Name: rapid isolation and purification of mitochondria for transplantation by tissue dissociation and differential filtration
Uploaded: 2014-09-06T14:00:00
Description: Watch this Scientific Journal Video about Rapid Isolation And Purification Of Mitochondria For Transplantation By Tissue Dissociation And Differential Filtration at JoVE.com

This study was supported by National Heart, Lung, and Blood Institute Grant HL- 103542, and The BCH Anesthesia Research Foundation&#8217;s Distinguished Trailblazer Award to CAP.

Preparation
<ol>
	<li>Prepare 1 M K-HEPES Stock Solution (adjust pH to 7.2 with KOH).</li>
	<li>Prepare 0.5 M K-EGTA Stock Solution (adjust pH to 8.0 with KOH).</li>
	<li>Prepare 1 M KH2PO4 Stock Solution.</li>
	<li>Prepare 1 M MgCl2 Stock Solution.</li>
	<li>Prepare Homogenizing Buffer (pH 7.2) 300 mM sucrose, 10 mM K-HEPES, and 1 mM K-EGTA. Store at 4 &#176;C.</li>
	<li>Prepare Respiration Buffer 250 mM sucrose, 2 mM KH2PO4, 10 mM MgCl2, 20 mM K-HEPES ...

<ol>
	<li>van Loo, G., Saelens, X., van Gurp, M., MacFarlane, M., Martin, S. J., Vandenabeele, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+mitochondrial+factors+in+apoptosis:+a+Russian+roulette+with+more+than+one+bullet.">The role of mitochondrial factors in apoptosis: a Russian roulette with more than one bullet.</a> Cell Death Differ. 9 (10), 1031-1042 (2002).</li><li>Szabadkai, G., Duchen, 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=Mitochondria:+the+hub+of+cellular+Ca2++signaling.">Mitochondria: the hub of cellular Ca2+ signaling.</a> Physiology (Bethesda). 23, 84-94 (2008).</li><li>Chan, D. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mitochondria:+Dynamic+Organelles+in+Disease,+Aging,+and+Development.">Mitochondria: Dynamic Organelles in Disease, Aging, and Development.</a> Cell. 125 (7), 1241-1252 (2006).</li><li>Picard, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mitochondrial+structure+and+function+are+disrupted+by+standard+Isolation+methods.">Mitochondrial structure and function are disrupted by standard Isolation methods.</a> PLoS ONE. 6 (3), e18317 (2011).</li><li>Bensley, R. R., Hoerr, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Studies+on+cell+structure+by+freeze-drying+method;+preparation+and+properties+of+mitochondria.">Studies on cell structure by freeze-drying method; preparation and properties of mitochondria.</a> Anat Rec. 60, 449-455 (1934).</li><li>Claude, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fractionation+of+mammalian+liver+cells+by+differential+centrifugation+II.+Experimental+procedures+and+results.">Fractionation of mammalian liver cells by differential centrifugation II. Experimental procedures and results.</a> J Exp Med. 84 (1), 61-89 (1946).</li><li>Hogeboom, H., Schneider, W. C., Palade, G. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cytochemical+studies+of+mammalian+tissues;+isolation+of+intact+mitochondria+from+rat+liver;+some+biochemical+properties+of+mitochondria+and+submicroscopic+particulate+material.">Cytochemical studies of mammalian tissues; isolation of intact mitochondria from rat liver; some biochemical properties of mitochondria and submicroscopic particulate material.</a> J Biol Chem. 172 (2), 619-635 (1948).</li><li>Ernster, L., Schtaz, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mitochondria:+a+historical+Review.">Mitochondria: a historical Review.</a> J Cell Biol. 91 (3 Pt 2), 227s-255s (1981).</li><li>Pallotti, F., Lenaz, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+and+subfractionation+of+mitochondria+from+animal+cells+and+tissue+culture+lines.">Isolation and subfractionation of mitochondria from animal cells and tissue culture lines.</a> Methods Cell Biol. 80, 3-44 (2007).</li><li>Schmitt, 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=A+semi-automated+method+for+isolating+functionally+intact+mitochondria+from+cultured+cells+and+tissue+biopsies.">A semi-automated method for isolating functionally intact mitochondria from cultured cells and tissue biopsies.</a> Anal Biochem. 443 (1), 66-74 (2013).</li><li>Fern&#225;ndez-Vizarra, E., Ferr&#237;n, G., P&#233;rez-Martos, A., Fern&#225;ndez-Silva, P., Zeviani, M., Enr&#237;quez, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+of+mitochondria+for+biogenetical+studies:+An+update.">Isolation of mitochondria for biogenetical studies: An update.</a> Mitochondrion. 10 (3), 253-262 (2010).</li><li>Graham, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chapter+3,+Unit+3.3,+Isolation+of+mitochondria+from+tissues+and+cells+by+differential+centrifugation.">Chapter 3, Unit 3.3, Isolation of mitochondria from tissues and cells by differential centrifugation.</a> Curr Protoc Cell Biol. , (2001).</li><li>Frezza, C., Cipolat, S., Scorrano, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Organelle+isolation:+functional+mitochondria+from+mouse+liver,+muscle+and+cultured+fibroblasts.">Organelle isolation: functional mitochondria from mouse liver, muscle and cultured fibroblasts.</a> Nat Protoc. 2 (2), 287-295 (2007).</li><li>Wieckowski, M. R., Giorgi, C., Lebiedzinska, M., Duszynski, J., Pinton, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+of+mitochondria-associated+membranes+and+mitochondria+from+animal+tissues+and+cells.">Isolation of mitochondria-associated membranes and mitochondria from animal tissues and cells.</a> Nat Protoc. 4 (11), 1582-1590 (2009).</li><li>Gostimskaya, I., Galkin, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+of+highly+coupled+rat+heart+mitochondria.">Preparation of highly coupled rat heart mitochondria.</a> J Vis Exp. (43), (2010).</li><li>Gross, V. 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=Isolation+of+functional+mitochondria+from+rat+kidney+and+skeletal+muscle+without+manual+homogenization.">Isolation of functional mitochondria from rat kidney and skeletal muscle without manual homogenization.</a> Anal Biochem. 418 (2), 213-223 (2011).</li><li>Masuzawa, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transplantation+of+autologously+derived+mitochondria+protects+the+heart+from+ischemia-reperfusion+injury.">Transplantation of autologously derived mitochondria protects the heart from ischemia-reperfusion injury.</a> American J Physiol Heart and Circ Physiol. 304 (7), (2013).</li><li>McCully, J. D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Injection+of+isolated+mitochondria+during+early+reperfusion+for+cardioprotection.">Injection of isolated mitochondria during early reperfusion for cardioprotection.</a> American J Physiol Heart and Circ Physiol. 296 (1), 94-105 (2009).</li><li>Olson, M. S., Von Korff, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Changes+in+endogenous+substrates+of+isolated+rabbit+heart+mitochondria+during+storage.">Changes in endogenous substrates of isolated rabbit heart mitochondria during storage.</a> J Biol Chem. 242 (2), 325-332 (1967).</li><li>Diepart, C., 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=Comparison+of+methods+for+measuring+oxygen+consumption+in+tumor+cells+in+vitro.">Comparison of methods for measuring oxygen consumption in tumor cells in vitro.</a> Anal Biochem. 396 (2), 250-256 (2010).</li><li>Lanza, I. R., Nair, K. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+assessment+of+isolated+mitochondria+in+vitro.">Functional assessment of isolated mitochondria in vitro.</a> Methods Enzymol. 457, 349-372 (2009).</li></ol>

To successfully isolate mitochondria using this protocol it is essential to keep all solutions and tissue samples on ice to preserve mitochondrial viability. Even when maintained on ice, isolated mitochondria will exhibit a decrease in functional activity over time19. We recommend that all solutions and additions be pre-prepared. We pre-weigh and store Subtilisin A in 4 mg aliquots in 1.5 ml microfuge tubes and store them at -20 &#176;C. Similarly BSA is pre-weighed and stored in 20 mg aliquots in 1.5 ml micro...

A correction was made to: <a href="http://www.jove.com/video/51682">Rapid Isolation And Purification Of Mitochondria For Transplantation By Tissue Dissociation And Differential Filtration.</a> An optional step was added to step 7 of the &#39;Mitochondrial Isolation&#39; section of the protocol. The step is:
1. Optional in the case that the tissue is fibrous: Centrifuge the solution at 750 x g for 4 min.

A correction was made to: Rapid Isolation And Purification Of Mitochondria For Transplantation By Tissue Dissociation And Differential Filtration.

Erratum: Rapid Isolation And Purification Of Mitochondria For Transplantation By Tissue Dissociation And Differential Filtration

Mitochondria exist in every cell in the body except red blood cells and are involved in a large number of important cellular and metabolic processes1-4. Because of these many functions, mitochondrial damage can have detrimental effects3. In order to investigate mitochondrial function and dysfunction several mitochondrial isolation methods have been described. The earliest published accounts of mitochondrial isolation date to the 1940s5-8. The first documented attempt demonstrated mitochondrial isolation by grinding liver tissue in a mortar followed by centrifugation in a salt solution at low speed5,8. Later, other groups expanded upon the original procedure and demonstrated tissue fractionation based on differential centrifugation6-8. These early methods formed the basis of current techniques which often incorporate homogenization, and/or differential centrifugation9-15. The number of homogenization and centrifugation steps varies among protocols. These repetitive steps increase the time for mitochondrial isolation and ultimately reduce viability. In addition, manual homogenization can cause mitochondrial damage and inconsistent results if not properly controlled10,16.
Recently, we used homogenization and differential centrifugation to isolate mitochondria for transplantation into myocardial tissue17,18. This lengthy isolation procedure required approximately 90 min and the clinical applicability of this method was therefore limited. To allow for acute therapeutic use in clinical and surgical treatment we have developed a rapid mitochondrial isolation procedure that can be performed in less than 30 min.
The major benefits of this protocol are that standardized tissue dissociation allows for uniform and consistent homogenization of tissue that is not easily achieved with manual homogenization. In addition, the use of differential filtration in place of differential centrifugation eliminates time consuming and repetitive centrifugation steps allowing for more rapid isolation of highly purified, viable and respiration competent mitochondria.
The ability to isolate viable and respiration competent mitochondria in less than 30 min allows for clinical applicability. This isolation protocol has potential for use in coronary artery bypass grafting surgery (CABG) and other therapeutic procedures.

<table border="0" cellpadding="0" cellspacing="0" width="933">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:377px;">Sucrose</td>
			<td style="width:181px;">Sigma Aldrich</td>
			<td style="width:147px;">84100</td>
			<td style="width:229px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">HEPES</td>
			<td>Sigma Aldrich</td>
			<td>H4034</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">EGTA</td>
			<td>Sigma Aldrich</td>
			<td>E4378</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Substilsin A</td>
			<td>Sigma Aldrich</td>
			<td>P5380</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">BSA</td>
			<td>Sigma Aldrich</td>
			<td>A7906</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">KH2PO4</td>
			<td>Sigma Aldrich</td>
			<td>P5379</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">MgCl2</td>
			<td>Sigma Aldrich</td>
			<td>M8266</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">NaCl</td>
			<td>Sigma Aldrich</td>
			<td>S6191</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">KCl</td>
			<td>Fisher Scientific</td>
			<td>P2173</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Na2HPO4</td>
			<td>Fisher Scientific</td>
			<td>S374</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:377px;">ATPlite Luminescence Assay System, 
			1000 Assay Kit</td>
			<td>Perkin Elmer</td>
			<td>6016941</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Equipment</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">50 mL Conical Tubes</td>
			<td>BD</td>
			<td>352098</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">40 &#956;m Nylon Filters</td>
			<td>BD&#160;</td>
			<td>352340</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">GentleMACS C tube</td>
			<td>Miltenyl Biotech</td>
			<td>120-005-331</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1.5 mL Eppendorf tube</td>
			<td>Fisher Scientific</td>
			<td>05-408-129</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">6 mm biopsy punch</td>
			<td>Miltex</td>
			<td>33-36</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">10 &#956;m Pluristrainer</td>
			<td>Pluriselect</td>
			<td>43-500-10-03</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Eppendorf Centrifuge 5415C</td>
			<td>Marshall Scientific</td>
			<td>EP-5415C&#160;</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">GentleMACS Dissociator&#160;</td>
			<td>Miltenyl Biotech</td>
			<td>130-093-235</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">96-well plates, tissue culture treated</td>
			<td>VWR</td>
			<td>82050-732</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Rotomax 120 orbital shaker</td>
			<td>Heidolph</td>
			<td>544-41200-00</td>
			<td></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;">Synergy H4 Hybrid Multi-Mode 
			&#160;Microplate Reader</td>
			<td>BioTek</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Multisizer 4 Coulter Counter</td>
			<td>Beckman Coulter</td>
			<td>A63076</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Oxytherm System</td>
			<td>Hansatech Instruments</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hemacytometer</td>
			<td>Fisher Scientific</td>
			<td>267110</td>
			<td></td>
		</tr>
	</tbody>
</table>

rapid isolation and purification of mitochondria for transplantation by tissue dissociation and differential filtration

Previously described mitochondrial isolation methods using differential centrifugation and/or Ficoll gradient centrifugation require 60 to 100 min to complete. We describe a method for the rapid isolation of mitochondria from mammalian biopsies using a commercial tissue dissociator and differential filtration. In this protocol, manual homogenization is replaced with the tissue dissociator&#8217;s standardized homogenization cycle. This allows for uniform and consistent homogenization of tissue that is not easily achieved with manual homogenization. Following tissue dissociation, the homogenate is filtered through nylon mesh filters, which eliminate repetitive centrifugation steps. As a result, mitochondrial isolation can be performed in less than 30 min. This isolation protocol yields approximately 2 x 1010 viable and respiration competent mitochondria from 0.18 &#177; 0.04 g (wet weight) tissue sample.

A figure outlining the procedural steps in the isolation of mitochondria using tissue dissociation and differential filtration is shown in Figure 1. Total procedural time is less than 30 min.
Tissue samples were obtained using a 6 mm biopsy punch. Tissue weight was 0.18 &#177; 0.04 g (wet weight). The number of mitochondria isolated as determined by particle size counting was 2.4 x 1010 &#177; 0.1 x 1010 mitochondria for skeletal muscle and 2.75 x 10...

Watch this Scientific Journal Video about Rapid Isolation And Purification Of Mitochondria For Transplantation By Tissue Dissociation And Differential Filtration at JoVE.com

Rapid Isolation And Purification Of Mitochondria For Transplantation By Tissue Dissociation And Differential Filtration

A method for rapid isolation of mitochondria from mammalian tissue biopsies is described. Rat liver or skeletal muscle preparations were homogenized with a commercial tissue dissociator and mitochondria were isolated by differential filtration through nylon mesh filters. Mitochondrial isolation time is &#60;30 min compared to 60 - 100 min using alternative methods.

Previously described mitochondrial isolation methods using differential centrifugation and/or Ficoll gradient centrifugation require 60 to 100 min to ...

rapid-isolation-purification-mitochondria-for-transplantation-tissue

Research

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Biology

Isolation and Transplantation of Hematopoietic Stem Cells (HSCs)

Isolation and Transplantation of Hematopoietic Stem Cells HSCs

Staining of Proteins in Gels with Coomassie G-250 without Organic Solvent and Acetic Acid

In classical protein staining protocols using Coomassie Brilliant Blue (CBB), solutions with high contents of toxic and flammable organic solvents (Methanol, Ethanol or 2-Propanol) and acetic acid are used for fixation, staining and destaining of proteins in a gel after SDS-PAGE. To speed up the procedure, heating the staining solution in the microwave oven for a short time is frequently used. This usually results in evaporation of toxic or hazardous Methanol, Ethanol or 2-Propanol and a strong smell of acetic acid in the lab which should be avoided due to safety considerations. In a protocol originally published in two patent applications by E.M. Wondrak (US2001046709 (A1), US6319720 (B1)), an alternative composition of the staining solution is described in which no organic solvent or acid is used. The CBB is dissolved in bidistilled water (60-80mg of CBB G-250 per liter) and 35 mM HCl is added as the only other compound in the staining solution. The CBB staning of the gel is done after SDS-PAGE and thorough washing of the gel in bidistilled water. By heating the gel during the washing and staining steps, the process can be finished faster and no toxic or hazardous compunds are evaporating. The staining of proteins occurs already within 1 minute after heating the gel in staining solution and is fully developed after 15-30 min with a slightly blue background that is destained completely by prolonged washing of the stained gel in bidistilled water, without affecting the stained protein bands.

A short protocol for protein staining with Coomassie Brilliant Blue (CBB) G-250 in polyacrylamide gels is described without using organic solvents or acetic acid as in the classical staining procedures with CBB.

In classical protein staining protocols using Coomassie Brilliant Blue (CBB), solutions with high contents of toxic and flammable organic solvents ...

Purification of Mitochondria from Yeast Cells

Mitochondria are the main site of ATP production during aerobic metabolism in eukaryotic non-photosynthetic cells1. These complex organelles also play essential roles in apoptotic cell death2, cell survival3, mammalian development4, neuronal development and function4, intracellular signalling5, and longevity regulation6. Our understanding of these complex biological processes controlled by mitochondria relies on robust methods for assessing their morphology, their protein and lipid composition, the integrity of their DNA, and their numerous vital functions. The budding yeast Saccharomyces cerevisiae, a genetically and biochemically manipulable unicellular eukaryote with annotated genome and well-defined proteome, is a valuable model for studying the molecular and cellular mechanisms underlying essential biological functions of mitochondria. For these types of studies, it is crucial to have highly pure mitochondria. Here we present a detailed description of a rapid and effective method for purification of yeast mitochondria. This method enables the isolation of highly pure mitochondria that are essentially free of contamination by other organelles and retain their structural and functional integrity after their purification. Mitochondria purified by this method are suitable for cell-free reconstitution of essential mitochondrial processes and can be used for the analysis of mitochondrial structure and functions, mitochondrial proteome and lipidome, and mitochondrial DNA.

We describe a rapid and effective method for purification of mitochondria from the yeast Saccharomyces cerevisiae. This method enables the high-yield isolation of pure mitochondria that are essentially free of contamination by other organelles and retain their structural and functional integrity after their purification.

Mitochondria are the main site of ATP production during aerobic metabolism in eukaryotic non-photosynthetic cells1. These complex organelles also play ...

Isolation and Purification of Drosophila Peripheral Neurons by Magnetic Bead Sorting

The Drosophila peripheral nervous system (PNS) is a powerful model for investigating the complex processes of neuronal development and dendrite morphogenesis at the functional and molecular levels. To aid in these analyses, we have developed a strategy for the isolation of a subclass of PNS neurons called dendritic arborization (da) neurons that have been widely used for studying dendrite morphogenesis1,2. These neurons are very difficult to isolate as a pure population, due in part to their extremely low occurrence and their difficult-to-reach location below the tough chitinous larval cuticle. Our newly developed method overcomes these challenges, and is based on a fast and specific cell enrichment using antibody-coated magnetic beads. For our magnetic bead sorting studies, we have used age-matched third instar larvae expressing a mouse CD8 tagged GFP fusion protein (UAS-mCD8-GFP)3 under the control of either the class IV dendritic arborization (da) neuron-specific pickpocket (ppk)-GAL4 driver4 or the control of the pan-da neuron-specific GAL421-7 driver5. Although this protocol has been optimized for isolating PNS cells which are attached to the inner wall of the larval cuticle, by varying a few parameters, the same protocol could be used to isolate many different cell types attached to the cuticle at larval or pupal stages of development (e.g. epithelia, muscle, oenocytes etc.), or other cell types from larval organs depending upon the GAL4-specific driver expression pattern. The RNA isolated by this method is of high quality and can be readily used for downstream genomic analyses such as microarray gene expression profiling studies. This approach offers a powerful new tool to perform studies on isolated Drosophila dendritic arborization (da) neurons thereby providing novel insights into the molecular mechanisms underlying dendrite morphogenesis.

Isolation and Purification of Drosophila Peripheral Neurons by Magnetic Bead Sorting

In this video-article we present a method for the isolation and purification of Drosophila peripheral neurons using a fast magnetic bead assisted cell sorting strategy. RNA obtained from the isolated cells can be readily used for downstream applications including microarray analyses.

The Drosophila peripheral nervous system (PNS) is a powerful model for investigating the complex processes of neuronal development and dendrite ...

Chromatin Isolation by RNA Purification (ChIRP)

Long noncoding RNAs are key regulators of chromatin states for important biological processes such as dosage compensation, imprinting, and developmental gene expression 1,2,3,4,5,6,7. The recent discovery of thousands of lncRNAs in association with specific chromatin modification complexes, such as Polycomb Repressive Complex 2 (PRC2) that mediates histone H3 lysine 27 trimethylation (H3K27me3), suggests broad roles for numerous lncRNAs in managing chromatin states in a gene-specific fashion 8,9. While some lncRNAs are thought to work in cis on neighboring genes, other lncRNAs work in trans to regulate distantly located genes. For instance, Drosophila lncRNAs roX1 and roX2 bind numerous regions on the X chromosome of male cells, and are critical for dosage compensation 10,11. However, the exact locations of their binding sites are not known at high resolution. Similarly, human lncRNA HOTAIR can affect PRC2 occupancy on hundreds of genes genome-wide 3,12,13, but how specificity is achieved is unclear. LncRNAs can also serve as modular scaffolds to recruit the assembly of multiple protein complexes. The classic trans-acting RNA scaffold is the TERC RNA that serves as the template and scaffold for the telomerase complex 14; HOTAIR can also serve as a scaffold for PRC2 and a H3K4 demethylase complex 13.
Prior studies mapping RNA occupancy at chromatin have revealed substantial insights 15,16, but only at a single gene locus at a time. The occupancy sites of most lncRNAs are not known, and the roles of lncRNAs in chromatin regulation have been mostly inferred from the indirect effects of lncRNA perturbation. Just as chromatin immunoprecipitation followed by microarray or deep sequencing (ChIP-chip or ChIP-seq, respectively) has greatly improved our understanding of protein-DNA interactions on a genomic scale, here we illustrate a recently published strategy to map long RNA occupancy genome-wide at high resolution 17. This method, Chromatin Isolation by RNA Purification (ChIRP) (Figure 1), is based on affinity capture of target lncRNA:chromatin complex by tiling antisense-oligos, which then generates a map of genomic binding sites at a resolution of several hundred bases with high sensitivity and low background. ChIRP is applicable to many lncRNAs because the design of affinity-probes is straightforward given the RNA sequence and requires no knowledge of the RNA's structure or functional domains.

Chromatin Isolation by RNA Purification ChIRP

ChIRP is a novel and rapid technique to map genomic binding sites of long noncoding RNAs (lncRNAs). The method takes advantage of the specificity of anti-sense tiling oligonucleotides to allow the enumeration of lncRNA-bound genomic sites.

Long noncoding RNAs are key regulators of chromatin states for important biological processes such as dosage compensation, imprinting, and developmental ...

Planarian Immobilization, Partial Irradiation, and Tissue Transplantation

The planarian, a freshwater flatworm, has proven to be a powerful system for dissecting metazoan regeneration and stem cell biology1,2. Planarian regeneration of any missing or damaged tissues is made possible by adult stem cells termed neoblasts3. Although these stem cells have been definitively shown to be pluripotent and singularly capable of reconstituting an entire animal4, the heterogeneity within the stem cell population and the dynamics of their cellular behaviors remain largely unresolved. Due to the large number and wide distribution of stem cells throughout the planarian body plan, advanced methods for manipulating subpopulations of stem cells for molecular and functional study in vivo are needed.
Tissue transplantation and partial irradiation are two methods by which a subpopulation of planarian stem cells can be isolated for further study. Each technique has distinct advantages. Tissue transplantation allows for the introduction of stem cells, into a na&iuml;ve host, that are either inherently genetically distinct or have been previously treated pharmacologically. Alternatively, partial irradiation allows for the isolation of stem cells within a host, juxtaposed to tissue devoid of stem cells, without the introduction of a wound or any breech in tissue integrity. Using these two methods, one can investigate the cell autonomous and non-autonomous factors that control stem cell functions, such as proliferation, differentiation, and migration.
Both tissue transplantation5,6 and partial irradiation7 have been used historically in defining many of the questions about planarian regeneration that remain under study today. However, these techniques have remained underused due to the laborious and inconsistent nature of previous methods. The protocols presented here represent a large step forward in decreasing the time and effort necessary to reproducibly generate large numbers of grafted or partially irradiated animals with efficacies approaching 100 percent. We cover the culture of large animals, immobilization, preparation for partial irradiation, tissue transplantation, and the optimization of animal recovery. Furthermore, the work described here demonstrates the first application of the partial irradiation method for use with the most widely studied planarian, Schmidtea mediterranea. Additionally, efficient tissue grafting in planaria opens the door for the functional testing of subpopulations of na&iuml;ve or treated stem cells in repopulation assays, which has long been the gold-standard method of assaying adult stem cell potential in mammals8. Broad adoption of these techniques will no doubt lead to a better understanding of the cellular behaviors of adult stem cells during tissue homeostasis and regeneration.

An effective method for grafting tissue of defined and consistent size between planaria is described. Also included is a description of how the immobilization technique used for transplantation can be adapted, in conjunction with lead shields, for the partial irradiation of live animals.

The planarian, a freshwater flatworm, has proven to be a powerful system for dissecting metazoan regeneration and stem cell biology1,2. Planarian ...

Isolation, Culture, and Transplantation of Muscle Satellite Cells

Muscle satellite cells are a stem cell population required for postnatal skeletal muscle development and regeneration, accounting for 2-5% of sublaminal nuclei in muscle fibers. In adult muscle, satellite cells are normally mitotically quiescent. Following injury, however, satellite cells initiate cellular proliferation to produce myoblasts, their progenies, to mediate the regeneration of muscle. Transplantation of satellite cell-derived myoblasts has been widely studied as a possible therapy for several regenerative diseases including muscular dystrophy, heart failure, and urological dysfunction. Myoblast transplantation into dystrophic skeletal muscle, infarcted heart, and dysfunctioning urinary ducts has shown that engrafted myoblasts can differentiate into muscle fibers in the host tissues and display partial functional improvement in these diseases. Therefore, the development of efficient purification methods of quiescent satellite cells from skeletal muscle, as well as the establishment of satellite cell-derived myoblast cultures and transplantation methods for myoblasts, are essential for understanding the molecular mechanisms behind satellite cell self-renewal, activation, and differentiation. Additionally, the development of cell-based therapies for muscular dystrophy and other regenerative diseases are also dependent upon these factors.

However, current prospective purification methods of quiescent satellite cells require the use of expensive fluorescence-activated cell sorting (FACS) machines. Here, we present a new method for the rapid, economical, and reliable purification of quiescent satellite cells from adult mouse skeletal muscle by enzymatic dissociation followed by magnetic-activated cell sorting (MACS). Following isolation of pure quiescent satellite cells, these cells can be cultured to obtain large numbers of myoblasts after several passages. These freshly isolated quiescent satellite cells or ex vivo expanded myoblasts can be transplanted into cardiotoxin (CTX)-induced regenerating mouse skeletal muscle to examine the contribution of donor-derived cells to regenerating muscle fibers, as well as to satellite cell compartments for the examination of self-renewal activities.

The isolation and culture of a pure population of quiescent satellite cells, a muscle stem cell population, is essential to the understanding of muscle stem cell biology and regeneration, as well as stem cell transplantation for therapies in muscular dystrophy and other degenerative diseases.&#160;

Muscle satellite cells are a stem cell population required for postnatal skeletal muscle development and regeneration, accounting for 2-5% of sublaminal ...

Isolation and Functional Analysis of Mitochondria from Cultured Cells and Mouse Tissue

Comparison between two or more distinct groups, such as healthy vs. disease, is necessary to determine cellular status. Mitochondria are at the nexus of cell heath due to their role in both cell metabolism and energy production as well as control of apoptosis. Therefore, direct evaluation of isolated mitochondria and mitochondrial perturbation offers the ability to determine if organelle-specific (dys)function is occurring. The methods described in this protocol include isolation of intact, functional mitochondria from HEK cultured cells and mouse liver and spinal cord, but can be easily adapted for use with other cultured cells or animal tissues. Mitochondrial function assessed by TMRE and the use of common mitochondrial uncouplers and inhibitors in conjunction with a fluorescent plate reader allow this protocol not only to be versatile and accessible to most research laboratories, but also offers high throughput.

Comparison of mitochondrial membrane potential between samples yields valuable information about cellular status. Detailed steps for isolating mitochondria and assessing response to inhibitors and uncouplers using fluorescence are described. The method and utility of this protocol are illustrated by use of a cell culture and animal model of cellular stress.

Comparison between two or more distinct groups, such as healthy vs. disease, is necessary to determine cellular status. Mitochondria are at the nexus of ...

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.

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

Isolation of Intact Mitochondria from Skeletal Muscle by Differential Centrifugation for High-resolution Respirometry Measurements

Mitochondria are involved in cellular energy metabolism and use oxygen to produce energy in the form of adenosine triphosphate (ATP). Differential centrifugation at low- and high-speed is commonly used to isolate mitochondria from tissues and cultured cells. Crude mitochondrial fractions obtained by differential centrifugation are used for respirometry measurements. The differential centrifugation technique is based on the separation of organelles according to their size and sedimentation velocity. The isolation of mitochondria is performed immediately after tissue harvesting. The tissue is immersed in an ice-cold homogenization medium, minced using scissors and homogenized in a glass homogenizer with a loose-fitting pestle. The differential centrifugation technique is efficient, fast and inexpensive and the mitochondria obtained by differential centrifugation are pure enough for respirometry assays. Some of the limitations and disadvantages of isolated mitochondria, based on differential centrifugation, are that the mitochondria can be damaged during the homogenization and isolation procedure and that large amounts of the tissue biopsy or cultured cells are required for the mitochondrial isolation.

Here, a quadriceps muscle specimen is taken from an anaesthetized pig and mitochondria are isolated by differential centrifugation. Then, the respiratory rates of mitochondrial respiratory chain complexes I, II and IV are determined using high-resolution respirometry.