt; Drosophila melanogaster</em

Drosophila melanogaster has been used as an excellent model organism to study environmental and genetic manipulations that affect behavior. One such ...

In vivo Optogenetic Stimulation of the Rodent Central Nervous System

The ability to probe defined neural circuits in awake, freely-moving animals with cell-type specificity, spatial precision, and high temporal resolution has been a long sought tool for neuroscientists in the systems-level search for the neural circuitry governing complex behavioral states. Optogenetics is a cutting-edge tool that is revolutionizing the field of neuroscience and represents one of the first systematic approaches to enable causal testing regarding the relation between neural signaling events and behavior. By combining optical and genetic approaches, neural signaling can be bi-directionally controlled through expression of light-sensitive ion channels (opsins) in mammalian cells. The current protocol describes delivery of specific wavelengths of light to opsin-expressing cells in deep brain structures of awake, freely-moving rodents for neural circuit modulation. Theoretical principles of light transmission as an experimental consideration are discussed in the context of performing in vivo optogenetic stimulation. The protocol details the design and construction of both simple and complex laser configurations and describes tethering strategies to permit simultaneous stimulation of multiple animals for high-throughput behavioral testing.

In vivo Optogenetic Stimulation of the Rodent Central Nervous System

Optogenetics has become a powerful tool for use in behavioral neuroscience experiments. This protocol offers a step-by-step guide to the design and set-up of laser systems, and provides a full protocol for carrying out multiple and simultaneous in vivo optogenetic stimulations compatible with most rodent behavioral testing paradigms.

In vivo Optogenetic estimulação do sistema nervoso central de roedores

The ability to probe defined neural circuits in awake, freely-moving animals with cell-type specificity, spatial precision, and high temporal resolution ...

Optogenetic Stimulation of the Auditory Nerve

Direct electrical stimulation of spiral ganglion neurons (SGNs) by cochlear implants (CIs) enables open speech comprehension in the majority of implanted deaf subjects1-6. Nonetheless, sound coding with current CIs has poor frequency and intensity resolution due to broad current spread from each electrode contact activating a large number of SGNs along the tonotopic axis of the cochlea7-9. Optical stimulation is proposed as an alternative to electrical stimulation that promises spatially more confined activation of SGNs and, hence, higher frequency resolution of coding. In recent years, direct infrared illumination of&#160;the cochlea has been used to evoke responses in the auditory nerve10. Nevertheless it requires higher energies than electrical stimulation10,11 and uncertainty remains as to the underlying mechanism12. Here we describe a method based on optogenetics to stimulate SGNs with low intensity blue light, using transgenic mice with neuronal expression of channelrhodopsin 2 (ChR2)13 or virus-mediated expression of the ChR2-variant CatCh14. We used micro-light emitting diodes (&#181;LEDs) and fiber-coupled lasers to stimulate ChR2-expressing SGNs through a small artificial opening (cochleostomy) or the round window. We assayed the responses by scalp recordings of light-evoked potentials (optogenetic auditory brainstem response: oABR) or by microelectrode recordings from the auditory pathway and compared them with acoustic and electrical stimulation.

Cochlear implants (CIs) enable hearing by direct electrical stimulation of the auditory nerve. However, poor frequency and intensity resolution limits the quality of hearing with CIs. Here we describe optogenetic stimulation of the auditory nerve in mice as an alternative strategy for auditory research and developing future CIs.

A estimulação optogenética do nervo auditivo

Direct electrical stimulation of spiral ganglion neurons (SGNs) by cochlear implants (CIs) enables open speech comprehension in the majority of implanted ...

Conditions Affecting Social Space in Drosophila melanogaster

The social space assay described here can be used to quantify social interactions of Drosophila melanogaster &#8212; or other small insects &#8212; in a straightforward manner. As we previously demonstrated 1, in a two-dimensional chamber, we first force the flies to form a tight group, subsequently allowing them to take their preferred distance from each other. After the flies have settled, we measure the distance to the closest neighbor (or social space), processing a static picture with free online software (ImageJ). The analysis of the distance to the closest neighbor allows researchers to determine the effects of genetic and environmental factors on social interaction, while controlling for potential confounding factors. Diverse factors such as climbing ability, time of day, sex, and number of flies, can modify social spacing of flies. We thus propose a series of experimental controls to mitigate these confounding effects. This assay can be used for at least two purposes. First, researchers can determine how their favorite environmental shift (such as isolation, temperature, stress or toxins) will impact social spacing 1,2. Second, researchers can dissect the genetic and neural underpinnings of this basic form of social behavior 1,3. Specifically, we used it as a diagnostic tool to study the role of orthologous genes thought to be involved in social behavior in other organisms, such as candidate genes for autism in humans 4.

Conditions Affecting Social Space in Drosophila melanogaster

The effect of genes and environment on social space of Drosophila melanogaster can be quantified through a powerful but straightforward analytical paradigm. We show here different factors that can affect this social space, and thus need to be taken into consideration when designing experiments in this paradigm.

Condições que afetam Espaço Social em<em&gt; Drosophila melanogaster</em

The social space assay described here can be used to quantify social interactions of Drosophila melanogaster &#8212; or other small insects &#8212; in a ...

High-resolution Quantification of Odor-guided Behavior in Drosophila melanogaster Using the Flywalk Paradigm

In their natural environment, insects such as the vinegar fly Drosophila melanogaster are bombarded with a huge amount of chemically distinct odorants. To complicate matters even further, the odors detected by the insect nervous system usually are not single compounds but mixtures whose composition and concentration ratios vary. This leads to an almost infinite amount of different olfactory stimuli which have to be evaluated by the nervous system.
To understand which aspects of an odor stimulus determine its evaluation by the fly, it is therefore desirable to efficiently examine odor-guided behavior towards many odorants and odor mixtures. To directly correlate behavior to neuronal activity, behavior should be quantified in a comparable time frame and under identical stimulus conditions as in neurophysiological experiments. However, many currently used olfactory bioassays in Drosophila neuroethology are rather specialized either towards efficiency or towards resolution.
Flywalk, an automated odor delivery and tracking system, bridges the gap between efficiency and resolution. It allows the determination of exactly when an odor packet stimulated a freely walking fly, and to determine the animal&#180;s dynamic behavioral reaction.

High-resolution Quantification of Odor-guided Behavior in Drosophila melanogaster Using the Flywalk Paradigm

The automated tracking system Flywalk is used for high-resolution quantification of odor-guided behavior in Drosophila melanogaster.

De alta resolução Quantificação do Comportamento Odor-guiada em<em&gt; Drosophila melanogaster</em&gt; Usando a<em&gt; Flywalk</em&gt; Paradigm

In their natural environment, insects such as the vinegar fly Drosophila melanogaster are bombarded with a huge amount of chemically distinct odorants. To ...

A Simple Way to Measure Alterations in Reward-seeking Behavior Using Drosophila melanogaster

We describe a protocol for measuring ethanol self-administration in fruit flies (Drosophila melanogaster) as a proxy for changes in reward states. We demonstrate a simple way to tap into the fly reward system, modify experiences related to natural reward, and use voluntary ethanol consumption as a measure for changes in reward states. The approach serves as a relevant tool to study the neurons and genes that play a role in experience-mediated changes of internal state. The protocol is composed of two discrete parts: exposing the flies to rewarding and nonrewarding experiences, and assaying voluntary ethanol consumption as a measure of the motivation to obtain a drug reward. The two parts can be used independently to induce the modulation of experience as an initial step for further downstream assays or as an independent two-choice feeding assay, respectively. The protocol does not require a complicated setup and can therefore be applied in any laboratory with basic fly culture tools.

A Simple Way to Measure Alterations in Reward-seeking Behavior Using Drosophila melanogaster

We describe a protocol for inducing rewarding and nonrewarding experiences in fruit flies (Drosophila melanogaster) using voluntary ethanol consumption as a measure for changes in reward states.

Uma maneira simples para medir alterações na Recompensa comportamento de busca Usando<em&gt; Drosophila melanogaster</em

We describe a protocol for measuring ethanol self-administration in fruit flies (Drosophila melanogaster) as a proxy for changes in reward states. We ...

Quantification of Drosophila Grooming Behavior

Drosophila grooming behavior is a complex multi-step locomotor program that requires coordinated movement of both forelegs and hindlegs. Here we present a grooming assay protocol and novel chamber design that is cost-efficient and scalable for either small or large-scale studies of Drosophila grooming. Flies are dusted all over their body with Brilliant Yellow dye and given time to remove the dye from their bodies within the chamber. Flies are then deposited in a set volume of ethanol to solubilize the dye. The relative spectral absorbance of dye-ethanol samples for groomed versus ungroomed animals are measured and recorded. The protocol yields quantitative data of dye accumulation for individual flies, which can be easily averaged and compared across samples. This allows experimental designs to easily evaluate grooming ability for mutant animal studies or circuit manipulations. This efficient procedure is both versatile and scalable. We show work-flow of the protocol and comparative data between WT animals and mutant animals for the Drosophila type I Dopamine Receptor (DopR).

This protocol describes a scalable individual grooming assay technique in Drosophila that yields robust, quantitative data to measure grooming behavior. The method is based on comparing the difference in dye accumulation on the bodies of un-groomed versus groomed animals over a set period of time.

Quantificação do comportamento de higienização da Drosophila

Drosophila grooming behavior is a complex multi-step locomotor program that requires coordinated movement of both forelegs and hindlegs. Here we present a ...

Optogenetic Entrainment of Hippocampal Theta Oscillations in Behaving Mice

Extensive data on relationships of neural network oscillations to behavior and organization of neuronal discharge across brain regions call for new tools to selectively manipulate brain rhythms. Here we describe an approach combining projection-specific optogenetics with extracellular electrophysiology for high-fidelity control of hippocampal theta oscillations (5-10 Hz) in behaving mice. The specificity of the optogenetic entrainment is achieved by targeting channelrhodopsin-2 (ChR2) to the GABAergic population of medial septal cells, crucially involved in the generation of hippocampal theta oscillations, and a local synchronized activation of a subset of inhibitory septal afferents in the hippocampus. The efficacy of the optogenetic rhythm control is verified by a simultaneous monitoring of the local field potential (LFP) across lamina of the CA1 area and/or of neuronal discharge. Using this readily implementable preparation we show efficacy of various optogenetic stimulation protocols for induction of theta oscillations and for the manipulation of their frequency and regularity. Finally, a combination of the theta rhythm control with projection-specific inhibition addresses the readout of particular aspects of the hippocampal synchronization by efferent regions.

We describe the use of optogenetics and electrophysiological recordings for selective manipulations of hippocampal theta oscillations (5-10 Hz) in behaving mice. The efficacy of the rhythm entrainment is monitored using local field potential. A combination of opto- and pharmacogenetic inhibition addresses the efferent readout of hippocampal synchronization.

Optogenetic de arrastamento de Theta Hippocampal oscilações em comportar-se ratos

Extensive data on relationships of neural network oscillations to behavior and organization of neuronal discharge across brain regions call for new tools ...