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 gjerne takke Instituto Gulbenkian de Ciência (IGC) for å gi oss tilgang til en del av det eksperimentelle utstyret som er beskrevet i denne protokollen. Dette arbeidet ble støttet av Portuguese Foundation for Science and Technology (FCT), LISBOA-01-0145-FEDER-007660, PTDC/NEU- NMC/2459/2014, IF/00697/2014 og La Caixa HR17-00595 til PMD og av australian Research Council Future Fellowship (FT170100259) til CKM.

1. Tilberedning av sukrose-gjær (SY) dietter
<ol><li>Vei alle de tørre ingrediensene (agar, gjær, sukrose) for makronæringsstoffbalansering og L3 oppdrett dietter. Mengdene i gram for hver av ingrediensene som trengs for å tilberede 1 liter mat, er angitt i figur 1B. MERK: Ta hensyn til at ca. 13 ml mat er nødvendig for å fylle en 60 mm Petri-tallerken.</li>
	<li>Løs opp alle ingrediensene i sterilt destillert vann (bruk ca. 50% av det totale volumet av vann som trengs for å ti...

<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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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. 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Med denne protokollen kan man teste larvens evne under termogenetisk aktivering av spesifikke nevronale populasjoner for å regulere inntaksnivåene av protein og karbohydrater, to store makronæringsstoffer, når de blir utsatt for dietter av forskjellig P:C-sammensetning. Denne metoden ble testet i sammenheng med en larval foreløpig screening med sikte på å identifisere nevronale populasjoner knyttet til kontroll av matinntak på tvers av dietter av forskjellig makronæringsstoffkvalitet. Dette arbeidet bidrar også...

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 avhengige av et balansert kosthold for å skaffe seg de nødvendige mengdene næringsstoffer for overlevelse, vekst og reproduksjon1. Valget av hva og hvor mye å spise påvirkes av en rekke interagerende faktorer relatert til dyrets indre tilstand, som metthetsnivået og miljøforhold, for eksempel matkvalitet2,3,4,5. Protein og karbohydrater er to store makronæringsstoffer, og det balanserte inntaket er avgjørende for å opprettholde dyrenes fysiologiske prosesser. Derfor er forståelsen av nevrale mekanismer som kontrollerer fôringsatferd og opprettholder et balansert inntak av disse makronæringsstoffene ekstremt relevant. Dette skyldes at livshistorieegenskaper som levetid, fecundity og metabolsk helse påvirkes direkte av nivåene avproteininntaksinntak 6,7,8,9,10.
Bruken av enklere mer gjennomførbare organismer som viser evolusjonært bevarte fôringsvaner med komplekse dyr, inkludert pattedyr, er avgjørende for denne typen studier. Det er viktig at disse enklere dyremodellene gir en god mulighet til å dissekere komplekse biologiske spørsmål i en kostbar, etisk og teknisk mer effektiv sammenheng. I de siste tiårene har Drosophila, med sin kraftige genetiske verktøykasse, intrikate og stereotype oppførsel og bevart arkitektur av perifere og næringssenkende mekanismer med pattedyr, vært en fruktbar modell for atferdsmessige nevrobiologer11. Til syvende og sist er håpet at ved å forstå hvordan matinntaket er regulert i dette dyret, med et enklere nervesystem, kan vi da begynne å løsne nevronale funksjonsfeil som ligger til grunn for menneskelige spiseforstyrrelser.
Studien av nevronale substrater for fôringsatferd er dypt avhengig av å kunne måle dyrenes matinntak samtidig som de manipulerer nevronaktiviteten. På grunn av de minimale mengdene mat som inntas, er kvantifisering av mengden mat spist av fluer ekstremt utfordrende, og alle tilgjengelige metoder gir betydelige begrensninger. Dermed er gullstandarden å bruke en kombinasjon av komplementære metoder12. Voksne fluer har blitt historisk favorisert som en genetisk og atferdsmessig modell. Likevel tilbyr Drosophila larver også muligheter til å undersøke nevronale substrater som koder fôringsadferd. Larval sentralnervesystemet (CNS), med rundt 12.000 nevroner, er betydelig mindre komplekst enn den voksne, som inneholder ca. 150.000 nevroner. Denne lavere kompleksiteten er ikke bare numerisk, men også funksjonell, siden larvatferd er avhengig av enklere lokomotivfunksjoner og sensoriske systemer. Til tross for den tilsynelatende enkelheten i nervesystemet, viser larver fortsatt fullstendig fôringsatferd, og noen metoder for å kvantifisere matinntak i Drosophila larver har blitt beskrevet5,13,14,15. Ved å parre seg med manipulasjoner av nevronaktivitet, kan Drosophila larver utgjøre en svært gjennomførbar modell for å forstå nevral regulering av matinntaket.
Gitt her er en detaljert protokoll for å kvantifisere matinntak i larver utsatt for dietter av forskjellig makronæringsstoffkvalitet. Diettene, såkalte makronæringsstoffbalanseringsdiett, var forskjellig i protein- og karbohydratinnholdet, spesielt med hensyn til forholdet mellom protein og karbohydrat (P:C): 1:1 (proteinrikt kosthold), 1:4 (mellomliggende kosthold) og 1:16 (proteinfattig kosthold), som vist i figur 1A. Kort sagt ble det etablert en kvantitativ no-choice fôringsanalyse ved hjelp av disse tre isocaloric sukrose-gjær (SY)-baserte dietter farget med et blått matfargestoff. Fordi gjærekstrakt og sukrose ble brukt som protein- og karbohydratkilder, og begge inneholder karbohydrater, ble variasjon i P:C-forholdene oppnådd ved å endre balansen mellom disse to komponentene, som tidligere beskrevet16 og som angitt i figur 1B. En skjematisk oversikt over protokollen, som viser de viktigste eksperimentelle trinnene, er tilgjengelig i figur 2.
Denne protokollen ble etablert med sikte på å undersøke rollen til spesifikke nevronpopulasjoner om regulering av larvefôringsnivåer i dietter av forskjellige P: C-forhold og i sammenheng med en termogenetisk nevronskjerm. Et godt karakterisert nevrogenetisk verktøy ble brukt fra TRP-familien (Transient Receptor Potential): Drosophila Transient Receptor Potential channel (dTRPA1), som er en temperatur- og spenningsportert kationkanal, slik at avfyring av handlingspotensialer når omgivelsestemperaturen stiger over 25 °C17. For å uttrykke dTRPA1-transgene, benyttet vi oss av Gal4-linjene basert på cis-regulatoriske regioner fra Drosophila-genomet, etablert i Rubin-laboratoriet, i sammenheng med FlyLight-prosjektet ved Janelia Research Campus18,19.
Selv om protokollen, her beskrevet, er etablert i sammenheng med en aktiveringsskjerm, kan den enkelt tilpasses av eksperimentatoren til andre spesifikke behov eller interesser, nemlig å utføre en undertrykkelsesskjerm ved hjelp av den temperaturfølsomme nevronale lyddemperen ShibireTS20, i tillegg til dTRPA1. Denne og andre tilpasninger diskuteres i protokoll- og diskusjonsseksjonene.

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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

Foraging og fôringsatferd gjør det mulig for dyr å få tilgang til kilder til energi og næringsstoffer som er avgjørende for deres utvikling, helse og kondisjon. Å undersøke nevronal regulering av disse atferdene er avgjørende for forståelsen av de fysiologiske og molekylære mekanismene som ligger til grunn for ernæringsmessig homeostase. Bruken av genetisk gjennomførbare dyremodeller som ormer, fluer og fisk letter i stor grad denne typen studier. I det siste tiåret har fruktfluen Drosophila melanogaster blitt brukt som en kraftig dyremodell av nevrobiologer som undersøker nevronal kontroll av fôring og foraging atferd. Selv om de utvilsomt er verdifulle, undersøker de fleste studier voksne fluer. Her beskriver vi en protokoll som utnytter det enklere larvenervesystemet for å undersøke nevronale substrater som kontrollerer fôringsatferd når larver blir utsatt for dietter som er forskjellige i protein- og karbohydratinnholdet. Våre metoder er basert på en kvantitativ kolorimetrisk no-choice fôringsanalyse, utført i sammenheng med en nevronal termogenetisk aktiveringsskjerm. Som en avlesning ble mengden mat spist av larver over et 1 h intervall brukt når den ble utsatt for en av de tre fargestoffmerkede diettene som varierer i forholdet mellom protein og karbohydrater (P:C). Effekten av denne protokollen er demonstrert i sammenheng med en nevrogenetisk skjerm i larval Drosophila, ved å identifisere kandidat nevronale populasjoner som regulerer mengden mat spist i dietter av forskjellig makronæringsstoffkvalitet. Vi var også i stand til å klassifisere og gruppere genotypene som ble testet i fenotypiske klasser. I tillegg til en kort gjennomgang av de tilgjengelige metodene i litteraturen, diskuteres fordelene og begrensningene ved disse metodene, og det gis også noen forslag om hvordan denne protokollen kan tilpasses andre spesifikke eksperimenter.

Drosophila larver regulerer proteininntaket på bekostning av inntak av overflødige karbohydrater23 (skjematisk tomt i figur 2E). Faktisk har denne prioriteringen av proteininntak blitt observert hos mange andre dyr og kalles proteinet som utnytter24,25.
Ved å dra nytte av denne robuste fôringsadferdsresponsen ble en atferdsbasert skjerm designet med sikte på å identif...

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 protokoll som muliggjør den kolorimetriske kvantifiseringen av mengden mat spist innen et definert tidsintervall av Drosophila melanogaster larver utsatt for dietter av forskjellig makronæringsstoffkvalitet. Disse analysene utføres i sammenheng med en nevronal termogenetisk skjerm.

Kvantifisering av makronæringsstoffer Inntak i en termogenetisk neuronal skjerm ved hjelp av 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

Sammenkoblede Nanoinjection og Elektrofysiologi Assay til skjerm for bioaktivitet av forbindelser ved hjelp av Drosophila melanogaster Giant Fiber System

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 for å vurdere Thermal 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 av Proprioceptors 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 Assosiative Olfactory 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

Fast Micro-iontoforese av glutamat og GABA: Et nyttig verktøy for å etterforske 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

Inducing Plasticity av astrocytic Reseptorer av Manipulering av nevronal utløsning 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

Høyoppløselig Kvantifisering av Lukt styrt Atferd<em&gt; Drosophila melanogaster</em&gt; Bruke<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

Kapillær mater analysen Måler matinntak 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

Kvantifisering av 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 ...

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 ...