Este trabajo fue apoyado por fondos de la DZNE y una beca de reinserción Marie Curie Internacional (322120 a D.C.D.)

<ol>
	<li>Balch, W. E., Morimoto, R. I., Dillin, A., Kelly, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adapting+proteostasis+for+disease+intervention.">Adapting proteostasis for disease intervention.</a> Science. 319, 916-919 (2008).</li><li>David, 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=Aging+and+the+aggregating+proteome.">Aging and the aggregating proteome.</a> Frontiers in genetics. 3, 247 (2012).</li><li>Hartl, F. U., Bracher, A., Hayer-Hartl, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+chaperones+in+protein+folding+and+proteostasis.">Molecular chaperones in protein folding and proteostasis.</a> Nature. 475, 324-332 (2011).</li><li>Ayyadevara, 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=Age-+and+Hypertension-Associated+Protein+Aggregates+in+Mouse+Heart+Have+Similar+Proteomic+Profiles.">Age- and Hypertension-Associated Protein Aggregates in Mouse Heart Have Similar Proteomic Profiles.</a> Hypertension. 67, 1006-1013 (2016).</li><li>David, D. 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=Widespread+protein+aggregation+as+an+inherent+part+of+aging+in+C.+elegans.">Widespread protein aggregation as an inherent part of aging in C. elegans.</a> PLoS biology. 8, 1000450 (2010).</li><li>Demontis, F., Perrimon, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=FOXO/4E-BP+signaling+in+Drosophila+muscles+regulates+organism-wide+proteostasis+during+aging.">FOXO/4E-BP signaling in Drosophila muscles regulates organism-wide proteostasis during aging.</a> Cell. 143, 813-825 (2010).</li><li>Lechler, M. 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=Reduced+Insulin/IGF-1+Signaling+Restores+the+Dynamic+Properties+of+Key+Stress+Granule+Proteins+during+Aging.">Reduced Insulin/IGF-1 Signaling Restores the Dynamic Properties of Key Stress Granule Proteins during Aging.</a> Cell reports. 18, 454-467 (2017).</li><li>Reis-Rodrigues, P., 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=Proteomic+analysis+of+age-dependent+changes+in+protein+solubility+identifies+genes+that+modulate+lifespan.">Proteomic analysis of age-dependent changes in protein solubility identifies genes that modulate lifespan.</a> Aging cell. 11, 120-127 (2012).</li><li>Tanase, 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=Role+of+Carbonyl+Modifications+on+Aging-Associated+Protein+Aggregation.">Role of Carbonyl Modifications on Aging-Associated Protein Aggregation.</a> Scientific reports. 6, 19311 (2016).</li><li>Walther, D. 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=Widespread+Proteome+Remodeling+and+Aggregation+in+Aging+C.+elegans.">Widespread Proteome Remodeling and Aggregation in Aging C. elegans.</a> Cell. 161, 919-932 (2015).</li><li>Lee, V. M., Wang, J., Trojanowski, J. Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Purification+of+paired+helical+filament+tau+and+normal+tau+from+human+brain+tissue.">Purification of paired helical filament tau and normal tau from human brain tissue.</a> Methods in enzymology. 309, 81-89 (1999).</li><li>Goudeau, J., Aguilaniu, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Carbonylated+proteins+are+eliminated+during+reproduction+in+C.+elegans.">Carbonylated proteins are eliminated during reproduction in C. elegans.</a> Aging cell. 9, 991-1003 (2010).</li><li>Zimmerman, S. M., Hinkson, I. V., Elias, J. E., Kim, S. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reproductive+Aging+Drives+Protein+Accumulation+in+the+Uterus+and+Limits+Lifespan+in+C.+elegans.">Reproductive Aging Drives Protein Accumulation in the Uterus and Limits Lifespan in C. elegans.</a> PLoS genetics. 11, 1005725 (2015).</li><li>Uno, M., Nishida, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lifespan-regulating+genes+in+C.+elegans.">Lifespan-regulating genes in C. elegans.</a> Npj Aging And Mechanisms Of Disease. 2, 16010 (2016).</li><li>Sulston, J. H. <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 Nematode Caenorhabditis elegans. , 587-606 (1988).</li><li>Maine, E. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=RNAi+As+a+tool+for+understanding+germline+development+in+Caenorhabditis+elegans:+uses+and+cautions.">RNAi As a tool for understanding germline development in Caenorhabditis elegans: uses and cautions.</a> Developmental biology. 239, 177-189 (2001).</li><li>Rauniyar, N., Yates, 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=Isobaric+labeling-based+relative+quantification+in+shotgun+proteomics.">Isobaric labeling-based relative quantification in shotgun proteomics.</a> Journal of proteome research. 13, 5293-5309 (2014).</li><li>Brignull, H. R., Morley, J. F., Garcia, S. M., Morimoto, R. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modeling+polyglutamine+pathogenesis+in+C.+elegans.">Modeling polyglutamine pathogenesis in C. elegans.</a> Methods in enzymology. 412, 256-282 (2006).</li><li>Fay, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Classical+genetic+methods.">Classical genetic methods.</a> WormBook. , 1-58 (2013).</li><li>Brunquell, J., Bowers, P., Westerheide, S. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fluorodeoxyuridine+enhances+the+heat+shock+response+and+decreases+polyglutamine+aggregation+in+an+HSF-1-dependent+manner+in+Caenorhabditis+elegans.">Fluorodeoxyuridine enhances the heat shock response and decreases polyglutamine aggregation in an HSF-1-dependent manner in Caenorhabditis elegans.</a> Mech Ageing Dev. 141, 1-4 (2014).</li><li>Angeli, 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+DNA+synthesis+inhibitor+is+protective+against+proteotoxic+stressors+via+modulation+of+fertility+pathways+in+Caenorhabditis+elegans.">A DNA synthesis inhibitor is protective against proteotoxic stressors via modulation of fertility pathways in Caenorhabditis elegans.</a> Aging (Albany NY). 5, 759-769 (2013).</li><li>Feldman, N., Kosolapov, L., Ben-Zvi, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fluorodeoxyuridine+improves+Caenorhabditis+elegans+proteostasis+independent+of+reproduction+onset.">Fluorodeoxyuridine improves Caenorhabditis elegans proteostasis independent of reproduction onset.</a> PLoS One. 9, 85964 (2014).</li><li>Davies, S. K., Leroi, A. M., Bundy, J. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fluorodeoxyuridine+affects+the+identification+of+metabolic+responses+to+daf-2+status+in+Caenorhabditis+elegans.">Fluorodeoxyuridine affects the identification of metabolic responses to daf-2 status in Caenorhabditis elegans.</a> Mech Ageing Dev. 133, 46-49 (2012).</li><li>Luo, S., Kleemann, G. A., Ashraf, J. M., Shaw, W. M., Murphy, C. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=TGF-beta+and+insulin+signaling+regulate+reproductive+aging+via+oocyte+and+germline+quality+maintenance.">TGF-beta and insulin signaling regulate reproductive aging via oocyte and germline quality maintenance.</a> Cell. 143, 299-312 (2010).</li><li>Andux, S., Ellis, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Apoptosis+maintains+oocyte+quality+in+aging+Caenorhabditis+elegans+females.">Apoptosis maintains oocyte quality in aging Caenorhabditis elegans females.</a> PLoS genetics. 4, 1000295 (2008).</li><li>Vilchez, 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=RPN-6+determines+C.+elegans+longevity+under+proteotoxic+stress+conditions.">RPN-6 determines C. elegans longevity under proteotoxic stress conditions.</a> Nature. 489, 263-268 (2012).</li><li>Ghazi, A., Henis-Korenblit, S., Kenyon, 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+transcription+elongation+factor+that+links+signals+from+the+reproductive+system+to+lifespan+extension+in+Caenorhabditis+elegans.">A transcription elongation factor that links signals from the reproductive system to lifespan extension in Caenorhabditis elegans.</a> PLoS genetics. 5, 1000639 (2009).</li><li>Shemesh, N., Shai, N., Meshnik, L., Katalan, R., Ben-Zvi, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Uncoupling+the+Trade-Off+between+Somatic+Proteostasis+and+Reproduction+in+Caenorhabditis+elegans+Models+of+Polyglutamine+Diseases.">Uncoupling the Trade-Off between Somatic Proteostasis and Reproduction in Caenorhabditis elegans Models of Polyglutamine Diseases.</a> Front Mol Neurosci. 10, 101 (2017).</li><li>Kaletsky, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+C.+elegans+adult+neuronal+IIS/FOXO+transcriptome+reveals+adult+phenotype+regulators.">The C. elegans adult neuronal IIS/FOXO transcriptome reveals adult phenotype regulators.</a> Nature. 529, 92-96 (2016).</li><li>Kawarabayashi, T., 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=Age-dependent+changes+in+brain,+CSF,+and+plasma+amyloid+(beta)+protein+in+the+Tg2576+transgenic+mouse+model+of+Alzheimer's+disease.">Age-dependent changes in brain, CSF, and plasma amyloid (beta) protein in the Tg2576 transgenic mouse model of Alzheimer's disease.</a> The Journal of neuroscience : the official journal of the Society for Neuroscience. 21, 372-381 (2001).</li><li>Kraemer, B. 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=Neurodegeneration+and+defective+neurotransmission+in+a+Caenorhabditis+elegans+model+of+tauopathy.">Neurodegeneration and defective neurotransmission in a Caenorhabditis elegans model of tauopathy.</a> Proceedings of the National Academy of Sciences of the United States of America. 100, 9980-9985 (2003).</li></ol>

Los autores no tienen nada que revelar.

Aquí se presenta una metodología para aislar a agregados de proteína altamente insoluble de envejecimiento C. elegans sometidos a ARNi para análisis por espectrometría de masas y Western blotting. Mostramos que mejorar proteostasis reduciendo grandemente IIS previene la agregación de proteínas dependientes de la edad. Por selección de proteínas específicas propensas a la agregación que sobreexpresan en C. elegans, es posible disecar más los mecanismos de modulación de agregación de la prot...

Agregación y mal plegamiento de proteínas son reconocidas como una seña de identidad de varias enfermedades neurodegenerativas tales como AD, enfermedad de Parkinson, esclerosis lateral amiotrófica (ELA), la demencia frontotemporal (FTD) y muchos otros. Por ejemplo, asambleas de α-sinucleína en fibrillas amiloides que se acumulan como los cuerpos de Lewy particularmente en el nigra del substantia de los pacientes con EP, mientras que en misfold de TDP-43 o FUS de pacientes ALS para formar agregados citoplasmáticos en degeneración de las neuronas motoras. En cada uno de estos trastornos neurodegenerativos, mecanismos de mantenimiento de la homeostasis de proteínas o proteostasis no evitar la acumulación de proteínas mal plegadas, por lo tanto conduce a la enfermedad.
Proteostasis es crucial para las funciones celulares y bajo condiciones normales estos mecanismos controlan firmemente la tasa de síntesis de proteínas, plegamiento y degradación. Varios estudios demuestran que con el envejecimiento, la capacidad de muchas células y órganos para mantener la homeostasis de proteínas poco a poco se ve comprometida y el deterioro fisiológico de las redes proteostasis con la edad es un factor agravante importante para enfermedades neurodegenerativas (revisadas en las referencias1,2,3). El hecho de que el control de calidad de la proteína y la respuesta celular al estrés proteínas desplegadas se comprometen con la edad sugiere que el mal plegamiento de proteínas y agregación podrían ser una general consecuencia del envejecimiento. De hecho, nosotros y otros hemos demostrado que la agregación de la proteína no se limita a la enfermedad y en cambio parte del proteoma se convierte en altamente insoluble en detergente en animales envejecidos4,5,6,7 ,8,9,10. Análisis computacional e in vivo revelaron que estos agregados relacionados con la edad fisiológicos se asemejan a agregados de la enfermedad en varios aspectos5. El descubrimiento de la agregación de proteína endógena, dependiente de la edad nos da la oportunidad de diseccionar los mecanismos moleculares y celulares que regulan la agregación de proteínas, sin utilizar ectopically expresadas proteínas humanas asociadas a la enfermedad. En la actualidad, solamente poca información existe sobre la regulación de la insolubilidad de la proteína generalizada y sobre los efectos de esta disregulación en la salud del organismo.
El nematodo C. elegans es uno de los organismos modelo más extensamente estudiados en la investigación del envejecimiento ya que estos animales tienen una vida útil relativamente corta y muestran muchas características de envejecimiento característico observados en organismos superiores. Los efectos del envejecimiento en la insolubilidad de la proteína han sido estudiados en C. elegans por fraccionamiento bioquímico secuencial basado en la solubilidad diferencial, que es ampliamente utilizado para extraer áridos de la enfermedad en el campo de la investigación neurodegeneración11 . Por espectrometría de masa cuantitativa, varias cientos proteínas fueron demostradas para ser agregación-propensa en C. elegans en la ausencia de enfermedad5. Aquí describimos en detalle el protocolo para cultivar grandes cantidades de gusanos en cultivo líquido y la extracción secuencial para aislar proteínas agregadas para la cuantificación por espectrometría de masas y el análisis por Western blot. Porque las proteínas mal plegadas y propensas a la agregación se acumulan en mayores cambios de gónadas y máscaras de C. elegans en otros tejidos somáticos5,12,13, utilizamos un mutante de la gónada menos centrarse el análisis de proteínas insolubilidad en los tejidos no reproductivos. El método permite el análisis de los agregados altamente insoluble, grandes que son insolubles en 0,5% SDS y sedimentados por la relativamente baja velocidad centrífuga. Por otra parte, un protocolo de extracción menos riguroso para recoger también agregados más pequeños y más solubles ha sido publicado en otra parte10. Además, se describe el método utilizado para evaluar la agregación en vivo en C. elegans.
En general, estos métodos en combinación con el ARN de interferencia (ARNi) pueden evaluar la función de un gen de interés en la modulación de agregación de la proteína depende de la edad. Para ello se describe el análisis de extractos de gusanos jóvenes y mayores con y sin precipitación de una proteína específica de interés utilizando RNAi. Estos métodos deben ser una herramienta poderosa para determinar que los componentes de la red proteostasis regulan insolubilidad de la proteína. Varias intervenciones tales como reducción la insulina/insulina-like growth factor (IGF) 1 señalización (IIS) se ha demostrado que retrasar dramáticamente C. elegans envejecimiento14. Vías de longevidad a menudo inducen mecanismos de control de calidad de la proteína y así estas vías podrían ser activamente influir en la tasa de agregación de la proteína. Por ejemplo, nos demuestran agregación reducida proteína inherente en animales de larga vida sobre la inhibición de la vía IIS7.

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		<col style="width:92pt" width="122" />
		<col style="width:258pt" width="344" />
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	</colgroup>
	<tbody>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="width:161pt;height:30.0pt" width="215">Fernbach culture flask&#160;</td>
			<td class="xl18" style="width:92pt" width="122">Corning</td>
			<td class="xl19" style="width:258pt" width="344">4425-2XL</td>
			<td class="xl18" style="width:125pt" width="166">Pyrex, Capacity 2,800 ml, with 3 baffle indents</td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl18" height="40" style="width:161pt;height:30.0pt" width="215">Membrane Screw Cap&#160;</td>
			<td class="xl18" style="width:92pt" width="122">Schott</td>
			<td class="xl19">1088655</td>
			<td class="xl17">GL45</td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">Nutating Mixer</td>
			<td class="xl18" style="width:92pt" width="122">VWR</td>
			<td class="xl19">444-0148</td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">Separatory funnel</td>
			<td class="xl18" style="width:92pt" width="122">Nalgene</td>
			<td class="xl19">4300-1000</td>
			<td class="xl17">Capacity 1,000 ml</td>
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		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">1 ml syringe&#160;</td>
			<td class="xl18" style="width:92pt" width="122">BD Plastipak</td>
			<td class="xl19">300013</td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl18" height="40" style="width:161pt;height:30.0pt" width="215">Gray needle, 27 G x &#189; &#34;, 0.4 mm x 13 mm</td>
			<td class="xl18" style="width:92pt" width="122">BD Microlance 3</td>
			<td class="xl19">300635</td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">Membrane filters 0.025 &#181;M</td>
			<td class="xl18" style="width:92pt" width="122">Millipore</td>
			<td class="xl19">VSWP04700</td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">pH strip</td>
			<td class="xl18" style="width:92pt" width="122">Machery-Nagel</td>
			<td class="xl19">92110</td>
			<td class="xl17">pH-Fix 0-14</td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl18" height="40" style="width:161pt;height:30.0pt" width="215">Protease Inhibitor Cocktail</td>
			<td class="xl18" style="width:92pt" width="122">Roche</td>
			<td class="xl19">4693132001</td>
			<td class="xl16" style="width:125pt" width="166">Complete Mini EDTA-free tablets&#160;</td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">Octoxynol-9&#160;</td>
			<td class="xl18" style="width:92pt" width="122">Applichem</td>
			<td class="xl19">A1388</td>
			<td class="xl18" style="width:125pt" width="166">Triton X-100</td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl18" height="40" style="width:161pt;height:30.0pt" width="215">4-Morpholineethanesulfonic acid (MES)</td>
			<td class="xl18" style="width:92pt" width="122">Sigma-Aldrich</td>
			<td class="xl19">M1317</td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">Nonylphenylpolyethylenglycol</td>
			<td class="xl18" style="width:92pt" width="122">Applichem</td>
			<td class="xl19">A1694</td>
			<td class="xl18" style="width:125pt" width="166">Nonidet P40 (NP40)</td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">DNaseI</td>
			<td class="xl18" style="width:92pt" width="122">Roche</td>
			<td class="xl19">04716728001</td>
			<td class="xl18" style="width:125pt" width="166">recombinant, RNase free</td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">RNaseA</td>
			<td class="xl18" style="width:92pt" width="122">Promega</td>
			<td class="xl19">A7973</td>
			<td class="xl18" style="width:125pt" width="166">solution</td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl18" height="40" style="width:161pt;height:30.0pt" width="215">Total protein blot staining</td>
			<td class="xl18" style="width:92pt" width="122">Thermofisher</td>
			<td class="xl19">S11791</td>
			<td class="xl18" style="width:125pt" width="166">Sypro Ruby protein blot stain</td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl18" height="40" style="width:161pt;height:30.0pt" width="215">Total protein gel staining</td>
			<td class="xl18" style="width:92pt" width="122">Thermofisher</td>
			<td class="xl19">S12001</td>
			<td class="xl18" style="width:125pt" width="166">Sypro Ruby protein gel stain</td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl18" height="40" style="width:161pt;height:30.0pt" width="215">TCEP (tris (2-carboxyethyl) phosphine hydrochloride)</td>
			<td class="xl18" style="width:92pt" width="122">Serva</td>
			<td class="xl19">36970</td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl18" height="40" style="width:161pt;height:30.0pt" width="215">Iodoacetamide</td>
			<td class="xl18" style="width:92pt" width="122">Serva</td>
			<td class="xl19">26710</td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl18" height="40" style="width:161pt;height:30.0pt" width="215">Ammoniumbicarbonate</td>
			<td class="xl18" style="width:92pt" width="122">Sigma-Aldrich</td>
			<td class="xl19">09830</td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl18" height="40" style="width:161pt;height:30.0pt" width="215">Sequencing Grade Modified Trypsin</td>
			<td class="xl18" style="width:92pt" width="122">Promega</td>
			<td class="xl25" style="width:258pt" width="344">V5111</td>
			<td class="xl18" style="width:125pt" width="166"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl18" height="40" style="width:161pt;height:30.0pt" width="215">Isobaric tags for relative and absolute quantitation</td>
			<td class="xl18" style="width:92pt" width="122">Sciex</td>
			<td class="xl19">4352135</td>
			<td class="xl18" style="width:125pt" width="166">iTRAQ Reagents Multiplex Kit</td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">Centrifuge Avanti J-26XP</td>
			<td class="xl18" style="width:92pt" width="122">Beckmann Coulter</td>
			<td class="xl19">393126</td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">Ultracentrifuge Optima Max-XP</td>
			<td class="xl18" style="width:92pt" width="122">Beckmann Coulter</td>
			<td class="xl19">393315</td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">Centrifuge 5424R</td>
			<td class="xl18" style="width:92pt" width="122">Eppendorf</td>
			<td class="xl19">5404000413</td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">Centrifuge 5702</td>
			<td class="xl18" style="width:92pt" width="122">Eppendorf</td>
			<td class="xl19">5702000329</td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">Centrifuge Megafuge 40R</td>
			<td class="xl18" style="width:92pt" width="122">Thermo Scientific</td>
			<td class="xl19">75004518</td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">Concentrator Plus</td>
			<td class="xl18" style="width:92pt" width="122">Eppendorf</td>
			<td class="xl19">5305000304</td>
			<td class="xl17">Centrifugal evaporator</td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl18" height="40" style="width:161pt;height:30.0pt" width="215">Fluorescent stereo-microscope M165 FC&#160;</td>
			<td class="xl18" style="width:92pt" width="122">Leica</td>
			<td class="xl19"></td>
			<td class="xl18" style="width:125pt" width="166">With Planapo 2.0x objective</td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">Dissection microscope</td>
			<td class="xl18" style="width:92pt" width="122">Leica&#160;</td>
			<td class="xl19"></td>
			<td class="xl17">Leica S6E</td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl18" height="80" rowspan="2" style="width:161pt;height:60.0pt" width="215">High magnification microscope Zeiss Axio Observer Z1</td>
			<td class="xl18" height="80" rowspan="2" style="width:92pt;height:60.0pt" width="122">Zeiss</td>
			<td class="xl19" height="80" rowspan="2" style="width:258pt;height:60.0pt" width="344"></td>
			<td class="xl16" height="80" rowspan="2" style="width:125pt;height:60.0pt" width="166">With PlanAPOCHROMAT 20x objective and Zeiss Axio Cam MRm</td>
		</tr>
		<tr height="40" style="height:30.0pt">
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl32" height="40" style="height:30.0pt">Software</td>
			<td class="xl33" style="width:92pt" width="122"></td>
			<td class="xl32"></td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">Image analysis software</td>
			<td class="xl18" style="width:92pt" width="122">ImageJ</td>
			<td class="xl19"></td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl18" height="40" style="width:161pt;height:30.0pt" width="215">Analysis of mass spectrometry data</td>
			<td class="xl18" style="width:92pt" width="122">Protein Prospector</td>
			<td class="xl136" style="width:258pt" width="344"></td>
			<td class="xl137">http://prospector.ucsf.edu/prospector/mshome.htm</td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl32" height="40" style="height:30.0pt">E.coli strain</td>
			<td class="xl33" style="width:92pt" width="122"></td>
			<td class="xl19"></td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">OP50</td>
			<td class="xl18" style="width:92pt" width="122">CGC</td>
			<td class="xl19"></td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl32" height="40" style="height:30.0pt">RNAi bacteria</td>
			<td class="xl33" style="width:92pt" width="122"></td>
			<td class="xl19"></td>
			<td class="xl17"></td>
		</tr>
		<tr height="40" style="height:30.0pt">
			<td class="xl17" height="40" style="height:30.0pt">L4440</td>
			<td class="xl18" style="width:92pt" width="122">Julie Ahringer RNAi library</td>
			<td class="xl19"></td>
			<td class="xl17"></td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl32" height="42" rowspan="2" style="width:161pt;height:31.5pt" width="215">C. elegans mutants</td>
			<td class="xl33" height="42" rowspan="2" style="width:92pt;height:31.5pt" width="122"></td>
			<td class="xl32" height="42" rowspan="2" style="width:258pt;height:31.5pt" width="344"></td>
			<td class="xl19" height="42" rowspan="2" style="width:125pt;height:31.5pt" width="166"></td>
		</tr>
		<tr height="21" style="height:15.75pt">
		</tr>
		<tr height="42" style="height:31.5pt">
			<td class="xl17" height="42" style="height:31.5pt">CF2253</td>
			<td class="xl18" style="width:92pt" width="122">CGC, strain name: EJ1158&#160;</td>
			<td class="xl40" style="width:258pt" width="344"></td>
			<td class="xl17">Genotype: gon-2(q388)</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl33" height="42" rowspan="2" style="width:161pt;height:31.5pt" width="215">C. elegans transgenics</td>
			<td class="xl33" height="42" rowspan="2" style="width:92pt;height:31.5pt" width="122"></td>
			<td class="xl32" height="42" rowspan="2" style="width:258pt;height:31.5pt" width="344"></td>
			<td class="xl19" height="42" rowspan="2" style="width:125pt;height:31.5pt" width="166"></td>
		</tr>
		<tr height="21" style="height:15.75pt">
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl18" height="42" rowspan="2" style="width:161pt;height:31.5pt" width="215">DCD214</td>
			<td class="xl25" height="42" rowspan="2" style="width:92pt;height:31.5pt" width="122">Della David&#39;s lab at DZNE T&#252;bingen</td>
			<td class="xl40" height="42" rowspan="2" style="width:258pt;height:31.5pt" width="344"></td>
			<td class="xl68" height="42" rowspan="2" style="width:125pt;height:31.5pt" width="166">Genotype: N2; uqIs24[Pmyo-2::tagrfp::pab-1]</td>
		</tr>
		<tr height="21" style="height:15.75pt">
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl17" height="42" rowspan="2" style="width:161pt;height:31.5pt" width="215">DCD215</td>
			<td class="xl87" height="42" rowspan="2" style="width:92pt;height:31.5pt" width="122">Della David&#39;s lab at DZNE T&#252;bingen</td>
			<td class="xl40" height="42" rowspan="2" style="width:258pt;height:31.5pt" width="344"></td>
			<td class="xl68" height="42" rowspan="2" style="width:125pt;height:31.5pt" width="166">Genotype: daf-2(e1370) III; uqIs24[Pmyo-2::tagrfp::pab-1]</td>
		</tr>
		<tr height="21" style="height:15.75pt">
		</tr>
	</tbody>
</table>

methods to study changes in inherent protein aggregation with age in caenorhabditis elegans

En las últimas décadas, la prevalencia de trastornos neurodegenerativos, como la enfermedad de Alzheimer (EA) y enfermedad de Parkinson (EP), ha crecido. Estos trastornos asociados con la edad se caracterizan por la aparición de agregados de proteínas de estructura fibrilar en los cerebros de estos pacientes. Exactamente por qué proteínas solubles normalmente se someten a un proceso de agregación sigue siendo mal entendido. El descubrimiento que la agregación de la proteína no se limita a procesos de la enfermedad y en su lugar parte del proceso normal de envejecimiento permite el estudio de los mecanismos moleculares y celulares que regulan la agregación de proteínas, sin utilizar ectopically expresado humana proteínas asociadas a la enfermedad. Aquí se describen metodologías para examinar la agregación de proteínas inherentes en elegans de Caenorhabditis a través de enfoques complementarios. En primer lugar, examinamos cómo cultivar grandes cantidades de edad-que sincronizados C. elegans para la obtención de animales y presentamos los procedimientos bioquímicos para aislar altamente insoluble en grandes agregados. En combinación con una caída genética dirigida, es posible diseccionar el papel de un gen de interés en la promoción o prevención de la agregación de proteínas dependientes de la edad usando ya sea un análisis exhaustivo con espectrometría de masas cuantitativo o una Análisis basado en el candidato con los anticuerpos. Estos resultados son luego confirmados por análisis en vivo con animales transgénicos expresando con etiquetas fluorescentes propensas a la agregación de proteínas. Estos métodos deberían ayudar a aclarar por qué ciertas proteínas son propensos a agregado con la edad y, en definitiva, cómo mantener estas proteínas completamente funcional.

Utilizamos los métodos aquí presentados para evaluar cómo longevos animales con menor IIS modulan la agregación de proteínas dependientes de la edad. Por Western blot (vea el paso 2.2, rápida extracción de la proteína insoluble para el análisis de Western blot), analizamos el total y el contenido de proteína insoluble de jóvenes (día 3 de la edad adulta) y de gusanos (día 18 de la edad adulta) control de RNAi y de ARNi a la insulina / Receptor de IGF-1-como daf-2. Ob...

Watch this Scientific Journal Video about Methods to Study Changes in Inherent Protein Aggregation with Age in Caenorhabditis elegans at JoVE.com

Methods to Study Changes in Inherent Protein Aggregation with Age in Caenorhabditis elegans

Métodos de estudio cambios de agregación inherente de proteína con la edad en Caenorhabditis elegans

El método presentado aquí pretende explorar la agregación de proteínas durante el envejecimiento normal en el organismo modelo Caenorhabditis elegans. El protocolo representa una poderosa herramienta para el estudio de los agregados grandes altamente insolubles que se forman con la edad y determinar cómo cambios en proteostasis impactan de agregación de la proteína.

In the last decades, the prevalence of neurodegenerative disorders, such as Alzheimer's disease (AD) and Parkinson's disease (PD), has grown. These ...

methods-to-study-changes-inherent-protein-aggregation-with-age

Universidad de Cartagena UDEC

Research

JoVE Journal

Biology

Methods to Study Changes in Inherent Protein Aggregation with Age in Caenorhabditis elegans

8.4K vistas.  German Center for Neurodegenerative Diseases (DZNE). El método presentado aquí pretende explorar la agregación de proteínas durante el envejecimiento normal en el organismo modelo Caenorhabditis elegans. El protocolo representa una poderosa herramienta para el estudio de los agregados grandes altamente insolubles que se forman con la edad y determinar cómo cambios en proteostasis impactan de agregación de la proteína.

Video: Methods to Study Changes in Inherent Protein Aggregation with Age in Caenorhabditis elegans

Solid Plate-based Dietary Restriction in Caenorhabditis elegans

Reduction of food intake without malnutrition or starvation is known to increase lifespan and delay the onset of various age-related diseases in a wide range of species, including mammals. It also causes a decrease in body weight and fertility, as well as lower levels of plasma glucose, insulin, and IGF-1 in these animals. This treatment is often referred to as dietary restriction (DR) or caloric restriction (CR). The nematode Caenorhabditis elegans has emerged as an important model organism for studying the biology of aging. Both environmental and genetic manipulations have been used to model DR and have shown to extend lifespan in C. elegans. However, many of the reported DR studies in C. elegans were done by propagating animals in liquid media, while most of the genetic studies in the aging field were done on the standard solid agar in petri plates. Here we present a DR protocol using standard solid NGM agar-based plate with killed bacteria.

Solid Plate-based Dietary Restriction in Caenorhabditis elegans

Here we present a protocol for performing solid plate-based dietary restriction in C. elegans with killed bacteria.

Placa Sólida basado en la restricción dietética Caenorhabditis elegans</em

Reduction of food intake without malnutrition or starvation is known to increase lifespan and delay the onset of various age-related diseases in a wide ...

Investigación

Biología

Time-lapse Microscopy of Early Embryogenesis in Caenorhabditis elegans

Caenorhabditis elegans has often been used as a model system in studies of early developmental processes. The transparency of the 
embryos, the genetic resources, and the relative ease of transformation are qualities that make C. elegans an excellent model for early embryogenesis. Laser-based 
confocal microscopy and fluorescently labeled tags allow researchers to follow specific cellular structures and proteins in the developing embryo. For example, 
one can follow specific organelles, such as lysosomes or mitochondria, using fluorescently labeled dyes. These dyes can be delivered to the early embryo by means 
of microinjection into the adult gonad. Also, the localization of specific proteins can be followed using fluorescent protein tags. Examples are presented here 
demonstrating the use of a fluorescent lysosomal dye as well as fluorescently tagged histone and ubiquitin proteins. The labeled histone is used to visualize 
the DNA and thus identify the stage of the cell cycle. GFP-tagged ubiquitin reveals the dynamics of ubiquitinated vesicles in the early embryo. Observations 
of labeled lysosomes and GFP:: ubiquitin can be used to determine if there is colocalization between ubiquitinated vesicles and lysosomes. A technique for 
the microinjection of the lysosomal dye is presented. Techniques for generating transgenenic strains are presented elsewhere (1, 2). For imaging, embryos 
are cut out of adult hermaphrodite nematodes and mounted onto 2% agarose pads followed by time-lapse microscopy on a standard laser scanning confocal 
microscope or a spinning disk confocal microscope. This methodology provides for the high resolution visualization of early embryogenesis.

Time-lapse Microscopy of Early Embryogenesis in Caenorhabditis elegans

This article describes a technique for the visualization of the early events of embryogenesis in the nematode Caenorhabditis elegans.

Time-lapse microscopía de embriogénesis temprana en Caenorhabditis elegans

Caenorhabditis elegans has often been used as a model system in studies of early developmental processes.  The transparency of the 
embryos, the genetic ...

Basic Caenorhabditis elegans Methods: Synchronization and Observation

Research into the molecular and developmental biology of the nematode Caenorhabditis elegans was begun in the early seventies by Sydney Brenner and it has since been used extensively as a model organism 1. C. elegans possesses key attributes such as simplicity, transparency and short life cycle that have made it a suitable experimental system for fundamental biological studies for many years 2. Discoveries in this nematode have broad implications because many cellular and molecular processes that control animal development are evolutionary conserved 3.
C. elegans life cycle goes through an embryonic stage and four larval stages before animals reach adulthood. Development can take 2 to 4 days depending on the temperature. In each of the stages several characteristic traits can be observed. The knowledge of its complete cell lineage 4,5 together with the deep annotation of its genome turn this nematode into a great model in fields as diverse as the neurobiology 6, aging 7,8, stem cell biology 9 and germ line biology 10. 
An additional feature that makes C. elegans an attractive model to work with is the possibility of obtaining populations of worms synchronized at a specific stage through a relatively easy protocol. The ease of maintaining and propagating this nematode added to the possibility of synchronization provide a powerful tool to obtain large amounts of worms, which can be used for a wide variety of small or high-throughput experiments such as RNAi screens, microarrays, massive sequencing, immunoblot or in situ hybridization, among others. 
Because of its transparency, C. elegans structures can be distinguished under the microscope using Differential Interference Contrast microscopy, also known as Nomarski microscopy. The use of a fluorescent DNA binder, DAPI (4',6-diamidino-2-phenylindole), for instance, can lead to the specific identification and localization of individual cells, as well as subcellular structures/defects associated to them.

Basic Caenorhabditis elegans Methods: Synchronization and Observation

The easiness of maintaining and propagating the nematode C. elegans make it a nice model organism to work with. The possibility of synchronizing worms allows the work with a significant amount of subjects at the same developmental stage, what facilitates the study of one particular process in many animals.

Básico<em&gt; Caenorhabditis elegans</em&gt; Métodos de sincronización y de observación

Research into the molecular and developmental biology of the nematode Caenorhabditis elegans was begun in the early seventies by Sydney Brenner and it has ...

4D Imaging of Protein Aggregation in Live Cells

One of the key tasks of any living cell is maintaining the proper folding of newly synthesized proteins in the face of ever-changing environmental conditions and an intracellular environment that is tightly packed, sticky, and hazardous to protein stability1. The ability to dynamically balance protein production, folding and degradation demands highly-specialized quality control machinery, whose absolute necessity is observed best when it malfunctions. Diseases such as ALS, Alzheimer's, Parkinson's, and certain forms of Cystic Fibrosis have a direct link to protein folding quality control components2, and therefore future therapeutic development requires a basic understanding of underlying processes. Our experimental challenge is to understand how cells integrate damage signals and mount responses that are tailored to diverse circumstances.
The primary reason why protein misfolding represents an existential threat to the cell is the propensity of incorrectly folded proteins to aggregate, thus causing a global perturbation of the crowded and delicate intracellular folding environment1. The folding health, or "proteostasis," of the cellular proteome is maintained, even under the duress of aging, stress and oxidative damage, by the coordinated action of different mechanistic units in an elaborate quality control system3,4. A specialized machinery of molecular chaperones can bind non-native polypeptides and promote their folding into the native state1, target them for degradation by the ubiquitin-proteasome system5, or direct them to protective aggregation inclusions6-9.
In eukaryotes, the cytosolic aggregation quality control load is partitioned between two compartments8-10: the juxtanuclear quality control compartment (JUNQ) and the insoluble protein deposit (IPOD) (Figure 1 - model). Proteins that are ubiquitinated by the protein folding quality control machinery are delivered to the JUNQ, where they are processed for degradation by the proteasome. Misfolded proteins that are not ubiquitinated are diverted to the IPOD, where they are actively aggregated in a protective compartment.
Up until this point, the methodological paradigm of live-cell fluorescence microscopy has largely been to label proteins and track their locations in the cell at specific time-points and usually in two dimensions. As new technologies have begun to grant experimenters unprecedented access to the submicron scale in living cells, the dynamic architecture of the cytosol has come into view as a challenging new frontier for experimental characterization. We present a method for rapidly monitoring the 3D spatial distributions of multiple fluorescently labeled proteins in the yeast cytosol over time. 3D timelapse (4D imaging) is not merely a technical challenge; rather, it also facilitates a dramatic shift in the conceptual framework used to analyze cellular structure.
We utilize a cytosolic folding sensor protein in live yeast to visualize distinct fates for misfolded proteins in cellular aggregation quality control, using rapid 4D fluorescent imaging. The temperature sensitive mutant of the Ubc9 protein10-12 (Ubc9ts) is extremely effective both as a sensor of cellular proteostasis, and a physiological model for tracking aggregation quality control. As with most ts proteins, Ubc9ts is fully folded and functional at permissive temperatures due to active cellular chaperones. Above 30 &deg;C, or when the cell faces misfolding stress, Ubc9ts misfolds and follows the fate of a native globular protein that has been misfolded due to mutation, heat denaturation, or oxidative damage. By fusing it to GFP or other fluorophores, it can be tracked in 3D as it forms Stress Foci, or is directed to JUNQ or IPOD.

Cellular viability depends on timely and efficient management of protein misfolding. Here we describe a method for visualizing the different potential fates of a misfolded protein: refolding, degradation, or sequestration in inclusions. We demonstrate the use of a folding sensor, Ubc9ts, for monitoring proteostasis and aggregation quality control in live cells using 4D microscopy.

4D de imágenes de la agregación de proteínas en células vivas

One of the key tasks of any living cell is maintaining the proper folding of newly synthesized proteins in the face of ever-changing environmental ...

Prostaglandin Extraction and Analysis in Caenorhabditis elegans

Caenorhabditis elegans is emerging as a powerful animal model to study the biology of lipids1-9. Prostaglandins are an important class of eicosanoids, which are lipid signals derived from polyunsaturated fatty acids (PUFAs)10-14. These signalling molecules are difficult to study because of their low abundance and reactive nature. The characteristic feature of prostaglandins is a cyclopentane ring structure located within the fatty acid backbone. In mammals, prostaglandins can be formed through cyclooxygenase enzyme-dependent and -independent pathways10,15. C. elegans synthesizes a wide array of prostaglandins independent of cyclooxygenases6,16,17. A large class of F-series prostaglandins has been identified, but the study of eicosanoids is at an early stage with ample room for new discoveries. Here we describe a procedure for extracting and analyzing prostaglandins and other eicosanoids. Charged lipids are extracted from mass worm cultures using a liquid-liquid extraction technique and analyzed by liquid chromatography coupled to electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). The inclusion of deuterated analogs of prostaglandins, such as PGF2 &alpha;-d4 as an internal standard is recommended for quantitative analysis. Multiple reaction monitoring or MRM can be used to quantify and compare specific prostaglandin types between wild-type and mutant animals. Collision-induced decomposition or MS/MS can be used to obtain information on important structural features. Liquid chromatography mass spectrometry (LC-MS) survey scans of a selected mass range, such as m/z 315-360 can be used to evaluate global changes in prostaglandin levels. We provide examples of all three analyses. These methods will provide researchers with a toolset for discovering novel eicosanoids and delineating their metabolic pathways.

Prostaglandin Extraction and Analysis in Caenorhabditis elegans

In this paper, we describe an optimized procedure for extracting and analyzing prostaglandins and other eicosanoids from C. elegans using LC-MS/MS.

Extracción y análisis de prostaglandina en<em&gt; Caenorhabditis elegans</em

Caenorhabditis elegans is emerging as a powerful animal model to study the biology of lipids1-9. Prostaglandins are an important class of eicosanoids, ...

Using Caenorhabditis elegans as a Model System to Study Protein Homeostasis in a Multicellular Organism

The folding and assembly of proteins is essential for protein function, the long-term health of the cell, and longevity of the organism. Historically, the function and regulation of protein folding was studied in vitro, in isolated tissue culture cells and in unicellular organisms. Recent studies have uncovered links between protein homeostasis (proteostasis), metabolism, development, aging, and temperature-sensing. These findings have led to the development of new tools for monitoring protein folding in the model metazoan organism Caenorhabditis elegans. In our laboratory, we combine behavioral assays, imaging and biochemical approaches using temperature-sensitive or naturally occurring metastable proteins as sensors of the folding environment to monitor protein misfolding. Behavioral assays that are associated with the misfolding of a specific protein provide a simple and powerful readout for protein folding, allowing for the fast screening of genes and conditions that modulate folding. Likewise, such misfolding can be associated with protein mislocalization in the cell. Monitoring protein localization can, therefore, highlight changes in cellular folding capacity occurring in different tissues, at various stages of development and in the face of changing conditions. Finally, using biochemical tools ex vivo, we can directly monitor protein stability and conformation. Thus, by combining behavioral assays, imaging and biochemical techniques, we are able to monitor protein misfolding at the resolution of the organism, the cell, and the protein, respectively.

Using Caenorhabditis elegans as a Model System to Study Protein Homeostasis in a Multicellular Organism

To study the relationship between protein homeostasis, stress and aging, we monitored changes in protein folding by following protein dysfunction, protein localization in the cell and protein stability at the organismal, cellular and protein levels, using the genetically tractable metazoan Caenorhabditis elegans as a model system.

The folding and assembly of proteins is essential for protein function, the long-term health of the cell, and longevity of the organism. Historically, the ...

In Vitro Aggregation Assays Using Hyperphosphorylated Tau Protein

Alzheimer's disease is one of a large group of neurodegenerative disorders known as tauopathies that are manifested by the neuronal deposits of hyperphosphorylated tau protein in the form of neurofibrillary tangles (NFTs). The density of NFT correlates well with cognitive impairment and other neurodegenerative symptoms, thus prompting the endeavor of developing tau aggregation-based therapeutics. Thus far, however, tau aggregation assays use recombinant or synthetic tau that is devoid of the pathology-related phosphorylation marks. Here we describe two assays using recombinant, hyperphosphorylated tau as the subject. These assays can be scaled up for high-throughput screens for compounds that can modulate the kinetics or stability of hyperphosphorylated tau aggregates. Novel therapeutics for Alzheimer's disease and other tauopathies can potentially be discovered using hyperphosphorylated tau isoforms.

In Vitro Aggregation Assays Using Hyperphosphorylated Tau Protein

Unmodified and hyperphosphorylated tau proteins were used in two in vitro aggregation assays to reveal the hyperphosphorylation-dependent fast aggregation kinetics. These assays pave the way for future screens for compounds that can modulate the propensity of hyperphosphorylated tau to form fibrils that underlie the progression of Alzheimer&#8217;s disease.

En Vitro agregación ensayos usando hiperfosforilada proteína tau

Alzheimer's disease is one of a large group of neurodegenerative disorders known as tauopathies that are manifested by the neuronal deposits of ...

Cultivation of Caenorhabditis elegans in Three Dimensions in the Laboratory

The use of genetic model organisms such as Caenorhabditis elegans has led to seminal discoveries in biology over the last five decades. Most of what we know about C. elegans is limited to laboratory cultivation of the nematodes that may not necessarily reflect the environments they normally inhabit in nature. Cultivation of C. elegans in a 3D habitat that is more similar to the 3D matrix that worms encounter in rotten fruits and vegetative compost in nature could reveal novel phenotypes and behaviors not observed in 2D. In addition, experiments in 3D can address how phenotypes we observe in 2D are relevant for the worm in nature. Here, a new method in which C. elegans grows and reproduces normally in three dimensions is presented. Cultivation of C. elegans in Nematode Growth Tube-3D (NGT-3D) can allow us to measure the reproductive fitness of C. elegans strains or different conditions in a 3D environment. We also present a novel method, termed Nematode Growth Bottle-3D (NGB-3D), to cultivate C. elegans in 3D for microscopic analysis. These methods allow scientists to study C. elegans biology in conditions that are more reflective of the environments they encounter in nature. These can help us to understand the overlying evolutionary relevance of the physiology and behavior of C. elegans we observe in the laboratory.

Cultivation of Caenorhabditis elegans in Three Dimensions in the Laboratory

We present a simple method to construct 3D nematode cultivation systems called NGT-3D and NGB-3D. These can be used to study nematode fitness and behaviors in habitats that are more similar to natural Caenorhabditis elegans habitats than the standard 2D laboratory C. elegans culture plates.

El cultivo de<em&gt; Caenorhabditis elegans</em&gt; En tres dimensiones en el Laboratorio

The use of genetic model organisms such as Caenorhabditis elegans has led to seminal discoveries in biology over the last five decades. Most of what we ...

Combined Nucleotide and Protein Extractions in Caenorhabditis elegans

A single biological sample holds a plethora of information, and it is now common practice to simultaneously investigate several macromolecules to capture a full picture of the multiple levels of molecular processing and changes between different conditions. This protocol presents the method of isolating DNA, RNA, and protein from the same sample of the nematode Caenorhabditis elegans to remove the variation introduced when these biomolecules are isolated from replicates of similarly treated but ultimately different samples. Nucleic acids and protein are extracted from the nematode using the acid guanidinium thiocyanate-phenol-chloroform extraction method, with subsequent precipitation, washing, and solubilization of each. We show the successful isolation of RNA, DNA, and protein from a single sample from three strains of nematode and HeLa cells, with better protein isolation results in adult animals. Additionally, guanidinium thiocyanate-phenol-chloroform-extracted protein from nematodes improves the resolution of larger proteins, with enhanced detectable levels as observed by immunoblotting, compared to the traditional RIPA extraction of protein.
The method presented here is useful when investigating samples using a multiomic approach, specifically for the exploration of the proteome and transcriptome. Techniques that simultaneously assess multiomics are appealing because molecular signaling underlying complex biological phenomena is thought to occur at complementary levels; however, it has become increasingly common to see that changes in mRNA levels do not always reflect the same change in protein levels and that the time of collection is relevant in the context of circadian regulations. This method removes any intersample variation when assaying different contents within the same sample (intrasample.)

Combined Nucleotide and Protein Extractions in Caenorhabditis elegans

Here, we present a protocol for the isolation of RNA, DNA, and protein from the same sample, in an effort to reduce variation, improve reproducibility, and facilitate interpretations.

Nucleótido y extracciones de proteínas de Caenorhabditis elegans

A single biological sample holds a plethora of information, and it is now common practice to simultaneously investigate several macromolecules to capture ...

Quantifying Tissue-Specific Proteostatic Decline in Caenorhabditis elegans

The ability to maintain proper function and folding of the proteome (protein homeostasis) declines during normal aging, facilitating the onset of a growing number of age-associated diseases. For instance, proteins with polyglutamine expansions are prone to aggregation, as exemplified with the huntingtin protein and concomitant onset of Huntington&#8217;s disease. The age-associated deterioration of the proteome has been widely studied through the use of transgenic Caenorhabditis elegans expressing polyQ repeats fused to a yellow fluorescent protein (YFP). This polyQ::YFP transgenic animal model facilitates the direct quantification of the age-associated decline of the proteome through imaging the progressive formation of fluorescent foci (i.e., protein aggregates) and subsequent onset of locomotion defects that develop as a result of the collapse of the proteome. Further, the expression of the polyQ::YFP transgene can be driven by tissue-specific promoters, allowing the assessment of proteostasis across tissues in the context of an intact multicellular organism. This model is highly amenable to genetic analysis, thus providing an approach to quantify aging that is complementary to lifespan assays. We describe how to accurately measure polyQ::YFP foci formation within either neurons or body wall muscle during aging, and the subsequent onset of behavioral defects. Next, we highlight how these approaches can be adapted for higher throughput, and potential future applications using other emerging strategies for C. elegans genetic analysis.

Quantifying Tissue-Specific Proteostatic Decline in Caenorhabditis elegans

Proteostatic decline is a hallmark of aging, facilitating the onset of neurodegenerative diseases. We outline a protocol to quantifiably measure proteostasis in two different Caenorhabditis elegans tissues through heterologous expression of polyglutamine repeats fused to a fluorescent reporter. This model allows rapid in vivo genetic analysis of proteostasis.

Cuantificación de la disminución proteostática específica del tejido en Caenorhabditis elegans

The ability to maintain proper function and folding of the proteome (protein homeostasis) declines during normal aging, facilitating the onset of a ...

Métodos de estudio cambios de agregación inherente de proteína con la edad en Caenorhabditis elegans

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