Vorrei ringraziare molto a David Carlson, professore di inglese presso Matsumoto Dental University, per il suo gentile supporto nella stesura di questo rapporto. Vorrei anche ringraziare Tadafumi Adachi, un seminarista nel nostro laboratorio, per la sua conformità come un soggetto in questa inchiesta.

1. Preparazione di elettrodi EMG <ol><li> Iniziate preparando nove elettrodi. Otto di essi sono utilizzati per la registrazione dei segnali dai siti sopra il muscolo, e uno è un elettrodo di riferimento. </li><li> Dopo aver collegato gli elettrodi di registrazione e di riferimento per l&#39;amplificatore, riempire i dischi con conduttanza elettrica-incolla. Ogni tipo è OK, ma un tipo di fluido a bassa è meglio. </li><li> Prima di collegare gli elettrodi alla pelle, sono il soggetto decisione verso il basso, e determinare la posizione approssimativa del muscolo massetere sul viso. </li><li> Il tendine superiore del muscolo massetere attribuisce al zigomatica, e il suo tendine inferiore all&#39;angolo della mandibola. </li><li> Posizionare gli elettrodi di registrazione otto su un lungo pezzo di nastro adesivo a pari distanza inter-elettrodica, e allegare l&#39;array alla superficie della pelle. L&#39;elettrodo prima registrazione è posto sulla dell&#39;arcata zigomatica, e l&#39;ultimo l&#39;angolo della mandibola. </li><li> Infine, collegare l&#39;elettrodo di riferimento alla punta del naso. </li></ol> 2. Registrazione EMG <ol><li> Per iniziare la registrazione, impostare i parametri del amplificatore multicanale analogico (MEG6100). Impostare il guadagno di x 500, il filtro passa-basso a 0,5 Hz, e il filtro passa alto a 10 kHz. </li><li> Collegare l&#39;otto uscite dell&#39;amplificatore analogico a un convertitore analogico-digitale (PCI-MIO-16E-4). Il segnale digitale viene elaborato con il software LabVIEW con una frequenza di campionamento di 20 kHz. </li><li> Quando tutto è collegato, EMG registrare durante rapido chewing-gum stringendo sul lato omolaterale. </li><li> Le tracce da otto canali vengono presentati sul display LabView subito dopo il processo di registrazione è stato completato. </li></ol> 3. EPP estrazione e l&#39;osservazione delle sue caratteristiche <ol><li> Per estrarre la componente PPE, prima rimuovere la componente potenziale d&#39;azione dal EMG grezzi, utilizzando un taglio alto filtro digitale (filtro Butterworth). </li><li> Cominciare ad applicare il filtro con una frequenza di taglio di 10 Hz. Un&#39;onda lenta che devia in direzione positiva o negativa dovrebbe apparire. Questa onda corrisponde al PPE, e la differenza di polarità riflette il lavandino-source relazione della corrente piastra terminale. </li><li> Durante la registrazione dal muscolo massetere, la flessione più negativa dell&#39;onda è prevista per la traccia dal sito di registrazione più inferiori, e la polarità dovrebbe spostare circa 3 siti di distanza da quel sito. </li><li> L&#39;entità della componente PPE può essere misurata come punto di picco della deviazione o una zona durante la flessione. </li><li> Il cambio di polarità del componente PPE può essere determinato tracciando l&#39;onda del PPE da ciascun canale contro un canale di riferimento che ha mostrato la flessione più negativi. </li><li> Ora, aumentando la frequenza di taglio, l&#39;onda lenta sarà oscillatorio. L&#39;oscillazione aumenta con l&#39;aumentare della frequenza di taglio e generalmente diventa evidente ad una frequenza di taglio di 30 Hz. </li><li> La fase dell&#39;onda invertirà tutta la traccia in cui la polarità dei 10Hz filtrata PPE onda ha mostrato una inversione. </li><li> Lo spostamento di fase dell&#39;oscillazione può essere controllato con i grafici stessi che sono stati applicati ai 10Hz-filtrata onda PPE. </li><li> Dal intervallo tra vicini picchi positivi e / o negativo di oscillazione, possiamo ottenere una approssimazione della frequenza di oscillazione </li></ol> 4. Registrazione EMG risultati <img src="/files/ftp_upload/1653/1653Fig1a.jpg" alt="Figura 1 a" /> Figura 1a: Qui viene mostrato uno schema degli otto siti lungo il muscolo massetere che sono state registrate da. <img src="/files/ftp_upload/1653/1653Fig1b.jpg" alt="Figura 1 b" /> Figura 1b: Vediamo un esempio di EMG monopolare registrate simultaneamente dai siti sopra il muscolo massetere in risposta al rapido stringendo gomma sul lato omolaterale. La componente PPE è stato estratto utilizzando un filtro high-cut digitale con una frequenza di taglio di 10Hz, che si sovrappongono prime EMG. In questo studio, la flessione più negativa è stata osservata in tracce-5 e -6 e la polarità cambiato attraverso traccia-3. <img src="/files/ftp_upload/1653/1653Fig1c.jpg" alt="Figura 1c" /> Figura 1c: Quando la frequenza di taglio del taglio alto filtro digitale è stata impostata su 30 Hz, l&#39;onda lenta esposte una oscillazione. La sua fase anche spostato attraverso traccia 3, in cui la polarità del 10Hz-filtrata PPE onda cambiato. L&#39;intervallo tra vicini picchi positivi della oscillazione è stata misurata. In questo soggetto, la media tra le picco intervallo era di 31,7 ± 6,5 msec più di 16 registrazioni.

<ol>
	<li>Eccles, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The physiology of synapses. , (1964).</li><li>Mitzdorf, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Current+source-density+method+and+application+in+cat+cerebral+cortex:+investigation+of+evoked+potentials+and+EEG+phenomena.">Current source-density method and application in cat cerebral cortex: investigation of evoked potentials and EEG phenomena.</a> Physiol. Rev. 65, 37-100 (1985).</li><li>Rall, W., Shepherd, G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Theoretical+reconstruction+of+field+potentials+and+dendrodendritic+synaptic+interactions+in+olfactory+bulb.">Theoretical reconstruction of field potentials and dendrodendritic synaptic interactions in olfactory bulb.</a> J. Neurophysiol. 31, 884-915 (1968).</li><li>Richardson, T. L., Turner, R. W., Miller, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Action-potential+discharge+in+hippocampal+CA1+pyramidal+neurons:+current+source+density+analysis.">Action-potential discharge in hippocampal CA1 pyramidal neurons: current source density analysis.</a> J. Neurophysiol. 58, 981-996 (1987).</li><li>Kumai, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Location+of+the+neuromuscular+junction+of+the+human+masseter+muscle+estimated+from+the+low+frequency+component+of+the+surface+electromyogram.">Location of the neuromuscular junction of the human masseter muscle estimated from the low frequency component of the surface electromyogram.</a> J. Jpn. Physiol. 55, 61-68 (2005).</li><li>Mito, K., Sakamoto, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Distribution+of+muscle+fiber+conduction+velocity+of+m.+masseter+during+voluntary+isometric+contraction.">Distribution of muscle fiber conduction velocity of m. masseter during voluntary isometric contraction.</a> Electroencephalogr. Clin. Neurophysiol. 40, 275-285 (2000).</li><li>Tokunaga, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two-dimensional+configuration+of+the+myoneural+junctions+of+human+masticatory+muscle+detected+with+matrix+electrode.">Two-dimensional configuration of the myoneural junctions of human masticatory muscle detected with matrix electrode.</a> J. Oral Rehabili. 25, 329-334 (1998).</li><li>Rohen, J. H., Yokochi, C., L&#x0171;tjen-Drecoll, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Color atlas of anatomy. , (2006).</li><li>Wichmann, T., DeLong, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Oscillation+in+the+basal+ganglia.">Oscillation in the basal ganglia.</a> Nature. 400, 621-622 (1999).</li></ol>

<ol><li> Come il potenziale negativo è considerata formata da un flusso di corrente di placca, e la flessione positiva, con il suo flusso-out [1,2,3,4], la traccia che mostra la flessione più negativo deve corrispondere al sito localizzare la giunzione neuromuscolare [5]. La figura 1b indica la giunzione neuromuscolare del muscolo massetere individuare nella sua parte inferiore, vicino all&#39;angolo della mandibola, che è circa la stessa di risultati ottenuti con un altro metodo che utilizza le modalità di conduzione del potenziale d&#39;a...

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		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
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<tr>
<td>Analogue filter</td>
<td>&nbsp;</td>
<td>Nihon Kohden</td>
<td>MEG6100</td>
<td>pre-,main-amplifier</td>
</tr>
<tr>
<td>A/D converter</td>
<td>&nbsp;</td>
<td>National Instruments</td>
<td>PCI-MIO-16E-4</td>
<td>PCI board for computer</td>
</tr>
<tr>
<td>Connection interface</td>
<td>&nbsp;</td>
<td>National Instruments</td>
<td>BNC-2090</td>
<td>8ch BNC adaptor</td>
</tr>
<tr>
<td>Disc electrodes</td>
<td>&nbsp;</td>
<td>Nihon Kohden</td>
<td>NS-11</td>
<td>Ag/AgCl (&Phi;8mm)</td>
</tr>
<tr>
<td>Electrode past</td>
<td>&nbsp;</td>
<td>Sanshin</td>
<td>SA-5</td>
<td>Semi-fluid carbon past</td>
</tr>
<tr>
<td>LabVIEW (Digital filter)</td>
<td>&nbsp;</td>
<td>National Instruments</td>
<td>V. 8.5</td>
<td>Programming language</td>
</tr>
<tr>
<td>Chewing gum</td>
<td>&nbsp;</td>
<td>Lotte</td>
<td>Green gum</td>
<td>Test food in clenching</td>
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extraction of the epp component from the surface emg

Un elettromiogramma di superficie (EMG), soprattutto quando ha registrato nei pressi della giunzione neuromuscolare, si prevede di contenere il potenziale di placca (EPP), componente che può essere estratto con un filtro segnale appropriato. Due fattori sono importanti: l&#39;EMG devono essere registrati in modo monopolare, e la registrazione deve essere fatto in modo che il segnale di bassa frequenza corrispondente del PPE non è eliminata. Questo rapporto spiega come estrarre la componente PPE dalla EMG del muscolo massetere in un soggetto umano. La superficie EMG viene registrato da otto siti che utilizzano elettrodi a disco tradizionali allineati lungo sopra il muscolo, con uguale distanza inter-elettrodo dal dell&#39;arcata zigomatica per l&#39;angolo della mandibola in risposta a stringere gomma veloce. Un elettrodo di riferimento è posto sulla punta del naso. La componente PPE viene estratto dal EMG prime applicando un taglio alto filtro digitale (2 ° dimensione filtro Butterworth) con una gamma di 10-35 Hz. Quando il filtro è impostato a 10 Hz, l&#39;estratto del PPE devia onda negativa o positiva a seconda del sito di registrazione. La differenza nella polarità riflette il lavandino-source relazione della corrente piastra finale, con il sito che mostra la flessione più negativo corrispondente alla giunzione neuromuscolare. Nel caso del muscolo massetere, la giunzione neuromuscolare è stimata essere situato nella parte inferiore vicino l&#39;angolo della mandibola. La componente PPE mostra una oscillazione interessante quando la frequenza di taglio del taglio alto filtro digitale è impostato a 30 Hz.. L&#39;oscillazione del PPE indica che la contrazione muscolare è regolata in modo intermittente. Tremori anormali che accompagnano vari tipi di malattie possono essere sostanzialmente a causa di questa oscillazione del PPE, che diventa più lento e difficile da interrompere.

Watch this Scientific Journal Video about Extraction of the EPP Component from the Surface EMG at JoVE.com

Extraction of the EPP Component from the Surface EMG

Il potenziale di placca (EPP) componente può essere estratto dalla superficie EMG utilizzando un filtro digitale. L&#39;estratto del PPE mostra oscillazione con una frequenza di circa 30 Hz.

Estrazione della componente PPE dalla superficie EMG

A surface electromyogram (EMG), especially when recorded near the neuromuscular junction, is expected to contain the endplate potential (EPP) component ...

extraction-of-the-epp-component-from-the-surface-emg

Research

JoVE Journal

Biology

12.5K Views.  Matsumoto Dental University. Il potenziale di placca (EPP) componente può essere estratto dalla superficie EMG utilizzando un filtro digitale. L'estratto del PPE mostra oscillazione con una frequenza di circa 30 Hz.

Video: Extraction of the EPP Component from the Surface EMG

Micro-dissection of Rat Brain for RNA or Protein Extraction from Specific Brain Region

Micro-dissection of rat brain into various regions is extremely important for the study of different neurodegenerative diseases. This video demonstrates micro-dissection of four major brain regions include olfactory bulb, frontal cortex, striatum and hippocampus in fresh rat brain tissue. Useful tips for quick removal of respective regions to avoid RNA and protein degradation of the tissue are given.

Micro-dissection of rat brain into various regions is extremely important for the study of different neurodegenerative diseases. This video demonstrates micro-dissection of four major brain regions include olfactory bulb, frontal cortex, striatum and hippocampus in fresh rat brain tissue. Useful tips for quick removal of respective regions to avoid RNA and protein degradation of the tissue are given.

Micro-dissezione del cervello di ratto per estrazione RNA o proteine ​​da Regione specifiche del cervello

Micro-dissection of rat brain into various regions is extremely important for the study of different neurodegenerative diseases. This video demonstrates ...

Ricerca

Biologia

RNA Extraction from Neuroprecursor Cells Using the Bio-Rad Total RNA Kit

Estrazione RNA da cellule Neuroprecursor Utilizzando il Bio-Rad RNA totale Kit

Retrograde Labeling of Retinal Ganglion Cells by Application of Fluoro-Gold on the Surface of Superior Colliculus

Retinal ganglion cell (RGC) counting is essential to evaluate retinal degeneration especially in glaucoma. Reliable RGC labeling is fundamental for evaluating the effects of any treatment. In rat, about 98% of RGCs is known to project to the contralateral superior colliculus (SC) (Forrester and Peters, 1967). Applying fluoro-gold (FG) on the surface of SC can label almost all the RGCs, so that we can focus on this most vulnerable retinal neuron in glaucoma. FG is taken up by the axon terminals of retinal ganglion cells and bilaterally transported retrogradely to its somas in the retina. Compare with retrograde labeling of RGC by putting FG at stump of transected optic nerve for 2 days, the interference of RGC survival is minimized. Compare with cresyl violet staining that stains RGCs, amacrine cells and endothelium of the blood vessel in the retinal ganglion cell layer, this labeling method is more specific to the RGC. This video describes the method of retrograde labeling of RGC by applying FG on the surface of SC. The surgical procedures include drilling the skull; aspirating the cortex to expose the SC and applying gelatin sponge over entire dorsal surface of SC are shown. Useful tips for avoiding massive intracranial bleeding and aspiration of the SC have been given.

This video describes the method of retrograde labeling of RGC by applying fluoro-gold (FG) on the surface of superior colliculus (SC). Technique involves drilling the skull, aspirating the cortex, and applying gelatin sponge over entire dorsal surface of SC.

Etichettatura retrograda di cellule gangliari della retina mediante l&#39;applicazione di fluoro-oro sulla superficie del collicolo superiore

Retinal ganglion cell (RGC) counting is essential to evaluate retinal degeneration especially in glaucoma. Reliable RGC labeling is fundamental for ...

Avidity-based Extracellular Interaction Screening (AVEXIS) for the Scalable Detection of Low-affinity Extracellular Receptor-Ligand Interactions

Extracellular protein:protein interactions between secreted or membrane-tethered proteins are critical for both initiating intercellular communication and ensuring cohesion within multicellular organisms. Proteins predicted to form extracellular interactions are encoded by approximately a quarter of human genes1, but despite their importance and abundance, the majority of these proteins have no documented binding partner. Primarily, this is due to their biochemical intractability: membrane-embedded proteins are difficult to solubilise in their native conformation and contain structurally-important posttranslational modifications. Also, the interaction affinities between receptor proteins are often characterised by extremely low interaction strengths (half-lives &lt; 1 second) precluding their detection with many commonly-used high throughput methods2. 
Here, we describe an assay, AVEXIS (AVidity-based EXtracellular Interaction Screen) that overcomes these technical challenges enabling the detection of very weak protein interactions (t1/2 &le; 0.1 sec) with a low false positive rate3. The assay is usually implemented in a high throughput format to enable the systematic screening of many thousands of interactions in a convenient microtitre plate format (Fig. 1). It relies on the production of soluble recombinant protein libraries that contain the ectodomain fragments of cell surface receptors or secreted proteins within which to screen for interactions; therefore, this approach is suitable for type I, type II, GPI-linked cell surface receptors and secreted proteins but not for multipass membrane proteins such as ion channels or transporters.
The recombinant protein libraries are produced using a convenient and high-level mammalian expression system4, to ensure that important posttranslational modifications such as glycosylation and disulphide bonds are added. Expressed recombinant proteins are secreted into the medium and produced in two forms: a biotinylated bait which can be captured on a streptavidin-coated solid phase suitable for screening, and a pentamerised enzyme-tagged (&beta;-lactamase) prey. The bait and prey proteins are presented to each other in a binary fashion to detect direct interactions between them, similar to a conventional ELISA (Fig. 1). The pentamerisation of the proteins in the prey is achieved through a peptide sequence from the cartilage oligomeric matrix protein (COMP) and increases the local concentration of the ectodomains thereby providing significant avidity gains to enable even very transient interactions to be detected. By normalising the activities of both the bait and prey to predetermined levels prior to screening, we have shown that interactions having monomeric half-lives of 0.1 sec can be detected with low false positive rates3.

Avidity-based Extracellular Interaction Screening AVEXIS for the Scalable Detection of Low-affinity Extracellular Receptor-Ligand Interactions

AVEXIS is a high throughput protein interaction assay developed to systematically screen for novel extracellular receptor-ligand pairs involved in cellular recognition processes. It is specifically designed to detect transient protein interactions that are difficult to identify using other high throughput approaches.

Avidità-based Screening Interaction extracellulare (AVEXIS) per il rilevamento scalabile di bassa affinità extracellulare del recettore-ligando interazioni

Extracellular protein:protein interactions between secreted or membrane-tethered proteins are critical for both initiating intercellular communication and ...

Budding Yeast Protein Extraction and Purification for the Study of Function, Interactions, and Post-translational Modifications

Homogenization by bead beating is a fast and efficient way to release DNA, RNA, proteins, and metabolites from budding yeast cells, which are notoriously hard to disrupt. Here we describe the use of a bead mill homogenizer for the extraction of proteins into buffers optimized to maintain the functions, interactions and post-translational modifications of proteins. Logarithmically growing cells expressing the protein of interest are grown in a liquid growth media of choice. The growth media may be supplemented with reagents to induce protein expression from inducible promoters (e.g. galactose), synchronize cell cycle stage (e.g. nocodazole), or inhibit proteasome function (e.g. MG132). Cells are then pelleted and resuspended in a suitable buffer containing protease and/or phosphatase inhibitors and are either processed immediately or frozen in liquid nitrogen for later use. Homogenization is accomplished by six cycles of 20 sec&#160;bead-beating (5.5 m/sec), each followed by one minute incubation on ice. The resulting homogenate is cleared by centrifugation and small particulates can be removed by filtration. The resulting cleared whole cell extract (WCE) is precipitated using 20% TCA for direct analysis of total proteins by SDS-PAGE followed by Western blotting. Extracts are also suitable for affinity purification of specific proteins, the detection of post-translational modifications, or the analysis of co-purifying proteins. As is the case for most protein purification protocols, some enzymes and proteins may require unique conditions or buffer compositions for their purification and others may be unstable or insoluble under the conditions stated. In the latter case, the protocol presented may provide a useful starting point to empirically determine the best bead-beating strategy for protein extraction and purification. We show the extraction and purification of an epitope-tagged SUMO E3 ligase, Siz1, a cell cycle regulated protein that becomes both sumoylated and phosphorylated, as well as a SUMO-targeted ubiquitin ligase subunit, Slx5.

The preparation of high quality yeast cell extracts is a necessary first step in the analysis of individual proteins or entire proteomes. Here we describe a fast, efficient, and reliable homogenization protocol for budding yeast cells that has been optimized to preserve protein functions, interactions, and post-translational modifications.

Germogliamento lievito proteine ​​estrazione e purificazione per lo Studio della funzione, interazioni e modificazioni post-traduzionali

Homogenization by bead beating is a fast and efficient way to release DNA, RNA, proteins, and metabolites from budding yeast cells, which are notoriously ...

Real Time Measurements of Membrane Protein:Receptor Interactions Using Surface Plasmon Resonance (SPR)

Protein-protein interactions are pivotal to most, if not all, physiological processes, and understanding the nature of such interactions is a central step in biological research. Surface Plasmon Resonance (SPR) is a sensitive detection technique for label-free study of bio-molecular interactions in real time. In a typical SPR experiment, one component (usually a protein, termed 'ligand') is immobilized onto a sensor chip surface, while the other (the 'analyte') is free in solution and is injected over the surface. Association and dissociation of the analyte from the ligand are measured and plotted in real time on a graph called a sensogram, from which pre-equilibrium and equilibrium data is derived. Being label-free, consuming low amounts of material, and providing pre-equilibrium kinetic data, often makes SPR the method of choice when studying dynamics of protein interactions. However, one has to keep in mind that due to the method's high sensitivity, the data obtained needs to be carefully analyzed, and supported by other biochemical methods. 
SPR is particularly suitable for studying membrane proteins since it consumes small amounts of purified material, and is compatible with lipids and detergents. This protocol describes an SPR experiment characterizing the kinetic properties of the interaction between a membrane protein (an ABC transporter) and a soluble protein (the transporter's cognate substrate binding protein).

Real Time Measurements of Membrane Protein:Receptor Interactions Using Surface Plasmon Resonance SPR

Surface Plasmon Resonance (SPR) is a label-free method for detecting bio-molecular interactions in real time. Herein, a protocol for a membrane protein:receptor interaction experiment is described, while discussing the pros and cons of the technique.

Le misurazioni in tempo reale delle Membrane Protein: recettore interazioni Uso risonanza plasmonica di superficie (SPR)

Protein-protein interactions are pivotal to most, if not all, physiological processes, and  understanding the nature of such interactions is a central ...

The Infiltration-centrifugation Technique for Extraction of Apoplastic Fluid from Plant Leaves Using Phaseolus vulgaris as an Example

The apoplast is a distinct extracellular compartment in plant tissues that lies outside the plasma membrane and includes the cell wall. The apoplastic compartment of plant leaves is the site of several important biological processes, including cell wall formation, cellular nutrient and water uptake and export, plant-endophyte interactions and defence responses to pathogens. The infiltration-centrifugation method is well established as a robust technique for the analysis of the soluble apoplast composition of various plant species. The fluid obtained by this method is commonly known as apoplast washing fluid (AWF). The following protocol describes an optimized vacuum infiltration and centrifugation method for AWF extraction from Phaseolus vulgaris (French bean) cv. Tendergreen leaves. The limitations of this method and the optimization of the protocol for other plant species are discussed. Recovered AWF can be used in a wide range of downstream experiments that seek to characterize the composition of the apoplast and how it varies in response to plant species and genotype, plant development and environmental conditions, or to determine how microorganisms grow in apoplast fluid and respond to changes in its composition.

The Infiltration-centrifugation Technique for Extraction of Apoplastic Fluid from Plant Leaves Using Phaseolus vulgaris as an Example

This protocol details the optimized extraction of apoplast washing fluid from plant leaves, using French bean plants (Phaseolus vulgaris) as a model example.

La tecnica infiltrazione-centrifugazione per l&#39;estrazione di apoplastico fluido da foglie delle piante Utilizzo<em&gt; Phaseolus vulgaris</em&gt; Come un esempio

The apoplast is a distinct extracellular compartment in plant tissues that lies outside the plasma membrane and includes the cell wall. The apoplastic ...

Real-time Imaging of Plant Cell Surface Dynamics with Variable-angle Epifluorescence Microscopy

A plant&#8217;s cell surface is its interface for perceiving environmental cues; it responds with cell biological changes such as membrane trafficking and cytoskeletal rearrangement. Real-time and high-resolution image analysis of such intracellular events will increase the understanding of plant cell biology at the molecular level. Variable angle epifluorescence microscopy (VAEM) is an emerging technique that provides high-quality, time-lapse images of fluorescently-labeled proteins on the plant cell surface. In this article, practical procedures are described for VAEM specimen preparation, adjustment of the VAEM optical system, movie capturing and image analysis. As an example of VAEM observation, representative results are presented on the dynamics of PATROL1. This is a protein essential for stomatal movement, thought to be involved in proton pump delivery to plasma membranes in the stomatal complex of Arabidopsis thaliana. VAEM real-time observation of guard cells and subsidiary cells in A. thaliana cotyledons showed that fluorescently-tagged PATROL1 appeared as dot-like structures on plasma membranes for several seconds and then disappeared. Kymograph analysis of VAEM movie data determined the time distribution of the presence (termed &#8216;residence time&#8217;) of the dot-like structures. The use of VAEM is discussed in the context of this example.

The goal of this protocol is to demonstrate how to monitor fluorescently-tagged protein dynamics on plant cell surfaces with variable-angle epifluorescence microscopy, showing blinking dots of GFP-tagged PATROL1, a membrane trafficking protein, in the cell cortex of the stomatal complex in Arabidopsis thaliana.

In tempo reale Imaging di Pianta Dynamics cellulare con superficie variabile angolo epifluorescenza Microscopia

A plant&#8217;s cell surface is its interface for perceiving environmental cues; it responds with cell biological changes such as membrane trafficking and ...

Methods for the Extraction of Endosymbionts from the Whitefly Bemisia tabaci

Bacterial symbionts form an intimate relationship with their hosts and confer advantages to the hosts in most cases. Genomic information is critical to study the functions and evolution of bacterial symbionts in their host. As most symbionts cannot be cultured in vitro, methods to isolate an adequate quantity of bacteria for genome sequencing are very important. In the whitefly Bemisia tabaci, a number of endosymbionts have been identified and are predicted to be of importance in the development and reproduction of the pests through multiple approaches. However, the mechanism underpinning the associations remains largely unknown. The obstacle partially comes from the fact that the endosymbionts in whitefly, mostly restrained in bacteriocytes, are hard to separate from the host cells. Here we report a step-by-step protocol for the identification, extraction and purification of endosymbionts from the whitefly B. tabaci mainly by dissection and filtration. Endosymbiont samples prepared by this method, although still a mixture of different endosymbiont species, are suitable for subsequent genome sequencing and analysis of the possible roles of endosymbionts in B. tabaci. This method may also be used to isolate endosymbionts from other insects.

Methods for the Extraction of Endosymbionts from the Whitefly Bemisia tabaci

Here, we present a protocol to isolate endosymbionts from the whitefly Bemisia tabaci through dissection and filtration. After amplification, the DNA samples are suitable for subsequent sequencing and study of the mutualism between endosymbionts and whitefly.

Metodi per l&#39;estrazione di Endosymbionts dalla Whitefly<em&gt; Bemisia tabaci</em

Bacterial symbionts form an intimate relationship with their hosts and confer advantages to the hosts in most cases. Genomic information is critical to ...

In Vivo Surface Electrocardiography for Adult Zebrafish

The electrocardiogram waveforms of adult zebrafish and those of humans are remarkably similar. These electrocardiogram similarities enhance the value of zebrafish not only as a research model for human cardiac electrophysiology and myopathies but also as a surrogate model in high throughput pharmaceutical screening for potential cardiotoxicities to humans, such as QT prolongation. As such, in vivo electrocardiography for adult zebrafish is an electrical phenotyping tool that is necessary, if not indispensable, for cross-sectional or longitudinal in vivo electrophysiological characterizations. However, too often, the lack of a reliable, practical, and cost-effective recording method remains a major challenge preventing this in vivo diagnostic tool from becoming more readily accessible. Here, we describe a practical, straightforward approach to in vivo electrocardiography for adult zebrafish using a low-maintenance, cost-effective, and comprehensive system that yields consistent, reliable recordings. We illustrate our protocol using healthy adult male zebrafish of 12-18 months of age. We also introduce a rapid real-time interpretation strategy for quality validation to ensure data accuracy and robustness early in the electrocardiogram recording process.

Here, we present a reliable, minimally invasive, and cost-effective method to record and interpret electrocardiograms in live anesthetized adult zebrafish.

Elettrocarcardio in superficie in vivo per il pesce zebra adulto

The electrocardiogram waveforms of adult zebrafish and those of humans are remarkably similar. These electrocardiogram similarities enhance the value of ...