Biz eleştirel deneysel değerlendirme ve tartışma için UIC de O&#39;Bryan laboratuvar teşekkür ederim. Klinik ve Translasyonel Bilimler Hibe UL1TR000050 için UIC Merkezi - Bu çalışma Translational Bilim ilerlemek için GKC ve Ulusal Merkezi Amerikan Kalp Derneği Hibe 11SDG5230003 tarafından desteklenmiştir.

1. Hücre transfeksiyonu <ol><li> Transfeksiyon önce plaka hücreleri gün, immünofloresan için daha az hücre kaplama. <ol><li> Immunofloresan için: 6-plaka, kat cam kapak fişleri içinde (1 de başına) en az 4 saat süreyle 37 ° C de% 0.02 jelatin ile, orta ile bir kez yıkayın ve her bir kuyu için, plaka 1 x 10 5 HEK 293T 2 ml tam Hücreler büyüme ortamı içinde [Dulbecco&#39;nun modifiye edilmiş Eagle ortamı (DMEM) artı% 10 FBS]. </li><li> Akış sitometrik ve Western blot analizi için: levha 1,2 5 HEK 293T hücre / oyuk 6-plaka (24-çukurlu plaka başına 0,5 ml tam büyüme ortamı içinde 0.3 x 10 5 HEK 293T hücreleri içinde 2 ml tam büyüme ortamı x 10 .) </li></ol></li><li> Imalatçının protokolüne göre transfeksiyon için DNA hazırlayın: Effectene (Qiagen) immünofloresan için kullanılır. Transit-LT1 (Mirus) akım sitometrik ve Western Blot analizleri için kullanılır. Kullanılan DNA miktarı aşağıda listelenmiştir. <table border="1"><tbody><tr><td&gt; </td><td> 24 oyuklu plaka (ng) </td><td> 6-plaka (ng) </td></tr><tr><td> CFP-vektör </td><td> 10 </td><td> 50 </td></tr><tr><td> VN N-AKAP-Lbc </td><td> 200 </td><td> 1.000 </td></tr><tr><td> VC N-PDE4D3-FL (tam boy PDE4D3) </td><td> 2.5, 5, 10, 20, 40, 80 </td><td> 100 </td></tr><tr><td> VC N-PDE4D3-UCR1 (UCR1 etki alanı içeren bir PDE4D3 N-terminal parçası) </td><td></td><td> 100 </td></tr><tr><td> VC N-PDE4D3-UCR2 + CAT (UCR2 ve katalitik etki içeren bir PDE4D3 C-terminal parçası) </td><td></td><td> 100 </td></tr></tbody></table> Transfeksiyon Effectene (6-de) kullanılarak: <ol><li> Oda sıcaklığında 5 dakika boyunca belirtilen plazmid DNA + miktarı 4 ul artırıcı 100 ul tampon EM için, karışım, ve inkübe ekleyin. </li><li> 10 dakika boyunca 5 ul Effectene, karışım, ve inkübe eklemeoda sıcaklığı. Ekle hücrelere bırak-bilge. </li></ol> : Transit-LT1 (6-well/24-well) kullanarak transfeksiyon <ol><li> Bir steril tüp içine Opti-MEM I serumsuz ortamda 250 μl/50 ul plasmid DNA Belirtilen miktarlarda ekleyin. </li><li> Seyreltilmiş DNA karışıma Transit-LT1 reaktif ekleyin ve karıştırmak için hafifçe pipetle. (Transit-LT1 Reaktif: DNA oranı DNA 1 mikrogram başına Transit-LT1 reaktif 3 ul). </li><li> Oda sıcaklığında 30 dakika süreyle inkübe edilir ve hücreleri damla damla ilave edin. </li></ol></li></ol> 2. Sitometrisi, Western Blot, ve İmmünofloresan için Hücre Hazırlık <ol><li> 24 saat sonrası transfeksiyon, hücreler hasat öncesi Epifloresans mikroskop altında floresan kontrol edin. </li><li> Akım sitometri analizi için hücre hazırlama: <ol><li> 24-well/6-well plakaları ile, 0.5 ml / 2 ml buz gibi soğuk PBS ile bir hücreleri yıkayın. </li><li> 50 μl/250 ul% 0.05 tripsin kullanarak hücreleri ayırmak. </li><li> 200 ul / 1 ml DMEM ortamı ile nötralize tripsin. </li><li> Co5 dakika boyunca 500 x g&#39;de santrifüj ile llect 250 ul hücreleri (her ikisi de 24 oyuklu ve 6-delikli plaka için), Western blot analizi için geriye kalan hücreler (1 mi) kullanın. </li><li> 250 ul FACS buffer içinde yeniden süspanse hücreleri [PBS +% 0.5 (w / v) BSA, 2 mM EDTA +] akış sitometri analizi için buz üzerinde depolar. Akım sitometri analizi hemen olmayacak eğer hücreler (PBS içinde)% 1 paraformaldehid sabitlenebilir. </li></ol></li><li> Western Blot analizi için hücre hazırlama: akım sitometri analizi için hücre hazırlama paralel olarak gerçekleştirdi. <ol><li> 2 ml buz gibi soğuk PBS ile yıkayın 1x hücreleri, hücre parçalama tamponu 100 ul [10 mM sodyum fosfat tamponu, pH 6.95, 150 mM NaCI, 5 mM EDTA, 5 mM EGTA,% 1 Triton X-100] eklenerek hücre parçalandığı . </li><li> 4 de 21.000 xg&#39;de 10 dakika boyunca santrifüj ile hücre lizatı toplamak ° C </li><li> , Bradford protein testi ile protein konsantrasyonu ölçmek SDS-PAGE için şerit başına protein eşit miktarda yük ve immün için nitroselüloz transfer. </li></ol&gt; </li><li> Immünofloresan için hücre hazırlama. <ol><li> 2 ml PBS ile durulayın 3x hücreler, oda sıcaklığında 10 dakika boyunca% 3.7 paraformaldehid (PBS) 1 ml hücre düzeltmek için, daha sonra 5 dakika boyunca 2 ml PBS ile 3 kez yıka. </li><li> Montaj orta kullanarak, bir cam slayt üzerinde kayma kapağı monte edin. Gerekirse oje kullanarak lamel kenarları mühür. </li><li> Muayene ° C önce 4 de slaytlar saklayın. </li></ol></li></ol> 3. Akım Sitometri ve İmmünofloresan Mikroskopi <ol><li> Flow sitometri bir Beckman Coulter Mavi 488 nm ile donatılmış ADP, 405 nm ve 642 nm katı hal lazerleri kullanılarak yapılır. Zirve yazılım satın alma ve analiz için kullanılır. <ol><li> Standart boncuklar kullanarak akış sitometresinin kalibre. </li><li> Yolluk canlı hücre popülasyonu için doğrusal bir ölçekte Arsa İleri dağılım (FSC) / yana dağılım (SSC). </li><li> Yolluk olmayan toplu canlı hücre popülasyonu için arsa gerilim / FSC darbe genişliği. </li><li> Arsa count/FL6 (OBP fluorescencyolluk olmayan toplu canlı CFP-pozitif hücreler için bir günlük ölçekte e, 405 nm). </li><li> BiFC yoğunluğu için bir günlük ölçekte Arsa count/FL1 (YFP floresan, 488 nm). </li><li> FSC, SSC, FL1 ve FL6 fotoğraf çoğaltıcı tüp (PMT) Her bir sinyal için eşik ayarlamak için voltaj ayarlamak, YFP-CFP-çift negatif örnekleri çalıştırın. </li><li> Run (hem YFP + ve CFP +) için örnekler gelecek off-line tazminat pozitif ve tek </li><li> Analiz için en azından 10,000 kapılı olayları (olmayan toplanan canlı CFP + hücreleri) elde edin. </li></ol></li><li> . İmmünofloresan mikroskobu bir Zeiss LSM 510 konfokal mikroskop Not kullanılarak yapılır: tüm ayarlar arasında tutarlı (örneğin, zum, iğne deliği, dedektör kazanç, amplifikatör ofset, çerçeve boyutu, tarama hızı, tarama ortalama ve lazer güç olarak) tutmak önemlidir tüm verilerin uygun bir karşılaştırma için örnekler. </li></ol> 4. Veri Analizi (Summit Yazılımı kullanarak Yapılan) <ol><li> Acquisit için olana benzer bir analiz protokolü ayarlamauygun yolluk ile iyon: Canlı hücreler için FSC / SSC nokta arsa Gate 1. Olmayan toplu canlı hücreler için Gate 1 FSC / darbe genişliği Kapısı 2. Olmayan toplu OBP + canlı hücreler için Gate 3 sayısı / CFP Gate 3. </li><li> YFP ve YFP + ve OBP + tek pozitif hücreleri kullanarak OBP sinyal telafi. </li><li> CFP / YFP pozitif hücreler için yeniden belirlemek kesme hatları. </li><li> İhracat YFP CFP floresan yoğunluğu (MFI) + veri komplo için Excel&#39;e hücreler anlamına gelir. </li><li> AKAP-Lbc, PDE4D3 ifade seviyelerine YFP MFI Normale ve Western blot tarafından belirlenen, α-tubulin yükleme kontrolü. </li></ol>

<ol>
	<li>Collura, V., Boissy, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=From+protein-protein+complexes+to+interactomics.">From protein-protein complexes to interactomics.</a> Subcell Biochem. 43, 135-183 (2007).</li><li>Stumpf, M. 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=Estimating+the+size+of+the+human+interactome.">Estimating the size of the human interactome.</a> Proc. Natl. Acad. Sci. U.S.A. 105, 6959-6964 (2008).</li><li>Shekhawat, S. S., Ghosh, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Split-protein+systems:+beyond+binary+protein-protein+interactions.">Split-protein systems: beyond binary protein-protein interactions.</a> Curr. Opin. Chem. Biol. 15, 789-797 (2011).</li><li>Dwane, S., Kiely, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tools+used+to+study+how+protein+complexes+are+assembled+in+signaling+cascades.">Tools used to study how protein complexes are assembled in signaling cascades.</a> Bioeng. Bugs. 2, 247-259 (2011).</li><li>Piehler, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+methodologies+for+measuring+protein+interactions+in+vivo+and+in+vitro.">New methodologies for measuring protein interactions in vivo and in vitro.</a> Curr. Opin. Struct. Biol. 15, 4-14 (2005).</li><li>Kerppola, T. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+and+implementation+of+bimolecular+fluorescence+complementation+(BiFC)+assays+for+the+visualization+of+protein+interactions+in+living+cells.">Design and implementation of bimolecular fluorescence complementation (BiFC) assays for the visualization of protein interactions in living cells.</a> Nat. Protoc. 1, 1278-1286 (2006).</li><li>Shyu, Y. J., Suarez, C. D., Hu, C. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visualization+of+ternary+complexes+in+living+cells+by+using+a+BiFC-based+FRET+assay.">Visualization of ternary complexes in living cells by using a BiFC-based FRET assay.</a> Nat. Protoc. 3, 1693-1702 (2008).</li><li>Wong, K. A., O'Bryan, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bimolecular+fluorescence+complementation.">Bimolecular fluorescence complementation.</a> J. Vis. Exp. (50), e2643 (2011).</li><li>Sugarbaker, E. V., Thornthwaite, J. T., Temple, W. T., Ketcham, A. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flow+cytometry:+general+principles+and+applications+to+selected+studies+in+tumor+biology.">Flow cytometry: general principles and applications to selected studies in tumor biology.</a> Int. Adv. Surg. Oncol. 2, 125-153 (1979).</li><li>Koshy, S., Alizadeh, P., Timchenko, L. T., Beeton, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+measurement+of+GLUT4+translocation+to+the+plasma+membrane+by+flow+cytometry.">Quantitative measurement of GLUT4 translocation to the plasma membrane by flow cytometry.</a> J. Vis. Exp. (45), e2429 (2010).</li><li>Smith, C. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Basic+confocal+microscopy.">Basic confocal microscopy.</a> Curr. Protoc. Mol. Biol. Chapter 14 (Unit 14), 11 (2008).</li><li>Westwick, J. K., Lamerdin, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improving+drug+discovery+with+contextual+assays+and+cellular+systems+analysis.">Improving drug discovery with contextual assays and cellular systems analysis.</a> Methods Mol. Biol. 756, 61-73 (2011).</li><li>Kilpatrick, L. E., Holliday, N. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dissecting+the+pharmacology+of+G+protein-coupled+receptor+signaling+complexes+using+bimolecular+fluorescence+complementation.">Dissecting the pharmacology of G protein-coupled receptor signaling complexes using bimolecular fluorescence complementation.</a> Methods Mol. Biol. 897, 109-138 (2012).</li></ol>

Yazarlar hiçbir rakip mali çıkarlarının olmadığını beyan ederim.

BiFC protein-protein etkileşimleri incelemek için basit ve hassas bir yöntemdir. Bu yöntem, yeni bir protein-protein etkileşimleri tanımlamak için kullanılamaz, ancak, bu hücre içinde, protein-protein etkileşimi teyit etmek için ve fonksiyonel özelliklerini incelemek için özellikle uygundur, örneğin protein-protein etkileşimi siteleri eşleme protein kompleksleri hücre altı konumlanması olarak, ve protein-protein etkileşimi modüle eden küçük moleküller / peptitlerin taranması için. VN ve VC ...

650.000 protein-protein etkileşimleri, normal hücre fonksiyonlarını 1,2 korunmasında kritik rol oynayan, insan interactome var olduğu tahmin edilmektedir. Ortak immunoprecipitation yanı sıra (eş-IP), altın standart (PCA) hücreleri 3 içinde protein-protein etkileşimleri tespit duyarlılığını artırmak için geliştirilmiştir, hücre lizat birkaç protein parçası tamamlama deneyleri protein-protein etkileşimleri incelemek için. Teknikleri Förster rezonans enerji transferi (FRET), Biyoparlaklık Rezonans Enerji Transferi (BRET) ve Bimoleküler Floresan tamamlama (BiFC) 4,5 içerir. Her potansiyel bir etkileşim protein ortağı (bu örnekte biz AKAP-Lbc ve PDE4D3 kullanın) sigortalarla, BiFC bir floresan protein iki parça (bir YFP varyant burada Venüs kullanın) kolaylaştırdı dernek dayanmaktadır. F tarafından görüntülenmiştir olabilir fonksiyonel floresan hücreleri sonuçları içinde ilgi iki protein, etkileşimiCanlı veya sabit hücreleri 6,7,8 kullanarak luorescence mikroskobu. Diğer PCA ile karşılaştırıldığında, BiFC canlı hücrelerde hücresel yerleşimi çalışma potansiyeli olan, duyarlı ve daha az teknik zordur. Bu tekniğin büyük bir dezavantajı, ancak bir kere oluştuktan sonra, floresan protein kompleksi geri alınamaz olmasıdır. Bu nedenle dinamik protein-protein etkileşimleri incelemek için iyi bir yöntem değildir. Bu yazıda, Venüs floresan yoğunlukları izleyerek AKAP-Lbc ile PDE4D3 etkileşimi siteleri eşleştirmek için BiFC kullanın. (Otomatik yüksek kapasiteli makineler kullanılarak gerçekleştirilmiştir değilse) zaman alıcı ve emek-yoğun floresan mikroskobu kullanarak geleneksel analizi ile karşılaştırıldığında, akım sitometri, kısa bir süre 9 üzerinde heterojen nüfus hücrelerin binlerce basit bir kantitatif analiz sağlar 10. Burada, akış sitometrik-BiFC analizi ve ortak IP geleneksel bir yan-yana karşılaştırma yaparak, biz göstermek bu iki methods karşılaştırılabilir veri sağlamak, ancak, akış sitometrik BiFC analizi zaman alıcı az ve ilgi hücreleri sınırlı zaman daha yararlı olabilir daha az malzeme kullanır.

<table border="1">
	<tbody>
		<tr>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>REAGENTS</td>
		</tr>
		<tr>
			<td>Dulbecco's modified Eagle's media (DMEM)</td>
			<td>Invitrogen</td>
			<td>11965-092</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Penicilin-Streptomycin (pen/strep), 100x</td>
			<td>Invitrogen</td>
			<td>15070-063</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum (FBS)</td>
			<td>Invitrogen</td>
			<td>16000-044</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Anti-Flag antibody</td>
			<td>Sigma</td>
			<td>M2, F1804</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Anti-HA antibody</td>
			<td>Covance</td>
			<td>16B12, MMS-101R</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>&alpha;-tubulin</td>
			<td>Sigma</td>
			<td>DM1A, T9026</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Anti-GFP antibody</td>
			<td>Clontech</td>
			<td>632569</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Cell culture plates, 6-well tissue culture treated</td>
			<td>Thermo Fisher Scientific</td>
			<td>130184</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>HEK 293T cells</td>
			<td>ATCC</td>
			<td>CRL-11268</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Maxiprep plasmid purification kit, high speed</td>
			<td>Qiagen</td>
			<td>12663</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Dulbecco's Phosphate-buffered saline (DPBS), sterile 1x</td>
			<td>Invitrogen</td>
			<td>14190-144</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Trypsin-EDTA, 0.05% (w/v)</td>
			<td>Gibco</td>
			<td>25300</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Polystyrene round-bottom tubes for FACS staining</td>
			<td>BD Biosciences</td>
			<td>352052</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Paraformaldehyde</td>
			<td>Fisher Scientific</td>
			<td>S74337MF</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Prolong gold antifade reagent with DAPI</td>
			<td>Invitrogen</td>
			<td>P-36931</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Superfrost plus Microscope slides</td>
			<td>Fisher Scientific</td>
			<td>12-550-15</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Fisherfinest premium cover glass</td>
			<td>Fisher Scientific</td>
			<td>12-548-5P</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>EQUIPMENT</td>
		</tr>
		<tr>
			<td>CO2 air-jacketed Incubator</td>
			<td>NuAIR DH autoflow</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Confocal microscope LSM510 META</td>
			<td>Carl Zeiss, Inc</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Electrophoresis and transfer unit</td>
			<td>Biorad</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Cyan ADP Flow Cytometer</td>
			<td>Beckman Coulter</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
	</tbody>
</table>

flow cytometric analysis of bimolecular fluorescence complementation: a high throughput quantitative method to study protein-protein interaction

Hücrelerin içinde protein-protein etkileşimleri incelemek için yöntemler arasında, Bimoleküler Floresan tamamlama (BiFC) oldukça basit ve hassastır. BiFC bir floresan protein olmayan iki floresan parçalarının (venüs, bir sarı floresan protein varyantı, burada kullanılan) kullanılarak floresan üretimi esas alınmaktadır. Floresan olmayan Venüs parçaları (VN ve VC) bağlı VN-AKAP-Lbc-VC-PDE4D3 etkileşim ve fonksiyonel bir floresan protein oluşumu için floresan verecek şekilde iki etkileşen proteinleri (bu durumda, AKAP-Lbc ve PDE4D3) kaynaşmıştır hücrelerin içinde. BiFC protein komplekslerinin hücre altı konumlanması ve floresan yoğunluğuna dayalı protein etkileşimleri gücü hakkında bilgi sağlar. Bununla birlikte, protein-protein etkileşimi kuvvetini ölçmek için mikroskopi kullanılarak BiFC analizi zaman alıcı ve protein ekspresyonu ve etkileşim içinde heterojenite nedeniyle biraz görecelidir. Sitometrik akış kaplinBiFC metodolojisi ile analizi, floresan BiFC protein-protein etkileşimi sinyalini doğru olarak kısa bir süre içinde hücrelerin büyük bir miktar için ölçülebilir. Burada, AKAP-Lbc ile etkileşim için gerekli olan PDE4D3 bölgeleri eşleştirmek için bu metodolojinin bir uygulama göstermektedir. Bu yüksek kapasiteli yöntem, protein-protein etkileşimleri düzenleyen tarama faktörlere uygulanabilir.

AKAP-Lbc ve PDE4D3 yapıları (Şekil 1B) sırasıyla, VN ve VC parçaları erimiş edildi. AKAP-Lbc ve fonksiyonel YFP floresan (Şekil 1A) içinde PDE4D3 sonuç etkileşimi. Burada PDE4D3 içinde haritası AKAP-Lbc bağlayıcı sitelere BiFC yöntemini kullanın. Memba korunmuş bölge 1 (UCR1), yukarı korunmuş bölge 2 (UCR2) ve katalitik bölgesi (CAT) PDE4D3 bağlama sitesi tarama için kullanılan bu nedenle, tam boy (FL), UCR1 ve UCR2 artı CAT, PDE4 aile proteinler arasında k...

Watch this Scientific Journal Video about Flow Cytometric Analysis of Bimolecular Fluorescence Complementation: A High Throughput Quantitative Method to Study Protein-protein Interaction at JoVE.com

Flow Cytometric Analysis of Bimolecular Fluorescence Complementation: A High Throughput Quantitative Method to Study Protein-protein Interaction

Bimoleküler Floresan tamamlama akış sitometrik analizi protein-protein etkileşimleri incelemek için bir yüksek kapasiteli nicel yöntem sağlar. Bu metodoloji, eşleme protein bağlama siteleri ve protein-protein etkileşimleri düzenleyen faktörler taranması için uygulanabilir.

Bimoleküler Floresan tamamlama akışı Sitometrik Analizi: Protein-protein etkileşim Eğitim Bir Yüksek Verimli Kantitatif Yöntemi

Among methods to study protein-protein interaction inside cells, Bimolecular Fluorescence Complementation (BiFC) is relatively simple and sensitive. BiFC ...

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Research

JoVE Journal

Biology

18.3K Görüntüleme.  University of Illinois at Chicago. Bimoleküler Floresan tamamlama akış sitometrik analizi protein-protein etkileşimleri incelemek için bir yüksek kapasiteli nicel yöntem sağlar. Bu metodoloji, eşleme protein bağlama siteleri ve protein-protein etkileşimleri düzenleyen faktörler taranması için uygulanabilir.

Video: Flow Cytometric Analysis of Bimolecular Fluorescence Complementation: A High Throughput Quantitative Method to Study Protein-protein Interaction

A Neuronal and Astrocyte Co-Culture Assay for High Content Analysis of Neurotoxicity

High Content Analysis (HCA) assays combine cells and detection reagents with automated imaging and powerful image analysis algorithms, allowing measurement of multiple cellular phenotypes within a single assay. In this study, we utilized HCA to develop a novel assay for neurotoxicity. Neurotoxicity assessment represents an important part of drug safety evaluation, as well as being a significant focus of environmental protection efforts. Additionally, neurotoxicity is also a well-accepted in vitro marker of the development of neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. Recently, the application of HCA to neuronal screening has been reported. By labeling neuronal cells with &beta;III-tubulin, HCA assays can provide high-throughput, non-subjective, quantitative measurements of parameters such as neuronal number, neurite count and neurite length, all of which can indicate neurotoxic effects. However, the role of astrocytes remains unexplored in these models. Astrocytes have an integral role in the maintenance of central nervous system (CNS) homeostasis, and are associated with both neuroprotection and neurodegradation when they are activated in response to toxic substances or disease states. GFAP is an intermediate filament protein expressed predominantly in the astrocytes of the CNS. Astrocytic activation (gliosis) leads to the upregulation of GFAP, commonly accompanied by astrocyte proliferation and hypertrophy. This process of reactive gliosis has been proposed as an early marker of damage to the nervous system. The traditional method for GFAP quantitation is by immunoassay. This approach is limited by an inability to provide information on cellular localization, morphology and cell number. We determined that HCA could be used to overcome these limitations and to simultaneously measure multiple features associated with gliosis - changes in GFAP expression, astrocyte hypertrophy, and astrocyte proliferation - within a single assay. In co-culture studies, astrocytes have been shown to protect neurons against several types of toxic insult and to critically influence neuronal survival. Recent studies have suggested that the use of astrocytes in an in vitro neurotoxicity test system may prove more relevant to human CNS structure and function than neuronal cells alone. Accordingly, we have developed an HCA assay for co-culture of neurons and astrocytes, comprised of protocols and validated, target-specific detection reagents for profiling &beta;III-tubulin and glial fibrillary acidic protein (GFAP). This assay enables simultaneous analysis of neurotoxicity, neurite outgrowth, gliosis, neuronal and astrocytic morphology and neuronal and astrocytic development in a wide variety of cellular models, representing a novel, non-subjective, high-throughput assay for neurotoxicity assessment. The assay holds great potential for enhanced detection of neurotoxicity and improved productivity in neuroscience research and drug discovery.

This article describes a novel protocol and reagent set designed for sensitive measurement of neurotoxic effects of compounds and treatments on co-cultures of neurons and astrocytes using high content analysis. Results demonstrate that high content analysis represents an exciting novel technology for neurotoxicity assessment.

Nörotoksisite Yüksek İçerik Analizi Nöronal ve Astrosit Hücre Co-Kültür Testi

High Content Analysis (HCA) assays combine cells and detection reagents with automated imaging and powerful image analysis algorithms, allowing ...

Biyoloji

A high-throughput method to globally study the organelle morphology in S. cerevisiae

High-throughput methods to examine protein localization or organelle morphology is an effective tool for studying protein interactions and can help achieve an comprehensive understanding of molecular pathways. In Saccharomyces cerevisiae, with the development of the non-essential gene deletion array, we can globally study the morphology of different organelles like the endoplasmic reticulum (ER) and the mitochondria using GFP (or variant)-markers in different gene backgrounds. However, incorporating GFP markers in each single mutant individually is a labor-intensive process. Here, we describe a procedure that is routinely used in our laboratory. By using a robotic system to handle high-density yeast arrays and drug selection techniques, we can significantly shorten the time required and improve reproducibility. In brief, we cross a GFP-tagged mitochondrial marker (Apc1-GFP) to a high-density array of 4,672 nonessential gene deletion mutants by robotic replica pinning.  Through diploid selection, sporulation, germination and dual marker selection, we recover both alleles. As a result, each haploid single mutant contains Apc1-GFP incorporated at its genomic locus. Now, we can study the morphology of mitochondria in all non-essential mutant background. Using this high-throughput approach, we can conveniently study and delineate the pathways and genes involved in the inheritance and the formation of organelles in a genome-wide setting.

GFP-fusion proteins are widely used to visualize organelles by confocal microscopy. However, screening for mutations that affect the morphology of organelles generally requires individual mutagenesis and is time consuming. Here, we demonstrate a method to simultaneously incorporate organelle-GFP markers in almost 5,000 non-essential genes in yeast.

S. cerevisiae &quot;adlı organel morfolojisi küresel çalışma yüksek verimli bir yöntem

High-throughput methods to examine protein localization or organelle morphology is an effective tool for studying protein interactions and can help ...

Bimolecular Fluorescence Complementation (BiFC) Assay for Protein-Protein Interaction in Onion Cells Using the Helios Gene Gun

Investigation of gene function in diverse organisms relies on knowledge of how the gene products interact with each other in their normal cellular environment. The Bimolecular Fluorescence Complementation (BiFC) Assay1 allows researchers to visualize protein-protein interactions in living cells and has become an essential research tool. This assay is based on the facilitated association of two fragments of a fluorescent protein (GFP) that are each fused to a potential interacting protein partner. The interaction of the two protein partners would facilitate the association of the N-terminal and C-terminal fragment of GFP, leading to fluorescence. For plant researchers, onion epidermal cells are an ideal experimental system for conducting the BiFC assay because of the ease in obtaining and preparing onion tissues and the direct visualization of fluorescence with minimal background fluorescence. The Helios Gene Gun (BioRad) is commonly used for bombarding plasmid DNA into onion cells. We demonstrate the use of Helios Gene Gun to introduce plasmid constructs for two interacting Arabidopsis thaliana transcription factors, SEUSS (SEU) and LEUNIG HOMOLOG (LUH)2 and the visualization of their interactions mediated by BiFC in onion epidermal cells.

Bimolecular Fluorescence Complementation BiFC Assay for Protein-Protein Interaction in Onion Cells Using the Helios Gene Gun

This article illustrates how to properly use the BioRad Helios Gene Gun to introduce plasmid DNA into onion epidermal cells and how to test for protein-protein interactions in onion cells based on the principle of Bimolecular Fluorescence Complementation (BiFC)

Helios Gen Tabancası kullanarak Soğan Hücrelerde Protein-Protein Etkileşimi Bimoleküler Floresan tamamlama (BiFC) Testi

Investigation of gene function in diverse organisms relies on knowledge of how the gene products interact with each other in their normal cellular ...

Quantification of dsDNA using the Hitachi F-7000 Fluorescence Spectrophotometer and PicoGreen Dye

Quantification of DNA, especially in small concentrations, is an important task with a wide range of biological applications including standard molecular biology assays such as synthesis and purification of DNA, diagnostic applications such as quantification of DNA amplification products, and detection of DNA molecules in drug preparations. During this video we will demonstrate the capability of the Hitachi F-7000 Fluorescence Spectrophotometer equipped with a Micro Plate Reader accessory to perform dsDNA quantification using Molecular Probes Quant-it PicoGreen dye reagent kit.
The F-7000 Fluorescence Spectrophotometer offers high sensitivity and high speed measurements. It is a highly flexible system capable of measuring fluorescence, luminescence, and phosphorescence. Several measuring modes are available, including wavelength scan, time scan, photometry and 3-D scan measurement. The spectrophotometer has sensitivity in the range of 50 picomoles of fluorescein when using a 300 &#956;L sample volume in the microplate, and is capable of measuring scan speeds of 60,000 nm/minute. It also has a wide dynamic range of up to 5 orders of magnitude which allows for the use of calibration curves over a wide range of concentrations. The optical system uses all reflective optics for maximum energy and sensitivity. The standard wavelength range is 200 to 750 nm, and can be extended to 900 nm when using one of the optional near infrared photomultipliers. The system allows optional temperature control for the plate reader from 5 to 60 degrees Celsius using an optional external temperature controlled liquid circulator. The microplate reader allows for the use of 96 well microplates, and the measuring speed for 96 wells is less than 60 seconds when using the kinetics mode.
Software controls for the F-7000 and Microplate Reader are also highly flexible. Samples may be set in either column or row formats, and any combination of wells may be chosen for sample measurements. This allows for optimal utilization of the microplate. Additionally, the software allows importing micro plate sample configurations created in Excel and saved in comma separated values, or "csv" format. Microplate measuring configurations can be saved and recalled by the software for convenience and increased productivity. Data results can be output to a standard report, to Excel, or to an optional Report Generator Program.

Demonstration of quantification of dsDNA using Molecular Probes PicoGreen dye and Hitachi F-7000 Fluorescence Spectrophotometer equipped with a microplate reader accessory.

Hitachi F-7000 Floresans Spektrofotometre ve PicoGreen Boya kullanarak dsDNA Niceleme

Quantification of DNA, especially in small concentrations, is an important task with a wide range of biological applications including standard molecular ...

Bimolecular Fluorescence Complementation

Defining the subcellular distribution of signaling complexes is imperative to understanding the output from that complex. Conventional methods such as immunoprecipitation do not provide information on the spatial localization of complexes. In contrast, BiFC monitors the interaction and subcellular compartmentalization of protein complexes. In this method, a fluororescent protein is split into amino- and carboxy-terminal non-fluorescent fragments which are then fused to two proteins of interest. Interaction of the proteins results in reconstitution of the fluorophore (Figure 1)1,2. A limitation of BiFC is that once the fragmented fluorophore is reconstituted the complex is irreversible3. This limitation is advantageous in detecting transient or weak interactions, but precludes a kinetic analysis of complex dynamics. An additional caveat is that the reconstituted flourophore requires 30min to mature and fluoresce, again precluding the observation of real time interactions4. BiFC is a specific example of the protein fragment complementation assay (PCA) which employs reporter proteins such as green fluorescent protein variants (BiFC), dihydrofolate reductase, b-lactamase, and luciferase to measure protein:protein interactions5,6. Alternative methods to study protein:protein interactions in cells include fluorescence co-localization and F&ouml;rster resonance energy transfer (FRET)7. For co-localization, two proteins are individually tagged either directly with a fluorophore or by indirect immunofluorescence. However, this approach leads to high background of non-interacting proteins making it difficult to interpret co-localization data. In addition, due to the limits of resolution of confocal microscopy, two proteins may appear co-localized without necessarily interacting. With BiFC, fluorescence is only observed when the two proteins of interest interact. FRET is another excellent method for studying protein:protein interactions, but can be technically challenging. FRET experiments require the donor and acceptor to be of similar brightness and stoichiometry in the cell. In addition, one must account for bleed through of the donor into the acceptor channel and vice versa. Unlike FRET, BiFC has little background fluorescence, little post processing of image data, does not require high overexpression, and can detect weak or transient interactions. Bioluminescence resonance energy transfer (BRET) is a method similar to FRET except the donor is an enzyme (e.g. luciferase) that catalyzes a substrate to become bioluminescent thereby exciting an acceptor. BRET lacks the technical problems of bleed through and high background fluorescence but lacks the ability to provide spatial information due to the lack of substrate localization to specific compartments8. Overall, BiFC is an excellent method for visualizing subcellular localization of protein complexes to gain insight into compartmentalized signaling.

The subcellular localization of proteins is important in determining the spatio-temporal regulation of cell signaling. Here, we describe bimolecular fluorescence complementation (BiFC) as a straightforward method for monitoring the spatial interactions of proteins in the cell.

Bimoleküler Floresan tamamlama

Defining the subcellular distribution of signaling complexes is imperative to understanding the output from that complex. Conventional methods such as ...

Detection of Protein Interactions in Plant using a Gateway Compatible Bimolecular Fluorescence Complementation (BiFC) System

We have developed a BiFC technique to test the interaction between two proteins in vivo. This is accomplished by splitting a yellow fluorescent protein (YFP) into two non-overlapping fragments. Each fragment is cloned in-frame to a gene of interest. These constructs can then be co-transformed into Nicotiana benthamiana via Agrobacterium mediated transformation, allowing the transit expression of fusion proteins. The reconstitution of YFP signal only occurs when the inquest proteins interact 1-7. To test and validate the protein-protein interactions, BiFC can be used together with yeast two hybrid (Y2H) assay. This may detect indirect interactions which can be overlooked in the Y2H. Gateway technology is a universal platform that enables researchers to shuttle the gene of interest (GOI) into as many expression and functional analysis systems as possible8,9. Both the orientation and reading frame can be maintained without using restriction enzymes or ligation to make expression-ready clones. As a result, one can eliminate all the re-sequencing steps to ensure consistent results throughout the experiments. We have created a series of Gateway compatible BiFC and Y2H vectors which provide researchers with easy-to-use tools to perform both BiFC and Y2H assays10. Here, we demonstrate the ease of using our BiFC system to test protein-protein interactions in N. benthamiana plants.

Detection of Protein Interactions in Plant using a Gateway Compatible Bimolecular Fluorescence Complementation BiFC System

We have developed a technique to test protein-protein interactions in plant. A yellow fluorescent protein (YFP) is split into two non-overlapping fragments. Each fragment is cloned in-frame to a gene of interest via Gateway system, enabling expression of fusion proteins. Reconstitution of YFP signal only occurs when the inquest proteins interact.

Ağ Geçidi Uyumlu Bimoleküler Floresan tamamlama (BiFC) kullanarak Bitki Protein Etkileşimleri Tespiti

We have developed a BiFC technique to test the interaction between two proteins in vivo. This is accomplished by splitting a yellow fluorescent protein ...

A Liquid Phase Affinity Capture Assay Using Magnetic Beads to Study Protein-Protein Interaction: The Poliovirus-Nanobody Example

In this article, a simple, quantitative, liquid phase affinity capture assay is presented. Provided that one protein can be tagged and another protein labeled, this method can be implemented for the investigation of protein-protein interactions. It is based on one hand on the recognition of the tagged protein by cobalt coated magnetic beads and on the other hand on the interaction between the tagged protein and a second specific protein that is labeled. First, the labeled and tagged proteins are mixed and incubated at room temperature. The magnetic beads, that recognize the tag, are added and the bound fraction of labeled protein is separated from the unbound fraction using magnets. The amount of labeled protein that is captured can be determined in an indirect way by measuring the signal of the labeled protein remained in the unbound fraction. The described liquid phase affinity assay is extremely useful when conformational conversion sensitive proteins are assayed. The development and application of the assay is demonstrated for the interaction between poliovirus and poliovirus recognizing nanobodies1. Since poliovirus is sensitive to conformational conversion2 when attached to a solid surface (unpublished results), the use of ELISA is limited and a liquid phase based system should therefore be preferred. An example of a liquid phase based system often used in polioresearch3,4 is the micro protein A-immunoprecipitation test5. Even though this test has proven its applicability, it requires an Fc-structure, which is absent in the nanobodies6,7. However, as another opportunity, these interesting and stable single-domain antibodies8 can be easily engineered with different tags. The widely used (His)6-tag shows affinity for bivalent ions such as nickel or cobalt, which can on their turn be easily coated on magnetic beads. We therefore developed this simple quantitative affinity capture assay based on cobalt coated magnetic beads. Poliovirus was labeled with 35S to enable unhindered interaction with the nanobodies and to make a quantitative detection feasible. The method is easy to perform and can be established with a low cost, which is further supported by the possibility of effectively regenerating the magnetic beads.

In this article, a simple, quantitative, liquid phase affinity capture assay is presented. It is a reliable technique based on the interaction between magnetic beads and tagged proteins (e.g. nanobodies) on one hand and the affinity between the tagged protein and a second, labeled protein (e.g. poliovirus) on the other.

Protein-Protein Etkileşimi Okumak Manyetik Boncuk Kullanarak Bir Sıvı Faz Affinity Yakalama Testi: Poliovirüs-Nanobody Örnek

In this article, a simple, quantitative, liquid phase affinity capture assay is presented. Provided that one protein can be tagged and another protein ...

Quantitative Analysis of Autophagy using Advanced 3D Fluorescence Microscopy

Prostate cancer is the leading form of malignancies among men in the U.S. While surgery carries a significant risk of impotence and incontinence, traditional chemotherapeutic approaches have been largely unsuccessful. Hormone therapy is effective at early stage, but often fails with the eventual development of hormone-refractory tumors. We have been interested in developing therapeutics targeting specific metabolic deficiency of tumor cells. We recently showed that prostate tumor cells specifically lack an enzyme (argininosuccinate synthase, or ASS) involved in the synthesis of the amino acid arginine1. This condition causes the tumor cells to become dependent on exogenous arginine, and they undergo metabolic stress when free arginine is depleted by arginine deiminase (ADI)1,10. Indeed, we have shown that human prostate cancer cells CWR22Rv1 are effectively killed by ADI with caspase-independent apoptosis and aggressive autophagy (or macroautophagy)1,2,3. Autophagy is an evolutionarily-conserved process that allows cells to metabolize unwanted proteins by lysosomal breakdown during nutritional starvation4,5. Although the essential components of this pathway are well-characterized6,7,8,9, many aspects of the molecular mechanism are still unclear - in particular, what is the role of autophagy in the death-response of prostate cancer cells after ADI treatment? In order to address this question, we required an experimental method to measure the level and extent of autophagic response in cells - and since there are no known molecular markers that can accurately track this process, we chose to develop an imaging-based approach, using quantitative 3D fluorescence microscopy11,12.
Using CWR22Rv1 cells specifically-labeled with fluorescent probes for autophagosomes and lysosomes, we show that 3D image stacks acquired with either widefield deconvolution microscopy (and later, with super-resolution, structured-illumination microscopy) can clearly capture the early stages of autophagy induction. With commercially available digital image analysis applications, we can readily obtain statistical information about autophagosome and lysosome number, size, distribution, and degree of colocalization from any imaged cell. This information allows us to precisely track the progress of autophagy in living cells and enables our continued investigation into the role of autophagy in cancer chemotherapy.

Autophagy is a ubiquitous process that enables cells to degrade and recycle proteins and organelles. We apply advanced fluorescence microscopy to visualize and quantify the small, but essential, physical changes associated with the induction of autophagy, including the formation and distribution of autophagosomes and lysosomes, and their fusion into autolysosomes.

Gelişmiş 3D Floresan Mikroskobu kullanılarak Otofaji Kantitatif Analiz

Prostate cancer is the leading form of malignancies among men in the U.S. While surgery carries a significant risk of impotence and incontinence, ...

A High Throughput MHC II Binding Assay for Quantitative Analysis of Peptide Epitopes

Biochemical assays with recombinant human MHC II molecules can provide rapid, quantitative insights into immunogenic epitope identification, deletion, or design1,2. Here, a peptide-MHC II binding assay is scaled to 384-well format. The scaled down protocol reduces reagent costs by 75% and is higher throughput than previously described 96-well protocols1,3-5. Specifically, the experimental design permits robust and reproducible analysis of up to 15 peptides against one MHC II allele per 384-well ELISA plate. Using a single liquid handling robot, this method allows one researcher to analyze approximately ninety test peptides in triplicate over a range of eight concentrations and four MHC II allele types in less than 48 hr. Others working in the fields of protein deimmunization or vaccine design and development may find the protocol to be useful in facilitating their own work. In particular, the step-by-step instructions and the visual format of JoVE should allow other users to quickly and easily establish this methodology in their own labs.

Biochemical assays with recombinant human MHC II molecules can provide rapid, quantitative insights into immunogenic epitope identification, deletion, or design. &#160;Here, a peptide-MHC II binding assay scaled to 384-well plates is described. This cost effective format should prove useful in the fields of protein deimmunization and vaccine design and development.

Peptid Epitopların Kantitatif Analiz için bir yüksek veri akışı MHC II Bağlanma Deneyi

Biochemical assays with recombinant human MHC II molecules can provide rapid, quantitative insights into immunogenic epitope identification, deletion, or ...

Protein-protein Interactions Visualized by Bimolecular Fluorescence Complementation in Tobacco Protoplasts and Leaves

Many proteins interact transiently with other proteins or are integrated into multi-protein complexes to perform their biological function. Bimolecular fluorescence complementation (BiFC) is an in vivo method to monitor such interactions in plant cells. In the presented protocol the investigated candidate proteins are fused to complementary halves of fluorescent proteins and the respective constructs are introduced into plant cells via agrobacterium-mediated transformation. Subsequently, the proteins are transiently expressed in tobacco leaves and the restored fluorescent signals can be detected with a confocal laser scanning microscope in the intact cells. This allows not only visualization of the interaction itself, but also the subcellular localization of the protein complexes can be determined. For this purpose, marker genes containing a fluorescent tag can be coexpressed along with the BiFC constructs, thus visualizing cellular structures such as the endoplasmic reticulum, mitochondria, the Golgi apparatus or the plasma membrane. The fluorescent signal can be monitored either directly in epidermal leaf cells or in single protoplasts, which can be easily isolated from the transformed tobacco leaves. BiFC is ideally suited to study protein-protein interactions in their natural surroundings within the living cell. However, it has to be considered that the expression has to be driven by strong promoters and that the interaction partners are modified due to fusion of the relatively large fluorescence tags, which might interfere with the interaction mechanism. Nevertheless, BiFC is an excellent complementary approach to other commonly applied methods investigating protein-protein interactions, such as coimmunoprecipitation, in vitro pull-down assays or yeast-two-hybrid experiments.

Formation of protein complexes in vivo can be visualized by bimolecular fluorescence complementation. Interaction partners are fused to complementary parts of fluorescent tags and transiently expressed in tobacco leaves, resulting in a reconstituted fluorescent signal upon close proximity of the two proteins.

Tütün protoplastlarında ve Yapraklar Bimoleküler Floresan tamamlama tarafından Visualized protein-protein etkileşimleri

Many proteins interact transiently with other proteins or are integrated into multi-protein complexes to perform their biological function. Bimolecular ...