Diese Arbeit wurde vom National Institutes of Health gewährt F32 NS078958 (DTB) und R01 AG033620 (BG).

1. Montieren Flug Tester <ol><li> Sichere Flug Zylinder Ring Stand 1 mit Spannketten. (Lassen Sie ca. 3 cm unterhalb des Zylinders für wiegen Gericht.) (Anmerkung: Der Flug Zylinder wir benutzen, ist 90 cm lang, mit einem Durchmesser von 13,5 cm.) </li><li> Legen Sie wiegen Schale mit einer dünnen Schicht von Mineralöl unter der Flug Zylinder. </li><li> Sichere Trichter Ring Stand 2 mit einem Klemmring und Klauenklemme. Einstellen der Höhe des Trichters, so daß der Boden des Trichters ist bündig mit der Oberseite des Luftzylinders. (Anmerkung: der Spitzendurchmesser des Trichters muß kleiner als der Außendurchmesser der Röhrchen in die Fallrohre angeordnet, so daß die Ampullen nicht durchfallen können.) </li><li> Legen Fallrohr von oben in den Trichter und befestigen Sie sie mit einer Klaue Klemme. (Hinweis: Wir verwenden ein Fallrohr, die 25 cm lang ist Dropping fliegen haltigen Fläschchen aus dieser Höhe ermöglicht die konsistente Ausstoß aller Fliegen mit gleichmäßiger Kraft Der Innendurchmesser des Fallrohres sollte sligh sein..tly größer als der Außendurchmesser der Ampulle, damit das Fläschchen fallen frei.) </li><li> Schneiden Sie Polyacrylamid-Blatt (n) auf die richtige Größe. (Hinweis: Um beim Einführen und Entfernen der Folie zu erleichtern, sollte die Breite geringfügig kleiner als der Innenumfang des Luftzylinders sein). </li><li> Tragen Sie eine dünne Schicht der Tangle-Falle auf das Blatt. Man lässt 1 h vor der Verwendung zu sitzen. (Hinweis: Lassen Sie genug Platz am oberen und unteren Rand des Blattes (ca. 3 cm) unbeschichtet, um das Blatt zu Einfügen / Entfernen zu erreichen.) </li><li> Legen Sie die Polyacrylamid-Blatt in der Flug Zylinder. </li><li> Montieren Sie die Kamera Spur mit Pinien Halterungen. (Hinweis: dafür sorgen, dass der Boden der Spur kann die Kamera ohne die Blockierung der Linse unterstützt siehe Abbildung 1B.). </li><li> In Stopfen und festschrauben. (Anmerkung: Ort, die Anschläge an Orten, damit die Kamera die gesamte Kunststofffolie in Panoramamodus anzeigen wird.) </li></ol> 2. Führen Experiment <ol> &lt;li&gt; Sammeln Fläschchen entfernt getestet werden. Die besten Ergebnisse erzielen, verwenden Sie nicht mehr als 20 Fliegen / Fläschchen. </li><li> Klopfen Sie leicht nach unten fliegt der Fläschchen, trennen, dann in Fallrohr stecken und lassen Fläschchen. (Anmerkung: Das Fläschchen fällt das Fallrohr, bis er den schmalen Trichteröffnung trifft, wenn die Ampulle trifft den Trichter, sind die Fliegen in die Flucht Zylinder ausgestoßen.). </li><li> Heben Sie das Fallrohr, um die leere Flasche zu entfernen. (Hinweis: Mehrere Fläschchen von Fliegen aus dem gleichen Testgruppe können auf einem einzigen Blatt untersucht werden Polyacrylamid Wir finden, dass bis zu 200 Fliegen (10 Fläschchen mit je 20 entfernt) kann getestet und leicht abgebildet werden auf einem einzigen Blatt.. </li><li> Entfernen Sie die Plastikfolie und legen Sie es auf eine ebene weiße Fläche. (Anmerkung: weißes Plakat Bord verwendet werden, wenn Tischplatten sind dunkel gefärbt.) </li><li> Montieren Sie die Kamera Spur über die Kunststofffolie. Die Kamera sollte ausreichend hoch über dem Blatt, um sowohl den oberen und unteren Rand des Blattes in dem Sichtfeld zu haben. </li><li> Schieben Sie die Kamera entlang the Spur, während die &quot;Capture&quot;-Taste gedrückt halten, um ein Panoramabild zu erwerben. </li><li> Die Anzahl der Fliegen Landung in der Öl kann manuell für jeden Versuch gezählt. </li><li> Wiederholen Sie die Schritte 2,2-2,7 für alle Bedingungen in einem gegebenen Experiment. Die Fliegen können aus dem Bogen zwischen jedem Versuch entfernt werden. Alternativ können mehrere Folien verwendet werden, mit einem neuen Blatt für jeden Versuch. </li></ol> 3. Data Collection <ol><li> Bilddateien öffnen mit ImageJ Software. </li><li> Crop Bilder, wenn notwendig, nur die Landefläche umfassen. (Dies ist der Bereich, in Tangle-Trap-beschichtet.) </li><li> Konvertieren von Bildern in 8-Bit-Graustufen. </li><li> Erstellen Sie eine &quot;Schwelle&quot; zu filtern, die weißen Hintergrund. (Bild → Einstellen → Threshold). </li><li> Stellen Sie die Parameter, jede Fliege über das Menü &quot;Analyse-Partikel&quot; zu identifizieren. (→ Analysieren Analysieren Partikel) Definieren Sie die verwendet werden, um ein Teilchen zu identifizieren Parameter. Mit unserem eingerichtet ist, finden wir, dass mit einFläche von 5-90 Pixel 2 und einer Rundheit von 0,4-1,0 wird genau zu identifizieren, alle Proben. </li><li> Messen Sie die Lage der einzelnen Fliege unter Verwendung der erzeugten Liste von Koordinaten für jedes Teilchen. Die x-Koordinate in Pixeln in Zentimeter umgerechnet werden, um die Landehöhe zu berechnen. </li><li> Importieren Tabelle in einer Tabellenkalkulation (zB Microsoft Excel). </li></ol>

<ol>
	<li>Benzer, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+dissection+of+behavior.">Genetic dissection of behavior.</a> Sci. Am. 229, 24-37 (1973).</li><li>Ali, Y. O., Escala, W., Ruan, K., Zhai, R. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assaying+locomotor,+learning,+and+memory+deficits+in+Drosophila+models+of+neurodegeneration.">Assaying locomotor, learning, and memory deficits in Drosophila models of neurodegeneration.</a> J. Vis. Exp. , e2504 (2011).</li><li>de Vries, S. E., Clandinin, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optogenetic+Stimulation+of+Escape+Behavior+in+Drosophila+melanogaster.">Optogenetic Stimulation of Escape Behavior in Drosophila melanogaster.</a> J. Vis. Exp. , e50192 (2013).</li><li>Mundiyanapurath, S., Certel, S., Kravitz, E. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Studying+aggression+in+Drosophila+(fruit+flies).">Studying aggression in Drosophila (fruit flies).</a> J. Vis. Exp. , e155 (2007).</li><li>Nichols, C. D., Becnel, J., Pandey, U. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Methods+to+assay+Drosophila+behavior.">Methods to assay Drosophila behavior.</a> J. Vis. Exp. , e3795 (2012).</li><li>Shiraiwa, T., Carlson, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Proboscis+extension+response+(PER)+assay+in+Drosophila.">Proboscis extension response (PER) assay in Drosophila.</a> J. Vis. Exp. , e193 (2007).</li><li>Lloyd, T. E., Taylor, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flightless+flies:+Drosophila+models+of+neuromuscular+disease.">Flightless flies: Drosophila models of neuromuscular disease.</a> Ann. N.Y. Acad. Sci. 1184, e1-e20 (2010).</li><li>Atkinson, N. S., 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=Molecular+separation+of+two+behavioral+phenotypes+by+a+mutation+affecting+the+promoters+of+a+Ca-activated+K+channel.">Molecular separation of two behavioral phenotypes by a mutation affecting the promoters of a Ca-activated K channel.</a> J. Neurosci. 20, 2988-2993 (2000).</li><li>Atkinson, N. S., Robertson, G. A., Ganetzky, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+component+of+calcium-activated+potassium+channels+encoded+by+the+Drosophila+slo+locus.">A component of calcium-activated potassium channels encoded by the Drosophila slo locus.</a> Science. 253, 551-555 (1991).</li><li>Elkins, T., Ganetzky, B., Wu, C. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Drosophila+mutation+that+eliminates+a+calcium-dependent+potassium+current.">A Drosophila mutation that eliminates a calcium-dependent potassium current.</a> Proc. Natl. Acad. Sci. U.S.A. 83, 8415-8419 (1986).</li><li>Gargano, J. W., Martin, I., Bhandari, P., Grotewiel, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+iterative+negative+geotaxis+(RING):+a+new+method+for+assessing+age-related+locomotor+decline+in+Drosophila.">Rapid iterative negative geotaxis (RING): a new method for assessing age-related locomotor decline in Drosophila.</a> Exp. Gerontol. 40, 386-395 (2005).</li><li>Fry, S. N., Rohrseitz, N., Straw, A. D., Dickinson, M. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visual+control+of+flight+speed+in+Drosophila+melanogaster.">Visual control of flight speed in Drosophila melanogaster.</a> J. Exp. Biol. 212, 1120-1130 (2009).</li><li>Mronz, M., Lehmann, F. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+free-flight+response+of+Drosophila+to+motion+of+the+visual+environment.">The free-flight response of Drosophila to motion of the visual environment.</a> J. Exp. Biol. 211, 2026-2045 (2008).</li></ol>

Die Autoren haben keine Interessenkonflikte offen zu legen.

Mit den hier beschriebenen Methoden haben wir in der Lage, schnell zu beurteilen Flugleistung aus einer großen Anzahl von Drosophila-Mutanten, die Bereitstellung effizienter als bisher möglich. Für unsere Experimente haben wir routinemäßig zu trennen Männer und Frauen, und heben Sie sie bei geringer Dichte (weniger als 20 Fliegen / Fläschchen), um Aggression, die Flügel Schaden zu begrenzen. Ein weiterer wichtiger Aspekt ist für die Unterschiede in der Flugleistung wegen der unterschiedlichen genetisch...

Drosophila ist seit langem verwendet, um die genetischen Grundlagen von Verhalten 1 zu studieren, und Forscher haben eine Reihe von Möglichkeiten, um verschiedene Arten von Verhalten analysieren 2-6 entwickelt. Fliegen haben sich als besonders nützlich, um nützliche Modelle von neuromuskulären Erkrankungen 7 gewesen. Ein gemeinsamer Test verwendet, um Bewegungsverhalten zu studieren, ist Flugleistung. Die ursprünglichen Flug Tester ist nützlich für die Identifizierung Flug Mutanten und quantitative Bewertung der Flugfähigkeit ein, aber es hat einige Mängel, die seine Anwendung für Hochdurchsatz-Screening zu begrenzen: die Verwendung von Öl-beschichteten Zylindern ist chaotisch und umständlich, bestimmte Features wie die Länge des Zylinders und der Einführung der Fliegen in das Rohr mit variabler Kraft zu reduzieren quantitative Genauigkeit, und es ist schwierig, lebende entfernt von dem Testgerät zu erholen. Um diese Einschränkungen zu überwinden, haben wir den Flug Tester modifiziert, um eine Reihe von Verbesserungen enthalten. Wir haben einen &quot;Tropfen tuwerden &quot;, um Fliegen, um die Variabilität zwischen den Experimenten und Benutzer zu beseitigen einzuführen. Wir verwenden abnehmbaren Acrylplatten mit einem Klebstoff, der für eine einfachere Bereinigung und Wiederherstellung einzelner Fliegen ermöglicht beschichtet. Wir haben die Länge der Flugrohr erhöht, um quantitative Genauigkeit und Zuverlässigkeit zu verbessern. Schließlich verwenden wir eine Digitalkamera und Bildbearbeitungssoftware, um die Landung Höhen von Fliegen zu berechnen. Wir glauben, diese Verbesserungen sinnvoll, jedem Labor interessiert bei der Durchführung von Großbildschirme für genetische Defekte in Flugleistung sein.

<table border="0" cellpadding="0" cellspacing="0" width="704">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">Putty knife</td>
			<td style="width:171px;">Home Depot</td>
			<td style="width:132px;">630147</td>
			<td style="width:185px;"><a href="http://www.homedepot.com">www.homedepot.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">Pine back band moulding ( x2 )</td>
			<td style="width:171px;">Home Depot</td>
			<td style="width:132px;">156469</td>
			<td><a href="http://www.homedepot.com">www.homedepot.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">Furring Strip Board</td>
			<td style="width:171px;">Home Depot</td>
			<td style="width:132px;">164704</td>
			<td><a href="http://www.homedepot.com">www.homedepot.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">Tangle Trap Insect Trap Coating</td>
			<td style="width:171px;">BioControl Network</td>
			<td style="width:132px;">268941</td>
			<td><a href="http://www.biconet.com">www.biconet.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">Laptop Computer </td>
			<td style="width:171px;">Apple</td>
			<td style="width:132px;">_</td>
			<td><a href="http://www.apple.com/mac/">www.apple.com/mac/</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">mineral oil</td>
			<td style="width:171px;">Fisher Scientific</td>
			<td style="width:132px;">BP26291</td>
			<td><a href="http://www.fishersci.com">www.fishersci.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">white poster board</td>
			<td style="width:171px;">Staples</td>
			<td style="width:132px;">247403</td>
			<td><a href="http://www.staples.com">www.staples.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">polystyrene weighing dish</td>
			<td style="width:171px;">Fisher Scientific</td>
			<td style="width:132px;">S67091A</td>
			<td><a href="http://www.fishersci.com">www.fishersci.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">ImageJ Software</td>
			<td style="width:171px;">National Institutes of Health</td>
			<td style="width:132px;">_</td>
			<td>http://rsb.info.nih.gov/ij/</td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">digital camera</td>
			<td style="width:171px;">Sony</td>
			<td style="width:132px;">DSC-TX7</td>
			<td style="width:185px;"><a href="http://www.store.sony.com">www.store.sony.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">fine forceps</td>
			<td style="width:171px;">Fine Science Tools</td>
			<td style="width:132px;">_</td>
			<td><a href="http://www.finescience.com">www.finescience.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">polycarbonate cylinder (drop tube)</td>
			<td style="width:171px;">mcMaster-Carr</td>
			<td style="width:132px;">8585K62</td>
			<td><a href="http://www.mcmaster.com">www.mcmaster.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">flight cylinder (acrylic)</td>
			<td style="width:171px;">mcMaster-Carr</td>
			<td style="width:132px;">8486K943</td>
			<td><a href="http://www.mcmaster.com">www.mcmaster.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">polycarbonate sheets</td>
			<td style="width:171px;">mcMaster-Carr</td>
			<td style="width:132px;">85585K25</td>
			<td><a href="http://www.mcmaster.com">www.mcmaster.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">ring stand (x2)</td>
			<td style="width:171px;">Fisher Scientific</td>
			<td style="width:132px;">S47808</td>
			<td><a href="http://www.fishersci.com">www.fishersci.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">ring support</td>
			<td style="width:171px;">Fisher Scientific</td>
			<td style="width:132px;">S47791</td>
			<td><a href="http://www.fishersci.com">www.fishersci.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">Three-prong extension clamps (x2)</td>
			<td style="width:171px;">Fisher Scientific</td>
			<td style="width:132px;">05-769-7Q</td>
			<td><a href="http://www.fishersci.com">www.fishersci.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">funnel</td>
			<td style="width:171px;">Fisher Scientific</td>
			<td style="width:132px;">10-500-3</td>
			<td><a href="http://www.fishersci.com">www.fishersci.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">chain clamps (x2)</td>
			<td style="width:171px;">VWR</td>
			<td style="width:132px;">21573-275</td>
			<td><a href="http://www.vwr.com">www.vwr.com</a></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:216px;">glass vials</td>
			<td style="width:171px;">VWR</td>
			<td style="width:132px;">66020-198</td>
			<td><a href="http://www.vwr.com/">www.vwr.com</a></td>
		</tr>
	</tbody>
</table>

an improved method for accurate and rapid measurement of flight performance in drosophila

Drosophila hat sich als ein nützliches Modellsystem für die Analyse des Verhaltens, einschließlich der Flug sein. Die ersten Flug Tester beteiligt Drop fliegt in eine Öl-beschichtet Messzylinder; Landehöhe ein Maß für die Flugleistung durch die Beurteilung, wie weit entfernt fallen wird vor der Herstellung genug Schub, um den Kontakt mit der Wand des Zylinders zu machen. Hier beschreiben wir eine aktualisierte Version der Flug-Tester mit vier großen Verbesserungen. Zuerst haben wir eine &quot;Fallrohr&quot;, um sicherzustellen, dass alle Fliegen geben Sie die Flug Zylinder bei einer ähnlichen Geschwindigkeit zwischen Studien, wodurch die Variabilität zwischen den Nutzern. Zweitens, die Ölschicht ersetzt wir mit herausnehmbaren Kunststoffplatten in Tangle-Falle, einem Klebstoff entwickelt, um lebende Insekten einzufangen beschichtet. Drittens verwenden wir einen Zylinder mehr, um genauere Unterscheidung der Flugfähigkeit zu ermöglichen. Vierte verwenden wir eine Digitalkamera und Bildbearbeitungssoftware, um die Scoring der Flugleistung zu automatisieren. Diese Verbesserungen ermöglichen die Rap-id, quantitative Bewertung der Flugverhalten, nützlich für große Datenmengen und große genetische Bildschirme.

<html> 1A zeigt eine schematische Darstellung des aktuellen Flug Tester Montage. 1B zeigt die Spur Design ermöglichen die Kamera zu einem Panoramabild, ohne dabei das Sichtfeld zu nehmen. Repräsentative Ergebnisse sind in Abbildung 2, wo die Flugleistung der Langweiler mutierten Fliegen, die eine bekannte Flug Defekt 8-10 haben, werden zu Wildtyp-Canton-S fliegt Vergleich gezeigt. Kontrolle fliegt konsequent landen in der Nähe der Oberseit...

Watch this Scientific Journal Video about An Improved Method for Accurate and Rapid Measurement of Flight Performance in Drosophila at JoVE.com

An Improved Method for Accurate and Rapid Measurement of Flight Performance in Drosophila

Hier beschreiben wir ein Verfahren zum schnellen und genauen Messung der Flugleistung in Drosophila, was eine Hochdurchsatz-Screening.

Ein verbessertes Verfahren für genaue und schnelle Messung der Flugleistung in<em&gt; Drosophila</em

Drosophila has proven to be a useful model system for analysis of behavior, including flight. The initial flight tester involved dropping flies into an ...

an-improved-method-for-accurate-rapid-measurement-flight-performance

Research

JoVE Journal

Biology

An Improved Method for Accurate and Rapid Measurement of Flight Performance in Drosophila

11.6K Aufrufe.  University of Wisconsin-Madison.  Hier beschreiben wir ein Verfahren zum schnellen und genauen Messung der Flugleistung in Drosophila, was eine Hochdurchsatz-Screening. 

Serie: An Improved Method for Accurate and Rapid Measurement of Flight Performance in Drosophila

Pyrosequencing: A Simple Method for Accurate Genotyping

Pharmacogenetic research benefits first-hand from the abundance of information provided by the completion of the Human Genome Project. With such a tremendous amount of data available comes an explosion of genotyping methods. Pyrosequencing(R) is one of the most thorough yet simple methods to date used to analyze polymorphisms. It also has the ability to identify tri-allelic, indels, short-repeat polymorphisms, along with determining allele percentages for methylation or pooled sample assessment. In addition, there is a standardized control sequence that provides internal quality control. This method has led to rapid and efficient single-nucleotide polymorphism evaluation including many clinically relevant polymorphisms. The technique and methodology of Pyrosequencing is explained.


Pyrosequencing(R) is one of the most thorough yet simple methods to date used to analyze polymorphisms. This method has led to rapid and efficient single-nucleotide polymorphism evaluation including many clinically relevant polymorphisms. The technique and methodology of Pyrosequencing is explained.

Pyrosequencing: Eine einfache Methode für genaue Genotypisierung

Pharmacogenetic research benefits first-hand from the abundance of information provided by the completion of the Human Genome Project. With such a ...

Forschung

Biologie

High-resolution Measurement of Odor-Driven Behavior in Drosophila Larvae

Olfactory responses in Drosophila larvae have been traditionally studied in Petri dishes comprising a single peripheral odor source. In this behavioral paradigm, the experimenter usually assumes that the rapid diffusion of odorant molecules from the source leads to the creation of a stable gradient in the dish. To establish a quantitative correlation between sensory inputs and behavioral responses, it is necessary to achieve a more thorough characterization of the odorant stimulus conditions. In this video article, we describe a new method allowing the construction of odorant gradients with stable and controllable geometries. We briefly illustrate how these gradients can be used to screen for olfactory defects (full and partial anosmia) and to study more subtle features of chemotaxis behavior.

In this video article, we describe a new method allowing the construction of odorant gradients with stable and controllable geometries. We briefly illustrate how these gradients can be used to screen for olfactory defects (full and partial anosmia) and to study more subtle features of chemotaxis behavior.

Hochauflösende Messung von Odor-Driven Behavior in Drosophila-Larven

Olfactory responses in Drosophila larvae have been traditionally studied in Petri dishes comprising a single peripheral odor source. In this behavioral ...

A Magnetic Tether System to Investigate Visual and Olfactory Mediated Flight Control in Drosophila

It has been clear for many years that insects use visual cues to stabilize their heading in a wind stream. Many animals track odors carried in the wind. As such, visual stabilization of upwind tracking directly aids in odor tracking. But do olfactory signals directly influence visual tracking behavior independently from wind cues? Also, the recent deluge of research on the neurophysiology and neurobehavioral genetics of olfaction in Drosophila has motivated ever more technically sophisticated and quantitative behavioral assays. Here, we modified a magnetic tether system originally devised for vision experiments by equipping the arena with narrow laminar flow odor plumes. A fly is glued to a small steel pin and suspended in a magnetic field that enables it to yaw freely. Small diameter food odor plumes are directed downward over the fly s head, eliciting stable tracking by a hungry fly. Here we focus on the critical mechanics of tethering, aligning the magnets, devising the odor plume, and confirming stable odor tracking.

Here we describe how to tether a fly in an olfactory magnetic-tether (OMT) apparatus. We describe how to align the rare-earth magnets and odor ports, and how to set mass flow rates for both the stimulus delivery and vacuum suction to achieve optimal odor tracking.

A Magnetic Tether System zur visuellen und olfaktorischen Mediated Flight Control in Drosophila Untersuchen

It has been clear for many years that insects use visual cues to stabilize their heading in a wind stream. Many animals track odors carried in the wind. ...

Visually Mediated Odor Tracking During Flight in Drosophila

Flying insects use visual cues to stabilize their heading in a wind stream. Many animals additionally track odors carried in the wind. As such, visual stabilization of upwind tracking directly aids in odor tracking. But do olfactory signals directly influence visual tracking behavior independently from wind cues? Additionally, recent advances in olfactory molecular genetics and neurophysiology have motivated novel quantitative behavioral analyses to assess the behavioral influence of (e.g.) genetically inactivating specific olfactory activation circuits. We modified a magnetic tether system originally devised for vision experiments by equipping the arena with narrow laminar flow odor plumes. Here we focus on experiments that can be performed after a fly is tethered and is able to navigate in the magnetic arena. We show how to acquire video images optimized for measuring body angle, how to judge stable odor tracking, and we illustrate two experiments to examine the influence of visual cues on odor tracking.

Here we describe how to optimize the acquired video image for an olfactory magnetic-tether (OMT) apparatus. We also describe two sample experimental protocols for studying visuo-olfactory fusion.

Visuell vermittelte Odor-Tracking während des Fluges in Drosophila

Flying insects use visual cues to stabilize their heading in a wind stream. Many animals additionally track odors carried in the wind. As such, visual ...

An Improved Method of RNA Isolation from Loblolly Pine (P. taeda L.) and Other Conifer Species

Tissues isolated from conifer species, particularly those belonging to the Pinaceae family, such as loblolly pine (Pinus taeda L.), contain high concentrations of phenolic compounds and polysaccharides that interfere with RNA purification. Isolation of high-quality RNA from these species requires rigorous tissue collection procedures in the field and the employment of an RNA isolation protocol comprised of multiple organic extraction steps in order to isolate RNA of sufficient quality for microarray and other genomic analyses. The isolation of high-quality RNA from field-collected loblolly pine samples can be challenging, but several modifications to standard tissue and RNA isolation procedures greatly improve results. The extent of general RNA degradation increases if samples are not properly collected and transported from the field, especially during large-scale harvests. Total RNA yields can be increased significantly by pulverizing samples in a liquid nitrogen freezer mill prior to RNA isolation, especially when samples come from woody tissues. This is primarily due to the presence of oxidizing agents, such as phenolic compounds, and polysaccharides that are both present at high levels in extracts from the woody tissues of most conifer species. If not removed, these contaminants can carry over leading to problems, such as RNA degradation, that result in low yields and a poor quality RNA sample. Carryover of phenolic compounds, as well as polysaccharides, can also reduce or even completely eliminate the activity of reverse transcriptase or other polymerases commonly used for cDNA synthesis. In particular, RNA destined to be used as template for double-stranded cDNA synthesis in the generation of cDNA libraries, single-stranded cDNA synthesis for PCR or qPCR's, or for the synthesis of microarray target materials must be of the highest quality if researchers expect to obtain optimal results. RNA isolation techniques commonly employed for many other plant species are often insufficient in their ability to remove these contaminants from conifer samples and thus do not yield total RNA samples suitable for downstream manipulations. In this video we demonstrate methods for field collection of conifer tissues, beginning with the felling of a forty year-old tree, to the harvesting of phloem, secondary xylem, and reaction wood xylem. We also demonstrate an RNA isolation protocol that has consistently yielded high-quality RNA for subsequent enzymatic manipulations.

An Improved Method of RNA Isolation from Loblolly Pine P. taeda L. and Other Conifer Species

Many plant tissues, including phloem and xylem from loblolly pine (Pinus taeda L.), contain high levels of phenolics and polysaccharides that interfere with RNA purification. This presentation discusses techniques for the harvest of field-grown tissues and isolation of RNA of sufficient quality for microarrays and other genomic analyses.

Ein verbessertes Verfahren zur RNA-Isolierung aus Loblolly Pine ( P. taeda L.) und andere Nadelbaumarten

Tissues isolated from conifer species, particularly those belonging to the Pinaceae family, such as loblolly pine (Pinus taeda L.), contain high ...

Endurance Training Protocol and Longitudinal Performance Assays for Drosophila melanogaster

One of the most pressing problems facing modern medical researchers is the surging levels of obesity, with the consequent increase in associated disorders such as diabetes and cardiovascular disease 1-3. An important topic of research into these associated health problems involves the role of endurance exercise as a beneficial intervention.
Exercise training is an inexpensive, non-invasive intervention with several beneficial results, including reduction in excess body fat 4, increased insulin sensitivity in skeletal muscle 5, increased anti-inflammatory and antioxidative responses 6, and improved contractile capacity in cardiomyocytes 7. Low intensity exercise is known to increase mitochondrial activity and biogenesis in humans 8 and mice, with the transcriptional coactivator PGC1-&alpha; as an important intermediate 9,10. 
Despite the importance of exercise as a tool for combating several important age-related diseases, extensive longitudinal genetic studies have been impeded by the lack of an endurance training protocol for a short-lived genetic model species. The variety of genetic tools available for use with Drosophila, together with its short lifespan and inexpensive maintenance, make it an appealing model for further study of these genetic mechanisms. With this in mind we have developed a novel apparatus, known as the Power Tower, for large scale exercise-training in Drosophila melanogaster 11. The Power Tower utilizes the flies' instinctive negative geotaxis behavior to repetitively induce rapid climbing. Each time the machine lifts, then drops, the platform of flies, the flies are induced to climb. Flies continue to respond as long as the machine is in operation or until they become too fatigued to respond. Thus, the researcher can use this machine to provide simultaneous training to large numbers of age-matched and genetically identical flies. Additionally, we describe associated assays useful to track longitudinal progress of fly cohorts during training.

Endurance Training Protocol and Longitudinal Performance Assays for Drosophila melanogaster

We describe the first endurance training protocol for an important genetic model species, Drosophila melanogaster, and outline several assays to chart improvements in mobility following training.

Ausdauertraining Protokoll und Längs-Performance-Assays für Drosophila melanogaster

One of the most pressing problems facing modern medical researchers is the surging levels of obesity, with the consequent increase in associated disorders ...

Measurement of Lifespan in Drosophila melanogaster

Aging is a phenomenon that results in steady physiological deterioration in nearly all organisms in which it has been examined, leading to reduced physical performance and increased risk of disease. Individual aging is manifest at the population level as an increase in age-dependent mortality, which is often measured in the laboratory by observing lifespan in large cohorts of age-matched individuals. Experiments that seek to quantify the extent to which genetic or environmental manipulations impact lifespan in simple model organisms have been remarkably successful for understanding the aspects of aging that are conserved across taxa and for inspiring new strategies for extending lifespan and preventing age-associated disease in mammals.
The vinegar fly, Drosophila melanogaster, is an attractive model organism for studying the mechanisms of aging due to its relatively short lifespan, convenient husbandry, and facile genetics. However, demographic measures of aging, including age-specific survival and mortality, are extraordinarily susceptible to even minor variations in experimental design and environment, and the maintenance of strict laboratory practices for the duration of aging experiments is required. These considerations, together with the need to practice careful control of genetic background, are essential for generating robust measurements. Indeed, there are many notable controversies surrounding inference from longevity experiments in yeast, worms, flies and mice that have been traced to environmental or genetic artifacts1-4. In this protocol, we describe a set of procedures that have been optimized over many years of measuring longevity in Drosophila using laboratory vials. We also describe the use of the dLife software, which was developed by our laboratory and is available for download (<a href="http://sitemaker.umich.edu/pletcherlab/software">http://sitemaker.umich.edu/pletcherlab/software</a>). dLife accelerates throughput and promotes good practices by incorporating optimal experimental design, simplifying fly handling and data collection, and standardizing data analysis. We will also discuss the many potential pitfalls in the design, collection, and interpretation of lifespan data, and we provide steps to avoid these dangers.

Measurement of Lifespan in Drosophila melanogaster

Drosophila melanogaster is a powerful model organism for exploring the molecular basis of longevity regulation. This protocol will discuss the steps involved in generating a reproducible, population-based measurement of longevity as well as potential pitfalls and how to avoid them.

Messung der Lebensdauer in<em&gt; Drosophila melanogaster</em

Aging is a phenomenon that results in steady physiological deterioration in nearly all organisms in which it has been examined, leading to reduced ...

An Innovative Method for Exosome Quantification and Size Measurement

Although the biological importance of exosomes has recently gained an increasing amount of scientific and clinical attention, much is still unknown about their complex pathways, their bioavailability and their diverse functions in health and disease. Current work focuses on the presence and the behavior of exosomes (in vitro as well as in vivo) in the context of different human disorders, especially in the fields of oncology, gynecology and cardiology.
Unfortunately, neither a consensus regarding a gold standard for exosome isolation exists, nor is there an agreement on such a method for their quantitative analysis. As there are many methods for the purification of exosomes and also many possibilities for their quantitative and qualitative analysis, it is difficult to determine a combination of methods for the ideal approach. 
Here, we demonstrate nanoparticle tracking analysis (NTA), a semi-automated method for the characterization of exosomes after isolation from human plasma by ultracentrifugation. The presented results show that this approach for isolation, as well as the determination of the average number and size of exosomes, delivers reproducible and valid data, as confirmed by other methods, such as scanning electron microscopy (SEM).

A method for isolation of exosomes from whole blood and further analysis by nanoparticle tracking using a semi-automatic instrument is presented in this article. The presented technology provides an extremely sensitive method for visualizing and analyzing particles in liquid suspension.

Eine innovative Methode zur Quantifizierung und Exosom Size Measurement

Although the biological importance of exosomes has recently gained an increasing amount of scientific and clinical attention, much is still unknown about ...

Measurement of Metabolic Rate in Drosophila using Respirometry

Metabolic disorders are a frequent problem affecting human health. Therefore, understanding the mechanisms that regulate metabolism is a crucial scientific task. Many disease causing genes in humans have a fly homologue, making Drosophila a good model to study signaling pathways involved in the development of different disorders. Additionally, the tractability of Drosophila simplifies genetic screens to aid in identifying novel therapeutic targets that may regulate metabolism. In order to perform such a screen a simple and fast method to identify changes in the metabolic state of flies is necessary. In general, carbon dioxide production is a good indicator of substrate oxidation and energy expenditure providing information about metabolic state. In this protocol we introduce a simple method to measure CO2 output from flies. This technique can potentially aid in the identification of genetic perturbations affecting metabolic rate.

Measurement of Metabolic Rate in Drosophila using Respirometry

Metabolic disorders are among one of the most common diseases in humans. The genetically tractable model organism D. melanogaster can be used to identify novel genes that regulate metabolism. This paper describes a relatively simple method which allows studying the metabolic rate in flies by measuring their CO2 production.

Messung der Stoffwechselrate in<em&gt; Drosophila</em&gt; Mit Respirationstest

Metabolic disorders are a frequent problem affecting human health. Therefore, understanding the mechanisms that regulate metabolism is a crucial ...

Filtration Isolation of Nucleic Acids:  A Simple and Rapid DNA Extraction Method

FINA, filtration isolation of nucleic acids, is a novel extraction method which utilizes vertical filtration via a separation membrane and absorbent pad to extract cellular DNA from whole blood in less than 2 min. The blood specimen is treated with detergent, mixed briefly and applied by pipet to the separation membrane. The lysate wicks into the blotting pad due to capillary action, capturing the genomic DNA on the surface of the separation membrane. The extracted DNA is retained on the membrane during a simple wash step wherein PCR inhibitors are wicked into the absorbent blotting pad. The membrane containing the entrapped DNA is then added to the PCR reaction without further purification. This simple method does not require laboratory equipment and can be easily implemented with inexpensive laboratory supplies. Here we describe a protocol for highly sensitive detection and quantitation of HIV-1 proviral DNA from 100 &#181;l whole blood as a model for early infant diagnosis of HIV that could readily be adapted to other genetic targets.

We describe here a simple and rapid paper-based DNA extraction method of HIV proviral DNA from whole blood detected by quantitative PCR. This protocol can be extended for use in detecting other genetic markers or using alternative amplification methods.

Filtration Isolierung von Nukleinsäuren: Eine einfache und schnelle DNA-Extraktionsmethode

FINA, filtration isolation of nucleic acids, is a novel extraction method which utilizes vertical filtration via a separation membrane and absorbent pad ...