Name: quantification of macronutrients intake in a thermogenetic neuronal screen using drosophila larvae
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Description: Watch this Scientific Journal Video about Quantification of Macronutrients Intake in a Thermogenetic Neuronal Screen using Drosophila Larvae at JoVE.com

Vi vil gerne takke Instituto Gulbenkian de Ciência (regeringskonferencen) for at give os adgang til en del af det eksperimentelle udstyr, der er beskrevet i denne protokol. Dette arbejde blev støttet af Det Portugisiske Institut for Videnskab og Teknologi (FCT), LISBOA-01-0145-FEDER-007660, PTDC/NEU- NMC/2459/2014, IF/00697/2014 og La Caixa HR17-00595 til PMD og af et australsk forskningsråds fremtidige stipendium (FT170100259) til CKM.

1. Tilberedning af saccharosegær (SY)
<ol><li>Afveje alle de tørre ingredienser (agar, gær, saccharose) til makronæringsstoffer balancering og L3 opdræt kostvaner. Mængderne i gram for hver af de ingredienser, der er nødvendige for at tilberede 1 L fødevarer, er angivet i figur 1B. BEMÆRK: Tag højde for, at der er behov for ca. 13 mL mad for at fylde en 60 mm petriskål.</li>
	<li>Opløs alle ingredienser i sterilt destilleret vand (brug ca. 50% af den samlede mængde vand, de...

<ol>
	<li>Raubenheimer, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Nature of nutrition - a unifying framework from animal adaptation to human. , (2012).</li><li>Carvahlo, M. J. a., Mirth, C. 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E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Low+protein+intake+is+associated+with+a+major+reduction+in+IGF-1,+cancer,+and+overall+mortality+in+the+65+and+younger+but+not+older+population.">Low protein intake is associated with a major reduction in IGF-1, cancer, and overall mortality in the 65 and younger but not older population.</a> Cell Metabolism. 19 (3), 407-417 (2014).</li><li>Solon-Biet, S. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+ratio+of+macronutrients,+not+caloric+intake,+dictates+cardiometabolic+health,+aging,+and+longevity+in+ad+libitum-fed+mice.">The ratio of macronutrients, not caloric intake, dictates cardiometabolic health, aging, and longevity in ad libitum-fed mice.</a> Cell Metabolism. 19 (3), 418-430 (2014).</li><li>Piper, M. 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B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Small+molecule+drug+screening+in+Drosophila+identifies+the+5HT2A+receptor+as+a+feeding+modulation+target.">Small molecule drug screening in Drosophila identifies the 5HT2A receptor as a feeding modulation target.</a> Scientific Reports. 3, (2013).</li><li>Schoofs, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selection+of+motor+programs+for+suppressing+food+intake+and+inducing+locomotion+in+the+Drosophila+brain.">Selection of motor programs for suppressing food intake and inducing locomotion in the Drosophila brain.</a> PLoS Biology. 12 (6), 1001893 (2014).</li><li>Pocas, G. M., Crosbie, A. E., Mirth, C. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=When+does+diet+matter?+The+roles+of+larval+and+adult+nutrition+in+regulating+adult+size+traits+in+Drosophila+melanogaster.">When does diet matter? The roles of larval and adult nutrition in regulating adult size traits in Drosophila melanogaster.</a> Journal of Insect Physiology. , 104051 (2020).</li><li>Hamada, F. N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+internal+thermal+sensor+controlling+temperature+preference+in+Drosophila.">An internal thermal sensor controlling temperature preference in Drosophila.</a> Nature. 454 (7201), 217-220 (2008).</li><li>Pfeiffer, B. D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tools+for+neuroanatomy+and+neurogenetics+in+Drosophila.">Tools for neuroanatomy and neurogenetics in Drosophila.</a> Proceedings of the National Academy of Sciences of the United States of America. 105 (28), 9715-9720 (2008).</li><li>Jenett, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+GAL4-driver+line+resource+for+Drosophila+neurobiology.">A GAL4-driver line resource for Drosophila neurobiology.</a> Cell Reports. 2 (4), 991-1001 (2012).</li><li>Kitamoto, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Conditional+modification+of+behavior+in+Drosophila+by+targeted+expression+of+a+temperature-sensitive+shibire+allele+in+defined+neurons.">Conditional modification of behavior in Drosophila by targeted expression of a temperature-sensitive shibire allele in defined neurons.</a> Journal of Neurobiology. 47 (2), 81-92 (2001).</li><li>Brand, A. H., Perrimon, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeted+gene+expression+as+a+means+of+altering+cell+fates+and+generating+dominant+phenotypes.">Targeted gene expression as a means of altering cell fates and generating dominant phenotypes.</a> Development. 118 (2), 401-415 (1993).</li><li>Shirangi, T. R., Stern, D. L., Truman, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Motor+control+of+Drosophila+courtship+song.">Motor control of Drosophila courtship song.</a> Cell Reports. 5 (3), 678-686 (2013).</li><li>Mirth, C. M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Food+intake+and+food+choice+are+altered+by+the+developmental+transition+at+critical+weight+in+Drosophila+melanogaster.">Food intake and food choice are altered by the developmental transition at critical weight in Drosophila melanogaster.</a> Animal Behaviour. 126, 195-208 (2017).</li><li>Simpson, S. J., Raubenheimer, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Obesity:+the+protein+leverage+hypothesis.">Obesity: the protein leverage hypothesis.</a> Obesity Reviews. 6 (2), 133-142 (2005).</li><li>Raubenheimer, D., Simpson, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Integrative+models+of+nutrient+balancing:+application+to+insects+and+vertebrates.">Integrative models of nutrient balancing: application to insects and vertebrates.</a> Nutrition Research Reviews. 10 (1), 151-179 (1997).</li><li>Li, H. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+GAL4+driver+resource+for+developmental+and+behavioral+studies+on+the+larval+CNS+of+Drosophila.">A GAL4 driver resource for developmental and behavioral studies on the larval CNS of Drosophila.</a> Cell Reports. 8 (3), 897-908 (2014).</li><li>Bhatt, P. K., Neckameyer, W. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+analysis+of+the+larval+feeding+circuit+in+Drosophila.">Functional analysis of the larval feeding circuit in Drosophila.</a> Journal of Visualized Experiments. (81), e51062 (2013).</li><li>Wong, R., Piper, M. D. W., Blanc, E., Partridge, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pitfalls+of+measuring+feeding+rate+in+the+fruit+fly+Drosophila+melanogaster.">Pitfalls of measuring feeding rate in the fruit fly Drosophila melanogaster.</a> Nature Methods. 5 (3), 214-215 (2008).</li><li>Almeida-Carvalho, M. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Ol1mpiad:+concordance+of+behavioural+faculties+of+stage+1+and+stage+3+Drosophila+larvae.">The Ol1mpiad: concordance of behavioural faculties of stage 1 and stage 3 Drosophila larvae.</a> Journal of Experimental Biology. 220, 2452-2475 (2017).</li><li>Rodrigues, M. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drosophila+melanogaster+larvae+make+nutritional+choices+that+minimize+developmental+time.">Drosophila melanogaster larvae make nutritional choices that minimize developmental time.</a> Journal of Insect Physiology. 81, 69-80 (2015).</li><li>Wong, R., Piper, M. D., Wertheim, B., Partridge, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantification+of+food+intake+in+Drosophila.">Quantification of food intake in Drosophila.</a> PLoS One. 4 (6), 6063 (2009).</li><li>Wu, Q., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Developmental+control+of+foraging+and+social+behavior+by+the+Drosophila+neuropeptide+Y-like+system.">Developmental control of foraging and social behavior by the Drosophila neuropeptide Y-like system.</a> Neuron. 39 (1), 147-161 (2003).</li><li>Wu, Q., Zhang, Y., Xu, J., Shen, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+hunger-driven+behaviors+by+neural+ribosomal+S6+kinase+in+Drosophila.">Regulation of hunger-driven behaviors by neural ribosomal S6 kinase in Drosophila.</a> Proceedings of the National Academy of Sciences of the United States of America. 102 (37), 13289-13294 (2005).</li><li>Lingo, P. R., Zhao, Z., Shen, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Co-regulation+of+cold-resistant+food+acquisition+by+insulin-+and+neuropeptide+Y-like+systems+in+Drosophila+melanogaster.">Co-regulation of cold-resistant food acquisition by insulin- and neuropeptide Y-like systems in Drosophila melanogaster.</a> Neuroscience. 148 (2), 371-374 (2007).</li></ol>

Med denne protokol kunne man teste larvernes evne under termogentisk aktivering af specifikke neuronale populationer til at regulere indtagelsesniveauerne for protein og kulhydrater, to store makronæringsstoffer, når de udsættes for kost af forskellig P:C-sammensætning. Denne metode blev testet i forbindelse med en larveforundersøgelse med det formål at identificere neuronale populationer forbundet med kontrol af fødeindtagelse på tværs af kostvaner af forskellig makronæringskvalitet. Dette arbejde bidrager ogs...

An erratum was issued for:&#160;<a href="https://www.jove.com/t/61323/quantification-macronutrients-intake-thermogenetic-neuronal-screen">Quantification of Macronutrients Intake in a Thermogenetic Neuronal Screen using Drosophila Larvae</a>. A figure was updated.
Figure 1&#160;was updated from:
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/61323/61323fig1.jpg" /> 
Figure 1: The sucrose-yeast (SY) diets used in our protocol. (A) The blue dots represent the isocaloric (248 calories/L) macronutrient balancing diets used in the feeding assay, which differ in the protein to carbohydrate (P:C) ratios: 1:1, 1:4 and 1:16. The beige dot represents the diet used to rear the experimental third-instar larvae (L3), which contained a P:C ratio of 1:2 and a caloric density of 495 calories/L. (B) Detailed composition and nutritional information of the sucrose-yeast (SY) based diets. The components are the same for all the diets: agar, sucrose and yeast. The amount in grams of the components needed to prepare 1 L of diet is shown. Note that 1% (v/v) of blue dye must be added to the macronutrient balancing diets and to the L3 rearing diet nipagin and propionic acid solutions must be added to a final concentration (v/v) of 3% and 0.3%, respectively. <a href="https://www.jove.com/files/ftp_upload/61323/61323fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
to:
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/61323/61323fig1v2.jpg" /> 
Figure 1: The sucrose-yeast (SY) diets used in our protocol. (A) The blue dots represent the isocaloric (248 calories/L) macronutrient balancing diets used in the feeding assay, which differ in the protein to carbohydrate (P:C) ratios: 1:1, 1:4 and 1:16. The beige dot represents the diet used to rear the experimental third-instar larvae (L3), which contained a P:C ratio of 1:2 and a caloric density of 495 calories/L. (B) Detailed composition and nutritional information of the sucrose-yeast (SY) based diets. The components are the same for all the diets: agar, sucrose and yeast. The amount in grams of the components needed to prepare 1 L of diet is shown. Note that 1% (v/v) of blue dye must be added to the macronutrient balancing diets and to the L3 rearing diet nipagin and propionic acid solutions must be added to a final concentration (v/v) of 3% and 0.3%, respectively. <a href="https://www.jove.com/files/ftp_upload/61323/61323fig1v2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

An erratum was issued for:&#160;<a href="https://www.jove.com/t/61323/quantification-macronutrients-intake-thermogenetic-neuronal-screen">Quantification of Macronutrients Intake in a Thermogenetic Neuronal Screen using Drosophila Larvae</a>. A figure was updated.

Erratum: Quantification of Macronutrients Intake in a Thermogenetic Neuronal Screen using Drosophila Larvae

Alle dyr er afhængige af en afbalanceret kost for at erhverve de nødvendige mængder næringsstoffer til overlevelse, vækst og reproduktion1. Valget af hvad og hvor meget at spise er påvirket af en lang række interagerende faktorer relateret til dyrets indre tilstand, som mæthedsniveauet og miljøforholdene, såsom fødevarekvalitet2,3,4,5. Protein og kulhydrater er to store makronæringsstoffer, og dets afbalancerede indtag er afgørende for at opretholde dyrenes fysiologiske processer. Derfor er forståelsen af de neurale mekanismer, der styrer fodringsadfærd og opretholder et afbalanceret indtag af disse makronæringsstoffer, yderst relevant. Dette skyldes, at livshistorieegenskaber som levetid, fecundity og metabolisk sundhed er direkte påvirket af niveauerne afproteinindtagsindtag 6,7,8,9,10.
Brugen af enklere mere tractable organismer, der udviser evolutionært bevarede fodringsvaner med komplekse dyr, herunder pattedyr, er afgørende for denne type undersøgelser. Det er vigtigt, at disse enklere dyremodeller giver en god mulighed for at dissekere komplekse biologiske spørgsmål i en dyr, etisk og teknisk mere effektiv sammenhæng. I de sidste årtier har Drosophila, med sin kraftfulde genetiske værktøjskasse, indviklet og stereotyp adfærd og bevaret arkitektur af perifere og næringsstoffølsomhedsmekanismer med pattedyr, været en frugtbar model for adfærdsmæssige neurobiologer11. I sidste ende er håbet, at ved at forstå, hvordan fødeindtagelse er reguleret i dette dyr, med et enklere nervesystem, kan vi derefter begynde at udrede neuronale funktionsfejl, der ligger til grund for menneskelige spiseforstyrrelser.
Undersøgelsen af neuronale substrater til fodring af adfærd er dybt afhængig af at kunne måle dyrs fødeindtagelse samtidig, mens de manipulerer deres neuronale aktivitet. På grund af de minimale mængder mad, der indtages, er det ekstremt udfordrende at kvantificere mængden af mad, der spises af fluer, og alle tilgængelige metoder udgør i øjeblikket betydelige begrænsninger. Guldstandarden er således at bruge en kombination af komplementære metoder12. Voksne fluer er historisk set blevet foretrukket som en genetisk og adfærdsmæssig model. Ikke desto mindre tilbyder Drosophila larver også muligheder for at undersøge neuronale substrater, der kodper fodringsadfærd. Larve centralnervesystemet (CNS), med omkring 12.000 neuroner, er betydeligt mindre komplekst end den voksne, som indeholder ca. 150.000 neuroner. Denne lavere kompleksitet er ikke kun numerisk, men også funktionel, da larveadfærd er afhængig af enklere lokomotivfunktioner og sensoriske systemer. På trods af den tilsyneladende enkelhed i deres nervesystemer udviser larver stadig fuldstændig fodringsadfærd, og nogle metoder til at kvantificere madindtagelse i Drosophila larver er blevet beskrevet5,13,14,15. Ved at parre sig med manipulationer af neuronal aktivitet kan Drosophila larver udgøre en meget tractable model til forståelse af den neurale regulering af fødeindtagelse.
Forudsat her er en detaljeret protokol til at kvantificere fødeindtagelse i larver udsat for kost af forskellig makronæringsstoffer kvalitet. Kostvanerne, såkaldte makronæringsstoffer balancering kostvaner, afveg i protein og kulhydrater indhold, specielt med hensyn til protein til kulhydrat (P: C) nøgletal: 1:1 (protein-rige kost), 1:4 (mellemliggende kost), og 1:16 (protein-dårlig kost), som vist i figur 1A. Kort, en kvantitativ no-choice fodring assay blev etableret ved hjælp af disse tre isocaloric saccharose-gær (SY)-baserede kostvaner farvet med en blå fødevare farvestof. Da gærekstrakt og saccharose blev anvendt som protein- og kulhydratkilder, og begge indeholder kulhydrater, blev variationen i P:C-forholdet opnået ved at ændre balancen mellem disse to komponenter, som tidligere beskrevet16 og som angivet i figur 1B. En skematisk oversigt over protokollen, der viser de vigtigste eksperimentelle trin, findes i figur 2.
Denne protokol blev oprettet med det formål at undersøge specifikke neuronale populationers rolle i reguleringen af larvefodringsniveauer i kostvaner med forskellige P:C-forhold og i forbindelse med en termogentisk neuronal skærm. Et velkarakterisk neurogenetisk værktøj blev brugt fra Transient Receptor Potential (TRP) familien: Drosophila Transient Receptor Potential kanal (dTRPA1), som er en temperatur og spænding-gated kation kanal, så fyring af handling potentialer, når omgivelsestemperaturerne stiger over 25 ° C17. For at udtrykke dTRPA1 transgene, vi benyttede os af Gal4 linjer baseret på cis-regulerenderegioner fra Drosophila genom, der er etableret i Rubin laboratorium, i forbindelse med FlyLight projektet på Janelia Research Campus18,19.
Selvom protokollen, her beskrevet, er blevet etableret i forbindelse med en aktiveringsskærm, kan den let tilpasses af eksperimentatoren til andre specifikke behov eller interesser, nemlig at udføre en undertrykkelsesskærm ved hjælp af den temperaturfølsomme neuronale lyddæmper ShibireTS20, alternativt til dTRPA1. Denne og andre tilpasninger behandles i protokol- og diskussionsafsnittene.

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			<td height="21" style="height:21px;width:323px;">1.5 mL microtubes</td>
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		<tr height="21">
			<td height="21" style="height:21px;width:323px;">2.0 mL microtubes</td>
			<td style="width:271px;">Sarstedt AG &#38; Co.</td>
			<td style="width:247px;">72.695.500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">60 mm petri dishes</td>
			<td style="width:271px;">Greiner Bio-one, Austria</td>
			<td style="width:247px;">628161</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">96 well microplates</td>
			<td style="width:271px;">Santa Cruz Biotechnology</td>
			<td style="width:247px;">SC-204453</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Agar</td>
			<td style="width:271px;">Pr&#243;-vida, Portugal</td>
			<td style="width:247px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Bench cooler</td>
			<td style="width:271px;">Nalgene, USA</td>
			<td style="width:247px;">Labtop Cooler 5115-0032</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Blue food dye</td>
			<td style="width:271px;">Rayner, Billingshurst, UK</td>
			<td style="width:247px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Cell disruption media</td>
			<td style="width:271px;">Scientific Industries, Inc.</td>
			<td style="width:247px;">888-850-6208</td>
			<td>(0.5 mm glass beads)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Dish weight boats</td>
			<td style="width:271px;">Santa Cruz Biotechnology</td>
			<td style="width:247px;">SC-201606</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:323px;">Embryo collection cage for 60 mm petri dishes</td>
			<td style="width:271px;">Flystuff, Scientific Laboratory Supplies, UK</td>
			<td style="width:247px;">FLY1212 (59-100)</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Featherweight forceps</td>
			<td style="width:271px;">BioQuip Products, USA</td>
			<td style="width:247px;">4750</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Fly food for stocks maintenance</td>
			<td style="width:271px;"></td>
			<td style="width:247px;"></td>
			<td>1 L food contains: 10 g Agar, 100 g Yeast Extract, 50 g Sucrose, 30 mL Nipagin, 3 mL propionic acid</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Forceps #5</td>
			<td style="width:271px;">Dumont</td>
			<td style="width:247px;">0108-5-PS</td>
			<td>Standard tips, INOX, 11cm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Incubator</td>
			<td style="width:271px;">LMS Ltd, UK</td>
			<td style="width:247px;">Series 2, Model 230</td>
			<td>For thermogenetic feeding assay (30&#8728;C)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Incubator</td>
			<td style="width:271px;">Percival Scientific, USA</td>
			<td style="width:247px;">DR36NL</td>
			<td>To stage larvae (19&#8728;C)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Janelia lines</td>
			<td style="width:271px;">Janelia Research Campus</td>
			<td style="width:247px;"></td>
			<td>Detailed information in Table 2</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Macronutrient balancing diets</td>
			<td style="width:271px;"></td>
			<td style="width:247px;"></td>
			<td>Composition and nutritional information in Figure 1</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Methanol</td>
			<td style="width:271px;">VWR</td>
			<td style="width:247px;">CAS number: 67-56-1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Nipagin (Methyl 4-hydroxybenzoate)</td>
			<td style="width:271px;">Sigma-Aldrich</td>
			<td style="width:247px;">H5501</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Nitrile gloves</td>
			<td style="width:271px;">VWR, USA</td>
			<td style="width:247px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:323px;">Refrigerated centrifuge</td>
			<td style="width:271px;">Eppendorf, Germany</td>
			<td style="width:247px;">5804 R / Serial number: 5805CI364293</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Rubin Gal4 ines</td>
			<td style="width:271px;">Janelia Research Campus</td>
			<td style="width:247px;"></td>
			<td>Stoks available at Bloomington Drosophila Stock Center</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">ShibireTS UAS line</td>
			<td style="width:271px;">Bloomington Drosophila Stock Center</td>
			<td style="width:247px;">BDSC number: 66600</td>
			<td>Provided by Carlos Ribeiro Group</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Soft brushes</td>
			<td style="width:271px;"></td>
			<td style="width:247px;"></td>
			<td>For sorting anaesthetised fruit flies</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Spectrophotometer plate reader</td>
			<td style="width:271px;">Thermo Fisher Scientific</td>
			<td style="width:247px;">Multiskan Go 51119300</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Stereo microscope</td>
			<td style="width:271px;">Nikon</td>
			<td style="width:247px;">1016625</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Sucrose</td>
			<td style="width:271px;">Sidul, Portugal</td>
			<td style="width:247px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Third-instar larvae (L3) rearing diet</td>
			<td style="width:271px;"></td>
			<td style="width:247px;"></td>
			<td>Composition and nutritional information in Figure 1</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Timer</td>
			<td style="width:271px;"></td>
			<td style="width:247px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Tissue lyzer / bead beater</td>
			<td style="width:271px;">MP Biomedicals, USA</td>
			<td style="width:247px;">FastPrep-24 6004500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">TRPA1 UAS line</td>
			<td style="width:271px;">Bloomington Drosophila Stock Center</td>
			<td style="width:247px;">BDSC number: 26264</td>
			<td>Expresses TrpA1 under UAS control; may be used to activate neurons experimentally at 25 &#8728;C</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Water bath</td>
			<td style="width:271px;">Sheldon Manufacturing Inc., USA</td>
			<td style="width:247px;">W20M-2 / 03068308 / 9021195</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:323px;">Yeast extract</td>
			<td style="width:271px;">Pr&#243;-vida, Portugal</td>
			<td style="width:247px;"></td>
			<td>51% Protein, 15% Carbohydrate</td>
		</tr>
	</tbody>
</table>

quantification of macronutrients intake in a thermogenetic neuronal screen using drosophila larvae

Fouragering og fodring adfærd giver dyr adgang til energikilder og næringsstoffer afgørende for deres udvikling, sundhed og fitness. Undersøgelse af neuronal regulering af disse adfærdsmåder er afgørende for forståelsen af de fysiologiske og molekylære mekanismer, der ligger til grund for ernæringsmæssige homøostase. Brugen af genetisk tractable dyremodeller som orme, fluer og fisk letter i høj grad disse typer undersøgelser. I det sidste årti er frugtfluen Drosophila melanogaster blevet brugt som en kraftfuld dyremodel af neurobiologer, der undersøger den neuronale kontrol af fodring og fourageringsadfærd. Mens utvivlsomt værdifulde, undersøger de fleste undersøgelser voksne fluer. Her beskriver vi en protokol, der udnytter det enklere larvenervesystem til at undersøge neuronale substrater, der styrer fodringsadfærd, når larver udsættes for kost, der adskiller sig i deres protein- og kulhydratindhold. Vores metoder er baseret på en kvantitativ kolorimetrisk no-choice fodring assay, udført i forbindelse med en neuronal termogentisk-aktivering skærm. Som en aflæsning blev mængden af mad spist af larver over et 1 timers interval brugt, når den blev udsat for en af de tre farvemærkede kostvaner, der varierer i deres protein til kulhydrater (P: C) nøgletal. Effekten af denne protokol demonstreres i forbindelse med en neurogenetisk skærm i larve Drosophila, ved at identificere kandidat neuronale populationer, der regulerer mængden af mad, der spises i kostvaner af forskellig makronæringskvalitet. Vi var også i stand til at klassificere og gruppere genotyper testet i fænotypiske klasser. Ud over en kort gennemgang af de metoder, der i øjeblikket er tilgængelige i litteraturen, diskuteres fordelene og begrænsningerne ved disse metoder, og der gives også nogle forslag til, hvordan denne protokol kan tilpasses andre specifikke eksperimenter.

Drosophila larver regulerer deres proteinindtag på bekostning af indtagelse af overskydende kulhydrater23 (skematisk plot i figur 2E). Faktisk er denne prioritering af proteinindtag blevet observeret hos mange andre dyr og kaldes proteinet, der udnytter24,25.
Ved at drage fordel af denne robuste fodring adfærdsmæssige reaktion, en adfærdsbaseret skærm blev designet til...

Watch this Scientific Journal Video about Quantification of Macronutrients Intake in a Thermogenetic Neuronal Screen using Drosophila Larvae at JoVE.com

Quantification of Macronutrients Intake in a Thermogenetic Neuronal Screen using Drosophila Larvae

Beskrevet her er en protokol, der muliggør den kolorimetriske kvantificering af mængden af mad, der spises inden for et defineret tidsinterval af Drosophila melanogaster larver udsat for kost af forskellig makronæringskvalitet. Disse assays udføres i forbindelse med en neuronal termogentisk skærm.

Kvantificering af makronæringsstoffer Indtag i en termogentisk neuronal skærm ved hjælp af Drosophila Larver

Foraging and feeding behaviors allow animals to access sources of energy and nutrients essential for their development, health, and fitness. Investigating ...

Research

JoVE Journal

Neuroscience

Quantification of Macronutrients Intake in a Thermogenetic Neuronal Screen using Drosophila Larvae

Paired Nanoinjection and Electrophysiology Assay to Screen for Bioactivity of Compounds using the Drosophila melanogaster Giant Fiber System

Paired Nanoinjection and Electrophysiology Assay to Screen for Bioactivity of Compounds using the Drosophila melanogaster Giant Fiber System

Parret Nanoinjection og Elektrofysiologi Assay til screening for bioaktivitet af forbindelser ved hjælp af Drosophila melanogaster Giant fibersystem

Screening compounds for in vivo activity can be used as a first step to identify candidates that may be developed into pharmacological agents1,2. We ...

Local and Global Methods of Assessing Thermal Nociception in Drosophila Larvae

Local and Global Methods of Assessing Thermal Nociception in Drosophila Larvae

Lokale og globale metoder til vurdering Termisk nociception i<em&gt; Drosophila</em&gt; Larver

In this article, we demonstrate assays to study thermal nociception in Drosophila larvae. One assay involves spatially-restricted (local) stimulation of ...

Visualization of Proprioceptors in Drosophila Larvae and Pupae

Visualization of Proprioceptors in Drosophila Larvae and Pupae

Visualisering af proprioceptorer i<em&gt; Drosophila</em&gt; Larver og pupper

Proprioception is the ability to sense the motion, or position, of body parts by responding to stimuli arising within the body. In fruitflies and other ...

Appetitive Associative Olfactory Learning in Drosophila Larvae

Appetitive Associative Olfactory Learning in Drosophila Larvae

Appetitive Associativ olfaktorisk læring i<em&gt; Drosophila</em&gt; Larver

In the following we describe the methodological  details of appetitive associative olfactory learning in Drosophila larvae. The setup, in combination with ...

Fast Micro-iontophoresis of Glutamate and GABA: A Useful Tool to Investigate Synaptic Integration

Hurtig Mikro-iontophoresis af glutamat og GABA: et nyttigt redskab til Undersøge Synaptic Integration

One of the fundamental interests in neuroscience is to understand the integration of excitatory and inhibitory inputs along the very complex structure of ...

Inducing Plasticity of Astrocytic Receptors by Manipulation of Neuronal Firing Rates

Inducerende plasticitet astrocytisk receptorer ved manipulation af neuronfyring priser

Close to two decades of research has established that astrocytes in situ and in vivo express numerous G protein-coupled receptors (GPCRs) that can be ...

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

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

Høj opløsning Kvantificering af Lugt-styrede adfærd i<em&gt; Drosophila melanogaster</em&gt; Brug af<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 ...

The CApillary FEeder Assay Measures Food Intake in Drosophila melanogaster

The CApillary FEeder Assay Measures Food Intake in Drosophila melanogaster

Den kapillære Feeder-analysen Måler fødeindtagelse i<em&gt; Drosophila melanogaster</em

For most animals, feeding is an essential behavior for securing survival, and it influences development, locomotion, health and reproduction. Ingestion of ...

Quantification of Drosophila Grooming Behavior

Kvantificering af Drosophila Grooming Adfærd

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

Novel Assay for Cold Nociception in Drosophila Larvae

Novel Assay for Cold Nociception in Drosophila Larvae

Novel analyse for Cold Nociception i<em&gt; Drosophila</em&gt; Larver

How organisms sense and respond to noxious temperatures is still poorly understood. Further, the mechanisms underlying sensitization of the sensory ...