Questo lavoro è stato sostenuto dal National Institutes of Health concede F32 NS078958 (DTB) e R01 AG033620 (BG).

1. Montare Tester Volo <ol><li> Cilindro volo sicuro a Ring stand 1 con fascette catena. (Lasciare circa 3 cm sotto il cilindro per pesare piatto.) (Nota: Il cilindro volo che usiamo è lungo 90 centimetri con un diametro di 13,5 centimetri.) </li><li> Inserire pesare piatto con un sottile strato di olio minerale sotto il cilindro volo. </li><li> Imbuto sicuro a Ring stand 2 utilizzando una pinza anello e morsetto artiglio. Regolare l&#39;altezza dell&#39;imbuto modo che il fondo dell&#39;imbuto è a filo con la parte superiore del cilindro volo. (Nota: il diametro della punta dell&#39;imbuto deve essere inferiore al diametro esterno di flaconi posizionati nei tubi goccia in modo che le fiale non cadere.) </li><li> Inserire il tubo discesa nella parte superiore dell&#39;imbuto e fissarlo con un morsetto artiglio. (Nota: Usiamo un tubo goccia che è lungo 25 centimetri Dropping vola contenenti flaconi da questa altezza permette di espulsione coerente di tutte le mosche con forza uniforme Il diametro interno del tubo di caduta deve essere sligh..temente maggiore del diametro esterno del flaconcino per consentire il flaconcino di cadere liberamente.) </li><li> Tagliare foglio di poliacrilammide (s) per la dimensione corretta. (Nota: Per facilitare l&#39;inserimento e la rimozione del foglio, la larghezza deve essere leggermente inferiore alla circonferenza interna del cilindro volo). </li><li> Applicare uno strato sottile di Tangle-Trap al foglio. Lasciare riposare per 1 ora prima dell&#39;uso. (Nota: Lasciare spazio sufficiente nella parte superiore e inferiore del foglio (circa 3 cm) rivestito di cogliere il foglio per l&#39;inserimento / rimozione.) </li><li> Inserire il foglio poliacrilammide nel cilindro volo. </li><li> Montare la pista fotocamera utilizzando staffe di supporto di pino. (Nota: assicurarsi che il fondo della pista può supportare la fotocamera senza bloccare la lente Fare riferimento alla Figura 1B..) </li><li> Aggiungi tappi e avvitare. (Nota: posto i tappi nelle posizioni che permetteranno la telecamera per visualizzare l&#39;intero foglio di plastica in modalità panoramica.) </li></ol> 2. Eseguire Experiment <ol> &lt;li&gt; Raccogliere le fiale di mosche da testare. Per ottenere i migliori risultati, utilizzare non più di 20 mosche / flacone. </li><li> Toccare delicatamente le mosche al fondo della fiala, scollegare, quindi inserire nel tubo goccia e rilasciare fiala. (Nota: Il flaconcino cade il tubo calo fino a raggiungere l&#39;apertura stretto imbuto Quando il flaconcino colpisce l&#39;imbuto, le mosche vengono espulsi nel cilindro di volo.). </li><li> Sollevare il tubo di caduta per rimuovere la fiala vuota. (Nota: più fiale di mosche dello stesso gruppo di prova possono essere analizzati su un singolo foglio di poliacrilammide Troviamo che fino a 200 mosche (10 flaconcini da 20 mosche ciascuno) possono essere testati e ripreso prontamente su un unico foglio.. </li><li> Togliere il foglio di plastica e posizionarlo su una superficie piatta e bianca. (Nota: cartoncino bianco può essere utilizzato se top panchina sono di colore scuro.) </li><li> Montare la pista fotocamera sul foglio di plastica. La telecamera deve essere sufficientemente alto sopra il foglio di avere sia la parte superiore e inferiore del foglio nel campo visivo. </li><li> Far scorrere la fotocamera lungo °e traccia tenendo premuto il pulsante &quot;cattura&quot; per acquisire un&#39;immagine panoramica. </li><li> Il numero di mosche atterraggio nell&#39;olio può essere conteggiato manualmente per ogni prova. </li><li> Ripetere i passaggi 2,2-2,7 per tutte le condizioni di un dato esperimento. Le mosche possono essere rimossi dal foglio tra ogni prova. In alternativa, possono essere utilizzati diversi fogli, con un nuovo foglio per ogni prova. </li></ol> 3. Raccolta dati <ol><li> Apri file di immagine utilizzando il software ImageJ. </li><li> Ritagliare le immagini se necessario, per includere solo la superficie di atterraggio. (Questa è l&#39;area rivestita in Tangle-Trap.) </li><li> Converti immagini a 8-bit in scala di grigi. </li><li> Creare una &quot;soglia&quot; per filtrare il fondo bianco. (Immagine → Regola → Threshold). </li><li> Impostare i parametri per identificare ogni volo usando il menu &quot;analizzare le particelle&quot;. (Analizza → Analizza Particles) Definire i parametri utilizzati per identificare una particella. Con il nostro set up, troviamo che l&#39;utilizzo di unarea di 5-90 pixel 2 e una circolarità di 0,4-1,0 identifichi accuratamente tutti i campioni. </li><li> Misurare la posizione di ogni volo usando l&#39;elenco generato delle coordinate per ogni particella. La coordinata x in pixel possono essere convertiti in centimetri per calcolare l&#39;altezza di atterraggio. </li><li> Importare tabella in un foglio di calcolo (come 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>

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Usando i metodi qui descritti, siamo stati in grado di valutare rapidamente le prestazioni di volo di un gran numero di mutanti di Drosophila, fornendo una maggiore efficienza rispetto al passato. Per i nostri esperimenti, abbiamo abitualmente separati maschi e femmine e li alleviamo a bassa densità (meno di 20 mosche / fiala) per limitare l&#39;aggressività che potrebbero danneggiare le ali. Un&#39;altra considerazione importante è quello di controllare adeguatamente le differenze nelle prestazioni di volo ...

Drosophila è stato a lungo utilizzato per studiare le basi genetiche del comportamento 1, ed i ricercatori hanno messo a punto una serie di modi per analizzare i vari tipi di comportamento 2-6. Le mosche sono stati particolarmente utili per fornire utili modelli di malattie neuromuscolari 7. Un test comunemente usato per studiare il comportamento locomotore è la prestazione di volo. Il tester volo originale è utile per identificare ponti mutanti difettosi e per la valutazione quantitativa della capacità di volo 1, ma ha diversi difetti che ne limitano l&#39;applicazione per schermi ad alto rendimento: l&#39;uso di bombole rivestite petrolio è disordinato e ingombrante, alcune funzionalità come la lunghezza del cilindro e l&#39;introduzione di mosche nel tubo con forza variabile ridurre la precisione quantitativa, ed è difficile da recuperare in linea diretta dal tester. Per superare queste limitazioni, abbiamo modificato il tester volo per includere una serie di miglioramenti. Abbiamo aggiunto una &quot;goccia tuessere &quot;introdurre linea per eliminare variabilità tra esperimenti e utenti. Usiamo lastre acriliche rimovibili rivestiti con un adesivo che consente una più facile pulizia e recupero di singoli mosche. Abbiamo aumentato la lunghezza del tubo di volo per migliorare la precisione e l&#39;affidabilità quantitativa. Infine , si usa una fotocamera digitale e software di imaging per calcolare le altezze sbarco di mosche. Crediamo che questi miglioramenti saranno utili a qualsiasi laboratorio interessato a condurre schermi genetici su larga scala per i difetti di prestazioni di volo.

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			<td height="33" style="height:33px;width:216px;">Putty knife</td>
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			<td><a href="http://www.homedepot.com">www.homedepot.com</a></td>
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			<td height="33" style="height:33px;width:216px;">Tangle Trap Insect Trap Coating</td>
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			<td style="width:132px;">268941</td>
			<td><a href="http://www.biconet.com">www.biconet.com</a></td>
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			<td height="33" style="height:33px;width:216px;">mineral oil</td>
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			<td height="33" style="height:33px;width:216px;">white poster board</td>
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			<td height="33" style="height:33px;width:216px;">ImageJ Software</td>
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			<td>http://rsb.info.nih.gov/ij/</td>
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			<td height="33" style="height:33px;width:216px;">digital camera</td>
			<td style="width:171px;">Sony</td>
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			<td height="33" style="height:33px;width:216px;">fine forceps</td>
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			<td><a href="http://www.finescience.com">www.finescience.com</a></td>
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			<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>
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			<td height="33" style="height:33px;width:216px;">flight cylinder (acrylic)</td>
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			<td style="width:132px;">8486K943</td>
			<td><a href="http://www.mcmaster.com">www.mcmaster.com</a></td>
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			<td height="33" style="height:33px;width:216px;">polycarbonate sheets</td>
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			<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>
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			<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>
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			<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>
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			<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>
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			<td height="33" style="height:33px;width:216px;">chain clamps (x2)</td>
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			<td style="width:132px;">21573-275</td>
			<td><a href="http://www.vwr.com">www.vwr.com</a></td>
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		<tr height="33">
			<td height="33" style="height:33px;width:216px;">glass vials</td>
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			<td style="width:132px;">66020-198</td>
			<td><a href="http://www.vwr.com/">www.vwr.com</a></td>
		</tr>
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an improved method for accurate and rapid measurement of flight performance in drosophila

Drosophila ha dimostrato di essere un sistema modello utile per l&#39;analisi del comportamento, comprensivo di volo. Il tester volo caduta coinvolta iniziale vola in un rivestimento d&#39;olio cilindro graduato, altezza atterraggio fornito una misura della performance di volo da valutare come mosche lontane cadranno prima di produrre abbastanza spinta a mettersi in contatto con la parete del cilindro. Qui si descrive una versione aggiornata del tester volo con quattro importanti miglioramenti. In primo luogo, abbiamo aggiunto un &quot;tubo pescante&quot; per garantire che tutte le mosche entrano nel cilindro volo ad una velocità simile tra la prova, eliminando la variabilità tra gli utenti. In secondo luogo, abbiamo sostituito il rivestimento dell&#39;olio con teli di plastica estraibili rivestiti in Tangle-Trap, un adesivo progettato per catturare insetti vivi. In terzo luogo, usiamo un cilindro più lungo per consentire la discriminazione più accurata capacità di volo. Quarto si usa una fotocamera digitale e software di imaging per automatizzare il punteggio delle prestazioni di volo. Questi miglioramenti consentono il rapid, la valutazione quantitativa del comportamento in volo, utile per grandi dataset e schermi genetici su larga scala.

<html> La figura 1A mostra uno schema del gruppo di tester volo aggiornato. Figura 1B illustra il disegno tracciato permette alla fotocamera di scattare un&#39;immagine panoramica senza bloccare il campo visivo. Risultati rappresentativi sono mostrati nella Figura 2, in cui le prestazioni di volo di mosche mutanti slowpoke, che hanno un volo noto difetto 8-10, vengono confrontati con wild-type Canton-S mosche. Controllo vola costantemente att...

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

Qui si descrive un metodo per la misurazione rapida e accurata delle prestazioni di volo in Drosophila, consentendo di screening high-throughput.

Un metodo migliore per precisa e rapida misurazione delle performance in volo<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 ...

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Research

JoVE Journal

Biology

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

11.6K Views.  University of Wisconsin-Madison.  Qui si descrive un metodo per la misurazione rapida e accurata delle prestazioni di volo in Drosophila, consentendo di screening high-throughput. 

Video: 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.

Pirosequenziamento: un metodo semplice per genotipizzazione accurata

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

Ricerca

Biologia

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.

Ad alta risoluzione misurazione del comportamento Odor-Driven in Larve Drosophila

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.

Un sistema magnetico Tether per Indagare visivo e olfattivo di controllo mediata Volo 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. ...

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.

Visivamente monitoraggio Odore mediata durante il volo 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.

Un metodo migliorato di isolamento dell&#39;RNA da Pino Loblolly ( P. taeda L.) e altre specie di conifere

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.

Endurance Training protocollo e saggi prestazioni longitudinali per 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.

Misura della durata della vita 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.

Un metodo innovativo per Exosome quantificazione e 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.

Misurazione del tasso metabolico in<em&gt; Drosophila</em&gt; Utilizzando respirometria

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.

L&#39;isolamento di filtrazione di acidi nucleici: DNA metodo di estrazione semplice e veloce

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