NIH / NİDA DA034783 tarafından desteklenir. Biz multimeir-PAGE ile teknik yardım için Bryan A. Killinger teşekkür ederim.

1. Doku Hazırlanması <ol><li> 4x BN-PAGE numune tampon maddesi (200 mM Bis (2-hidroksietil) amino-tris (hidroksimetil) metan (Bis-Tris), 200 mM NaCI,% 40 a / h gliserol,% 0.004 Ponceau S, pH 7.2, 10 mL hazırlanması ). NOT: Bu stok solüsyon önceden yapılmış ve 4 ° C&#39;de saklanabilir. </li><li> 1x ticari proteaz inhibitörü kokteyli içeren 750 uL dH 2 O 4x numune tamponu 250 uL seyreltin. Girdap ve buz üzerinde soğuk. </li><li> Temiz bir Dounce homojenleştirici 30 vuruş 1 mL 1x buz soğukluğunda BN-PAGE numune tampon maddesi içinde, hedef doku, 20 mg homojenize edilir. NOT: Bu gösteri deneme için, hedef doku bütün sıçan beyni dokudur. Homojenleştirmeden sonra, numuneler çözünür ve zar proteinlerinin elektroforezi izin vermek üzere hafif bir deterjan gibi% 2 digitonin ile muamele edilebilir. </li><li> 30 dakika çözünmeyen hücre içeriği: pelet 14,000 x g&#39;de bir 1.5 mL mikrosantrifüj tüpüne Homojenat, ve santrifüj aktarın. AfteR santrifüj, buz üzerinde temiz bir tüp içine süpernatant süzün. </li><li> bisinkoninik asit (BCA) ya da benzer protein kantitatif analizi kullanılarak Üst faz, protein konsantrasyonunu ölçmek için üretici talimatları takip edin. </li><li> Homojenat örnek (ler) deterjan ihtiva ise,% 0.25 Coomassie için homojenat çözüm getirmek için yeterli bir sulu çözelti içinde% 5, Coomassie Mavi G-250, bir miktar ilave edin. </li></ol> 2. BN-PAGE <ol><li> 25 ml 20x mavi yerli seyreltin (BN) içine tampon stok (1.0 M Bis-Tris, 1.0 M Trişin, pH 6.8) elektroforez 475 ml dH 1x çalışan tampon 500 mL olmak üzere% 0.002 Coomassie Blue ihtiva eden 2 O. <ol><li> Numuneler deterjan ihtiva bunun yerine% 0.02 Coomassie içeren 1x çalışan tampon 250 mL ve hiçbiri içeren başka bir 250 mL olun. </li></ol></li><li> 4 ° C&#39;ye soğutma tamponu (ler). </li><li> Temizleyin ve üretici talimatlarına göre kaset dökme bir poliakrilamid jel toplayın. </li><li&gt; Bir standart tarif 7&#39;ye göre BN poliakrilamid jeli (% 3, T istifleme katman,% 6, T çözme tabakası) dökün ve iyi tarak. </li><li> Jeller polimerize sonra, DH 2 O ile kaseti yıkayın ve üretici talimatlarına göre elektroforez aygıtı monte edin. </li><li> Kuyucuklu bir tarak çıkarın ve 1x BN-PAGE çalışma tamponu ile kuyu doldurun. Numuneler yüklenene kadar tampon ile bütün iç odasının doldurulması kaçının. <ol><li> Numuneler deterjan ihtiva ise,% 0.02 Coomassie Blue içeren tampon ile kuyu doldurun. NOT: 4 ° C&#39;de adımları 2.7-2.9 gerçekleştirin. </li></ol></li><li> Jel yükleme ipuçları kullanarak, arzu edilen kuyulara proteinin 20 ug içeren homojenat bir hacim pipetle. kullanılmayan herhangi bir kuyulara 1x BN-PAGE numune tampon maddesi eşdeğer bir hacmi Pipet. Not: eklemek için homojenat uygun hacmi hesaplamak için bir BCA aracıyla tespit protein konsantrasyonunu kullanmakuyu. </li><li> Örnekler yüklendikten sonra, 1 x BN-PAGE çalışma tamponu ile iç bölmeyi doldurmak. Jel tamamen tampon altında olduğundan emin olun. Daha sonra, üretici tarafından belirtilen seviyeye 1x çalışma tamponu ile dış oda doldurun. <ol><li> Numuneler deterjan ihtiva ise,% 0.02 Coomassie mavisi içeren 1 x tampon ve boya içermeyen 1x çalışan tamponu ile dış hücre iç bölmeyi doldurmak. </li></ol></li><li> güç kaynağına Elektrotlar ve boya bant katmanı çözme içine ~ 2 cm ilerler kadar 150 V&#39;de jelde proteinleri Electrophorese. Dur ve güç kaynağını kesin. </li></ol> 3. Çapraz bağlanma NOT: 4 ° C&#39;de Adımları 3.1-3.6&#39;da gerçekleştirin. <ol><li> elektroforez aygıtı sökün ve jel kasetinin cam levhaların ayrılması. Çıkarın ve yığma tabakasını atın. </li><li> Dikkatle boya ön alt kenarının altında jel kesti. almakBu kesim olarak yumuşak ve düz bir şekilde mümkün kılmak için bakım ve daha sonra jel kullanılmamış parça atılır. Bu homojenat, numunedeki tüm protein içerecektir geniş bir ~ 2 cm, poliakrilamid jel yatay şerit bırakacaktır. </li><li> Jel şeridin kenarları boyunca kullanılmamış herhangi bir kısmı Trim. </li><li> Dikkatli bir şekilde küçük bir kap içinde 10 ml fosfat tamponlu salin (PBS) içine şerit yerleştirin, yavaşça dengelenmeye 30 dakika nutation karıştırın. </li><li> Dengelemeden sonra, atmak ve başka bir 10 mL PBS ile değiştirin. Pipet 500 uL 25 mM DSP PBS içine dimetil sülfoksit içerisinde çözündürüldü ve 30 dakika boyunca, yukarıdaki (aşama 3.4) karıştırın. </li><li> DSP çözümü kapalı dökün. Reaksiyona girmemiş DSP gidermek için% 2 sodyum dodesil sülfat (SDS) içeren 0.375 M tris (hidroksimetil) aminometan hidroklorür (tris-HCl), pH 8.8, 10 ml ekleyin. 15 dakika üğrüm devam edin. </li></ol> 4. SDS-PAGE <ol><li> Jel şerit söndürme iken, SDS-PA hazırlanmasıStandart yöntemler 9&#39;a göre GE jel çözeltileri. Polimerizasyon reaktif eklemeyin. </li><li> Söndürüldükten sonra, oda sıcaklığına kadar ΒΝ jel şeridi dönmek ve yeni bir jel kasetine şerit dökme. <ol><li> Bunu yapmak için, dikkatle jel alıp temiz bir jel kaset boşluk tabağa yerleştirin. </li><li> Orient boya ön alt yani BN-PAGE sırasında en uzak tarafında yeni bir kaset üstüne yakın gereken yeni kasetinin üst (en yakın olan ve şerit, jel şeridi, önceden gelen çevrilmiş olmalıdır oryantasyon). Şekil 3&#39;e bakınız. </li><li> Üst kenarı da kapak plakasının üst kenarı olacak burada ile yer alacağı şekilde şerit yerleştirin (yani, yeni bir jel üstünde olacaktır). boya ön cam levha yatay kenarlarına paralel olduğundan emin olun. </li><li> t yer bırakarak ara duvarların birine karşı kesilmiş şeridin bir yan itinjel o diğer tarafı dökülecek ve bir protein standardı veya merdiven yüklenmesine olanak sağlamaktadır. </li><li> Jel bandın alt kenarı bir tırtıklı veya alanlar varsa, dikkatli bir şekilde kesilmiş. Eğer mevcut ise, bunlar jel sırasında tuzak kabarcıklar dökme olacaktır. </li><li> Jel şerit doğru bir biçimde pozisyonlandığı zaman, ara plaka üzerinde kapak plakası yerleştirin. sıkışan hava kabarcıklarını dışarı itmek için hafif bir baskı uygulayın. </li><li> Üretici talimatlarına göre jel-dökme aygıtı monte devam edin. </li></ol></li><li> çözündürücü jel tamponuna polimerizasyon reaktifleri ekleyin ve serolojik bir pipet kullanarak hazırlanan jel kaset içine dökün. istif tabakası için oda bırakmak için, kesilmiş BN-PAGE jel şeridin altında yaklaşık 2 cm jel kaseti doldurun. </li><li> döküldü jel üst üzerinde 100 uL butanol ekleyin ve çözme tabakasının polimerizasyonu için 30 dakika izin verir. butonalün kapalı dökün. </li><li> Istifleme jeli çözeltisine polimerizasyon reaktifleri ekleyin. Bir serolog kullanmaik pipet, jel kasetinde kalan boş alanı doldurmak için istifleme tabaka dökülür. <ol><li> bu jel bir şeridin altında alanı doldurur ve hava kabarcıklarının değildir bu nedenle yığın tabaka dökülür gibi jel kaseti yatırın. </li><li> istifleme jeli tamponu jel şeridin altında boş alanı doldurur, giderek düzeyde bir taban üzerine jel kaseti döndürür. </li><li> yaklaşık taşmaları o kadar bir sonraki istifleme jeli tamponu ile kesilmiş jel şerit boş alanı doldurmak için devam edin. </li></ol></li><li> istifleme tabaka 30 dakika boyunca polimerize olmaya bırakın. Not: jel polimerize ise 10 x SDS-PAGE çalışma tamponu (250 mM tris (hidroksimetil) aminometan (tris), 1.9 M glisin,% 1 SDS) konur. Bu aynı zamanda önceden yapılmış ve oda sıcaklığında saklanabilir. </li><li> 1x çalışma tamponu yapmak için 450 ml dH 2 O içine 50 ml 10X SDS-PAGE çalışma tamponu stokunu. </li><li> istifleme tabaka polimerize sonra, dökme elde edilen jel kaseti çıkarmakcihaz, dH 2 O ile durulayın ve üretici talimatlarına göre elektroforez aygıtı monte edin. </li><li> Bundan sonra, imalatçı tarafından belirtilen seviyeye dış bölmeyi doldurmak, 1 x SDS-PAGE çalışma tamponu ile tamamen iç bölme doldurun. </li><li> Bir sonraki bir molekül ağırlığı merdiven ya da uygun protein standardı ile kesilmiş jel şeride yer yükleyin. </li><li> güç kaynağına elektrotları takın ve Coomassie boyası jel kapalı çalışır zaman 120 V&#39;ta örnekleri Electrophorese, dur ve güç kaynağı ayırın. </li><li> 10 bağlayıcı antikor tarafından elektrobeneklenme ile ve protein saptaması standart yöntemler kullanılarak jel analiz edin. </li></ol>

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Yazarlar ifşa hiçbir şey yok.

Protein-protein etkileşimleri canlılar yürütmek her görev için önemlidir. Bu nedenle, bunlar yoğun inceleme ve araştırma konusudur. Multimer-PAGE yakalama ayrılması ve protein kompleksleri çok çeşitli analiz etmek için bir yeni yöntemdir. Daha önce hastalıkla bağlantılı protein α-sinüklein 11 oligimerization okuyan uygulanabilirliğini ortaya koymuştur. Şekil 2&#39;de gösterildiği gibi Bununla birlikte, pek çok protein kompleksleri için uzatılabilir...

<html> Normal hücre fonksiyonlarını protein-protein etkileşimleri, 1, 2 bağlıdır. Bunun bir sonucu olarak, insan hastalıkları genellikle çeşitli protein kompleksleri 3 montajı ve davranış düzensizlik tarafından işaretlenir. Böyle etkileşimleri karakterize yeteneği dolayısıyla çok önemlidir. Bu etkileşimlerin tespit Mevcut araçları genellikle etkileşim ortakları çekme-aşağı ve ardından hedef proteinler, saflaştırılmasını gerektirir. Geleneksel saflaştırma diferansiyel santrifüj, çökeltme ve / veya kromatografi 4 ile gerçekleştirilir. Bu yöntemler zaman alıcıdır, her bir hedef protein için değiştirilmesi gerekir, ve genellikle düşük verimlerle sonuçlanabilir. Modern saflaştırma yöntemleri, bir yakalama molekülü 5 bağlanmış boncuklarıyla yüklenmiş sütunlar üzerinde bağışıklık çökeltmesi ya da ekstre proteinleri hedef peptid etiketleri kaynaşmasını içerenBu, bir çok proteinin şekilde uzatılabilir da &quot;&gt; 6., Potansiyel olarak her zamanki bağlanma partnerleri için afinite açısından farklılık yapılarda ortaya çıkan hedef sekansı, bir modifikasyonunu gerektirir. Bazı protein-protein etkileşimleri, hassas doğası, bu yöntem uygulanabilir olmayabilir demektir birçok senaryolara. Ayrıca, protein-protein etkileşimleri eşleştirmek için kullanılan açılan tahliller nedeniyle özgürlük ve yem proteinin yerli olmayan seviyelerinin kısıtlı derecelerde, doğru bir hücresel resim toplayamaz. İdeal olarak, protein kompleksleri saflaştırma veya çekme aşağı gerek kalmadan, doğal hallerine tespit edilebilir. Mavi doğal poliakrilamid jel elektroforezi (BN-PAGE), sodyum dodesil sülfat poliakrilamid jel elektroforezi (SDS-PAGE) için daha az denatüre alternatif olarak geliştirilen ve biyolojik örnekler 7 bazı proteinler ve komplekslerin ayrılması için izin veriliyordu. Bununla birlikte, BN-PAGE&#39;de proteinler lar göre ayırmakdiğer moleküllerle boyut, yük ve üç boyutlu yapı ve birlikte dahil olmak üzere değişkenlerin ge sayısı. Bu faktörlerin etkileşimler genellikle proteinlerin eş ayrılması, agregat oluşumu ve kötü protein bandı çözünürlüğü ile sonuçlanır. İki boyutlu yerli-poliakrilamid jel elektroforezi bu sorunların 8, hepsi bir giderir, ama. Doğal ayrılması ile ortaya çıkan komplikasyonları aşmak için, bazı yazarlar, doku lysate&#39;lerin 4 protein kompleksleri yakalamak için bu ditiyobis (süksinimidil propionat) gibi amin-reaktif çapraz bağlama reaktifleri, (DSP) kullanır. Bu muamele edilmiş Lizatlar daha sonra denatüre edilmiş ve protein kompleksleri doğal boyutu ve makyaj korurken, SDS-PAGE ile ayrılabilir. çapraz bağlama reaktifleri, doku lizatlarında başka bir molekülün yakınlığı ve proteinlere dayalı tepki Bununla birlikte, çok serbestlik derecelerine sahip ve stokastik, spesifik olmayan arka plan çapraz etkileşim-linking özellikle konsantre örneklerinde, yüksek olabilir. Bu zor-yorumlama sonuçlara yol açabilir. Burada, bir hibrid BN-PAGE / SDS-PAGE yöntemiyle kullanımını gösteren, ayrı ve kompleks karışımlar protein derlemeleri tespit etmek için, multimeri-poliakrilamid jel elektroforezi (multimer-PAGE) olarak adlandırılır. Başlangıçta, hücre lizatı, BN-PAGE ile poliakrilamid jel içinde süspansiyon haline getirilir. lizat içeren Jel daha sonra çapraz bağlama reaktifi DSP ile reaksiyona sokulur. Sözde hareketsiz ve biraz jeli üzerinde ayrıldı, proteinler arka çapraz bağlayıcı tepkime azalır, yani daha az spesifik olmayan bir tepki muhtemeldir. Çapraz bağlanma sonrası, jel, bantlar kesilir ve SDS-PAGE ile ayrılmıştır. Elde edilen jel daha sonra, tipik olarak poliakrilamid jel elektroforezi ile ilişkili herhangi bir yolla analiz edilebilir. Bu yöntem, ilave saflaştırma veya çekme Dow gerek kalmadan, modifiye edilmemiş doku lizatındaki doğal protein komplekslerinin ayrıştırılması ve algılanması amacıyla sağlarn.

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			<td height="21" style="height:21px;width:336px;">Chemicals</td>
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			<td height="21" style="height:21px;width:336px;">&#949;-Aminocaproic acid</td>
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			<td height="21" style="height:21px;width:336px;">Acrylamide</td>
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		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:336px;">Acrylamide/bisacrilamide 37.5:1 (40%T stock solution)</td>
			<td style="width:195px;">BioRad</td>
			<td style="width:119px;">161-0148</td>
			<td>Toxic.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Ammonium persulfate</td>
			<td style="width:195px;">Sigma</td>
			<td style="width:119px;">A3678</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Anti rabbit IgG-HRP from goat</td>
			<td style="width:195px;">Santa Cruz Biotechnology</td>
			<td style="width:119px;">sc-2004</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Bicinchoninic acid assay kit</td>
			<td style="width:195px;">Thermofisher</td>
			<td style="width:119px;">23225</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Bis-tris</td>
			<td style="width:195px;">Sigma</td>
			<td style="width:119px;">B9754</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Bovine serum albumin</td>
			<td style="width:195px;">Sigma</td>
			<td style="width:119px;">A9647</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Butanol</td>
			<td style="width:195px;">Fisher Scientific</td>
			<td style="width:119px;">A399-1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Chemiluminescence substrate kit</td>
			<td style="width:195px;">ThermoFisher</td>
			<td style="width:119px;">24078</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Coomassie blue G-250</td>
			<td style="width:195px;">Sigma-Aldrich</td>
			<td style="width:119px;">B0770</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Digitonin</td>
			<td style="width:195px;">Sigma</td>
			<td style="width:119px;">D141</td>
			<td>Toxic.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Dimethyl sulfoxide</td>
			<td style="width:195px;">Fisher Scientific</td>
			<td style="width:119px;">D128-1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Dithiobis(succinimidylpropionate)</td>
			<td style="width:195px;">Thermo Scientific</td>
			<td style="width:119px;">22585</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Dry nonfat milk</td>
			<td style="width:195px;">LabScientific</td>
			<td style="width:119px;">M0841</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Glycerol</td>
			<td style="width:195px;">Sigma</td>
			<td style="width:119px;">G9012</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Glycine</td>
			<td style="width:195px;">Fisher Scientific</td>
			<td style="width:119px;">BP381-5</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Halt Protease Inhibitor Cocktail</td>
			<td style="width:195px;">Thermofisher</td>
			<td>78430</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Hydrochloric acid</td>
			<td style="width:195px;">Fisher Scientific</td>
			<td style="width:119px;">A144SI-212</td>
			<td>For titration. Caustic.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Methanol</td>
			<td style="width:195px;">Fisher Scientific</td>
			<td style="width:119px;">A412-4</td>
			<td>For PVDF membrane activation. Toxic.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Monoclonal anti &#945;-synuclein IgG from rabbit</td>
			<td style="width:195px;">Santa Cruz Biotechnology</td>
			<td style="width:119px;">sc-7011-R</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">N,N,N&#39;,N&#39;-tetramethylethylenediamine</td>
			<td style="width:195px;">Sigma</td>
			<td style="width:119px;">T9281</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">N,N&#39;-methylenebisacrylamide</td>
			<td style="width:195px;">Acros Organics</td>
			<td style="width:119px;">16479</td>
			<td>Toxic.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">NP40</td>
			<td style="width:195px;">Boston Bioproducts</td>
			<td style="width:119px;">P-872</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Polysorbate 20 (tween-20)</td>
			<td style="width:195px;">Fisher Scientific</td>
			<td style="width:119px;">BP337-500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Polyvinylidene fluoride transfer membranes</td>
			<td style="width:195px;">Thermo Scientific</td>
			<td style="width:119px;">88518</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Ponceau S</td>
			<td style="width:195px;">Sigma</td>
			<td style="width:119px;">P3504</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Potassium chloride</td>
			<td style="width:195px;">Fisher Scientific</td>
			<td style="width:119px;">P217-3</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Potassium phosphate monobasic</td>
			<td style="width:195px;">Sigma</td>
			<td style="width:119px;">P9791</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Protease inhibitor cocktail</td>
			<td style="width:195px;">Thermo Scientific</td>
			<td style="width:119px;">88265</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">SDS solution (10% w/v)</td>
			<td style="width:195px;">BioRad</td>
			<td style="width:119px;">161-0416</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Sodium chloride</td>
			<td style="width:195px;">Fisher Scientific</td>
			<td style="width:119px;">BP358-212</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Sodium dodecyl sulfate</td>
			<td style="width:195px;">Sigma</td>
			<td style="width:119px;">L37771</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Sodium phosphate monobasic</td>
			<td style="width:195px;">Fisher Scientific</td>
			<td style="width:119px;">BP329-1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Tricine</td>
			<td style="width:195px;">Sigma</td>
			<td style="width:119px;">T0377</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Tris base</td>
			<td style="width:195px;">Fisher Scientific</td>
			<td style="width:119px;">BP152-500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Tris-HCl (0.5 M buffer, pH 6.8)</td>
			<td style="width:195px;">BioRad</td>
			<td style="width:119px;">161-0799</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Tris-HCl (1.5 M buffer, pH 8.8)</td>
			<td style="width:195px;">BioRad</td>
			<td style="width:119px;">161-0798</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Name</td>
			<td style="width:195px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Instruments</td>
			<td style="width:195px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">GE Imagequant LAS 4000</td>
			<td style="width:195px;">GE Healthcare</td>
			<td style="width:119px;">28-9558-10</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">ImageJ software</td>
			<td style="width:195px;">NIH</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Synergy H1 microplate reader</td>
			<td style="width:195px;">BioTek</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Gel Former + Stand</td>
			<td style="width:195px;">Biorad</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Microfuge 22R centrifuge</td>
			<td style="width:195px;">Beckman Coulter</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">2 mL dounce homogenizer</td>
			<td style="width:195px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Vortex mixer</td>
			<td style="width:195px;">Fisher Scientific</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:336px;">Ultrasonic tissue homogenizer</td>
			<td style="width:195px;">Fisher Scientific</td>
			<td style="width:119px;">FB120220</td>
			<td></td>
		</tr>
	</tbody>
</table>

multimer-page: a method for capturing and resolving protein complexes in biological samples

arındırıcı ve tek proteinler ve peptidler çalışmak için pek iyi gelişmiş yöntemler vardır. Bununla birlikte, en çok hücresel işlev, sıklıkla, kovalent olmayan ve kolay bir saflaştırma teknikleri ile bozulmuş olan bir bağlanma araştırılması için zor olan etkileşimli protein komplekslerinin ağlar tarafından gerçekleştirilmektedir. Bu çalışma, stabilize edici ve iki boyutlu poliakrilamit jel elektroforez ile modifiye edilmemiş dokusundan doğal protein kompleksleri ayırmak için bir yöntem tarif eder. Doku lisatı, protein jel içine kısa bir mesafede yer değiştirmektedir kadar sonra bir elektrik akımı uygulandığında, bir denatüre edici olmayan mavi doğal poliakrilamid jel üzerine yüklenir. Taşınan protein ihtiva eden jel şeridi daha sonra kesilmiş ve kovalent protein kompleksleri stabilize amin reaktif çapraz bağlama reaktifi ditiobis (sukinimidil propionat) ile inkübe edilir. çapraz bağlı kompleksler ihtiva eden jel şeridi daha sonra bir sodyum dodesil sülfat poliakrilamid jel içine dökülür, ve t,O kompleksleri tamamen ayrılır. yöntem ucuz ve öğrenmesi kolay, yani teknikleri ve en moleküler biyologlar için tanıdık malzemelere dayanır. yeterince aşırı büyük kompleksleri ayırmak için yeteneği sınırlıdır ve evrensel başarılı olmamıştır da, yöntem iyi çalışılmış komplekslerinin çeşitli yakalamak başardı ve ilgi birçok sistemde muhtemelen geçerlidir.

Bu gösteri deneyinde, multimeir-PAGE bütün sıçan beyni lizatının gerçekleştirildi. Elde edilen ayrılan proteinler poliviniliden diflouride (PVDF) membran üzerinde lekelenir ve sonra kompleksler oluşturmak üzere bilinen proteinlere karşı antikorlar ile problanmıştır. Şekil 1, iki ile protokolünün bir doğrulama gösterir. İlk olarak, çapraz bağlanmış proteinler, çapraz bağlama reaktifi ile oluşturulmaktadır gözlenen daha yüksek molekül ağ...

Watch this Scientific Journal Video about Multimer-PAGE: A Method for Capturing and Resolving Protein Complexes in Biological Samples at JoVE.com

Multimer-PAGE: A Method for Capturing and Resolving Protein Complexes in Biological Samples

stabilize edici ve yeni bir iki boyutlu poliakrilamit jel elektroforez bağlanmış bir amin-reaktif protein çapraz bağlayıcı kullanılarak modifiye edilmemiş doku lizattan doğal protein kompleksleri ayırmak için bir yöntem olup (PAGE) sistemi sunulmuştur.

Multimer-PAGE: Biyolojik örnekler olarak yakalamak için bir yöntem ve özümleme protein kompleksleri

There are many well-developed methods for purifying and studying single proteins and peptides. However, most cellular functions are carried out by ...

multimer-page-method-for-capturing-resolving-protein-complexes

Research

JoVE Journal

Biochemistry

11.3K Görüntüleme.  Michigan State University.  stabilize edici ve yeni bir iki boyutlu poliakrilamit jel elektroforez bağlanmış bir amin-reaktif protein çapraz bağlayıcı kullanılarak modifiye edilmemiş doku lizattan doğal protein kompleksleri ayırmak için bir yöntem olup (PAGE) sistemi sunulmuştur. 

Video: Multimer-PAGE: A Method for Capturing and Resolving Protein Complexes in Biological Samples

Sheathless Capillary Electrophoresis&#8211;Mass Spectrometry for Metabolic Profiling of Biological Samples

In metabolomics, a wide range of analytical techniques is used for the global profiling of (endogenous) metabolites in complex samples. In this paper, a protocol is presented for the analysis of anionic and cationic metabolites in biological samples by capillary electrophoresis&#8211;mass spectrometry (CE-MS). CE is well-suited for the analysis of highly polar and charged metabolites as compounds are separated on the basis of their charge-to-size ratio. A recently developed sheathless interfacing design, i.e., a porous tip interface, is used for coupling CE to electrospray ionization (ESI) MS. This interfacing approach allows the effective use of the intrinsically low-flow property of CE in combination with MS, resulting in nanomolar detection limits for a broad range of polar metabolite classes. The protocol presented here is based on employing a bare fused-silica capillary with a porous tip emitter at low-pH separation conditions for the analysis of a broad array of metabolite classes in biological samples. It is demonstrated that the same sheathless CE-MS method can be used for the profiling of cationic metabolites, including amino acids, nucleosides and small peptides, or anionic metabolites, including sugar phosphates, nucleotides and organic acids, by only switching the MS detection and separation voltage polarity. Highly information-rich metabolic profiles in various biological samples, such as urine, cerebrospinal fluid and extracts of the glioblastoma cell line, can be obtained by this protocol in less than 1 hr of CE-MS analysis.

A protocol for metabolic profiling of biological samples by capillary electrophoresis&#8211;mass spectrometry using a sheathless porous tip interface design is presented.

Biyolojik Numune metabolik profil için Sheathless Kapiler Elektroforez-Kütle Spektrometre

In metabolomics, a wide range of analytical techniques is used for the global profiling of (endogenous) metabolites in complex samples. In this paper, a ...

Biyokimya

Method for Identifying Small Molecule Inhibitors of the Protein-protein Interaction Between HCN1 and TRIP8b

Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are expressed ubiquitously throughout the brain, where they function to regulate the excitability of neurons. The subcellular distribution of these channels in pyramidal neurons of hippocampal area CA1 is regulated by tetratricopeptide repeat-containing Rab8b interacting protein (TRIP8b), an auxiliary subunit. Genetic knockout of HCN pore forming subunits or TRIP8b, both lead to an increase in antidepressant-like behavior, suggesting that limiting the function of HCN channels may be useful as a treatment for Major Depressive Disorder (MDD). Despite significant therapeutic interest, HCN channels are also expressed in the heart, where they regulate rhythmicity. To circumvent off-target issues associated with blocking cardiac HCN channels, our lab has recently proposed targeting the protein-protein interaction between HCN and TRIP8b in order to specifically disrupt HCN channel function in the brain. TRIP8b binds to HCN pore forming subunits at two distinct interaction sites, although here the focus is on the interaction between the tetratricopeptide repeat (TPR) domains of TRIP8b and the C terminal tail of HCN1. In this protocol, an expanded description of a method for purifying TRIP8b and executing a high throughput screen to identify small molecule inhibitors of the interaction between HCN and TRIP8b, is described. The method for high throughput screening utilizes a Fluorescence Polarization (FP) -based assay to monitor the binding of a large TRIP8b fragment to a fluorophore-tagged eleven amino acid peptide corresponding to the HCN1 C terminal tail. This method allows &#39;hit&#39; compounds to be identified based on the change in the polarization of emitted light. Validation assays are then performed to ensure that &#39;hit&#39; compounds are not artifactual.

The interaction between HCN channels and their auxiliary subunit has been identified as a therapeutic target in Major Depressive Disorder. Here, a fluorescence polarization-based method for identifying small molecule inhibitors of this protein-protein interaction, is presented.

Yöntem HCN1 ve TRIP8b arasında protein-protein etkileşimi küçük molekül önleyicilerinin tespit edilmesi için

Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are expressed ubiquitously throughout the brain, where they function to regulate the ...

Time-resolved ElectroSpray Ionization Hydrogen-deuterium Exchange Mass Spectrometry for Studying Protein Structure and Dynamics

Intrinsically disordered proteins (IDPs) have long been a challenge to structural biologists due to their lack of stable secondary structure elements. Hydrogen-Deuterium Exchange (HDX) measured at rapid time scales is uniquely suited to detect structures and hydrogen bonding networks that are briefly populated, allowing for the characterization of transient conformers in native ensembles. Coupling of HDX to mass spectrometry offers several key advantages, including high sensitivity, low sample consumption and no restriction on protein size. This technique has advanced greatly in the last several decades, including the ability to monitor HDX labeling times on the millisecond time scale. In addition, by incorporating the HDX workflow onto a microfluidic platform housing an acidic protease microreactor, we are able to localize dynamic properties at the peptide level. In this study, Time-Resolved ElectroSpray Ionization Mass Spectrometry (TRESI-MS) coupled to HDX was used to provide a detailed picture of residual structure in the tau protein, as well as the conformational shifts induced upon hyperphosphorylation.

Conformational flexibility plays a critical role in protein function. Herein, we describe the use of time-resolved electrospray ionization mass spectrometry coupled to hydrogen-deuterium exchange for probing the rapid structural changes that drive function in ordered and disordered proteins.

Zaman çözülmesi elektro sprey iyonizasyon Hidrojen-döteryum Değişim Kütle Spektrometre Protein Yapısı ve Dinamikleri incelenmesi için

Intrinsically disordered proteins (IDPs) have long been a challenge to structural biologists due to their lack of stable secondary structure elements. ...

Resolving Affinity Purified Protein Complexes by Blue Native PAGE and Protein Correlation Profiling

Most proteins act in association with others; hence, it is crucial to characterize these functional units in order to fully understand biological processes. Affinity purification coupled to mass spectrometry (AP-MS) has become the method of choice for identifying protein-protein interactions. However, conventional AP-MS studies provide information on protein interactions, but the organizational information is lost. To address this issue, we developed a strategy to unravel the distinct functional assemblies a protein might be involved in, by resolving affinity-purified protein complexes prior to their characterization by mass spectrometry. Protein complexes isolated through affinity purification of a bait protein using an epitope tag and competitive elution are separated through blue native electrophoresis. Comparison of protein migration profiles through correlation profiling using quantitative mass spectrometry allows assignment of interacting proteins to distinct molecular entities. This method is able to resolve protein complexes of close molecular weights that might not be resolved by traditional chromatographic techniques such as gel filtration. With little more work than conventional AP-geLC-MS/MS, we demonstrate this strategy may in many cases be adequate for obtaining protein complex topological information concomitantly to identifying protein interactions.

Here we present protocols for affinity purification of protein complexes and their separation by blue native PAGE, followed by protein correlation profiling using label free quantitative mass spectrometry. This method is useful to resolve interactomes into distinct protein complexes.

Mavi Yerli PAGE ve Protein İlişkisi Profil Yöntemi ile Affinity Saf protein Kompleksler çözümleniyor

Most proteins act in association with others; hence, it is crucial to characterize these functional units in order to fully understand biological ...

Detection and Visualization of DNA Damage-induced Protein Complexes in Suspension Cell Cultures Using the Proximity Ligation Assay

The DNA damage response orchestrates the repair of DNA lesions that occur spontaneously, are caused by genotoxic stress, or appear in the context of programmed DNA breaks in lymphocytes. The Ataxia-Telangiectasia Mutated kinase (ATM), ATM- and Rad3-Related kinase (ATR) and the catalytic subunit of DNA-dependent Protein Kinase (DNA-PKcs) are among the first that are activated upon induction of DNA damage, and are central regulators of a network that controls DNA repair, apoptosis and cell survival. As part of a tumor-suppressive pathway, ATM and ATR activate p53 through phosphorylation, thereby regulating the transcriptional activity of p53. DNA damage also results in the formation of so-called ionizing radiation-induced foci (IRIF) that represent complexes of DNA damage sensor and repair proteins that accumulate at the sites of DNA damage, which are visualized by fluorescence microscopy. Co-localization of proteins in IRIFs, however, does not necessarily imply direct protein-protein interactions, as the resolution of fluorescence microscopy is limited. 
In situ Proximity Ligation Assay (PLA) is a novel technique that allows the direct visualization of protein-protein interactions in cells and tissues with unprecedented specificity and sensitivity. This technique is based on the spatial proximity of specific antibodies binding to the proteins of interest. When the interrogated proteins are within ~40 nm an amplification reaction is triggered by oligonucleotides that are conjugated to the antibodies, and the amplification product is visualized by fluorescent labeling, yielding a signal that corresponds to the subcellular location of the interacting proteins. Using the established functional interaction between ATM and p53 as an example, it is demonstrated here how PLA can be used in suspension cell cultures to study the direct interactions between proteins that are integral parts of the DNA damage response.

Here, it is demonstrated how the in situ Proximity Ligation Assay (PLA) can be used to detect and visualize the direct protein-protein interactions between ATM and p53 in suspension cell cultures exposed to genotoxic stress.

Proximity Ligation Testi ile Süspansiyon Hücre Kültürlerinde DNA Hasarına Bağlı Protein Komplekslerinin Saptanması ve Görselleştirilmesi

The DNA damage response orchestrates the repair of DNA lesions that occur spontaneously, are caused by genotoxic stress, or appear in the context of ...

Horizontal Gel Electrophoresis for Enhanced Detection of Protein-RNA Complexes

Native polyacrylamide gel electrophoresis is a fundamental tool of molecular biology that has been used extensively for the biochemical analysis of RNA-protein interactions. These interactions have been traditionally analyzed with polyacrylamide gels generated between two glass plates and samples electrophoresed vertically. However, polyacrylamide gels cast in trays and electrophoresed horizontally offers several advantages. For example, horizontal gels used to analyze complexes between fluorescent RNA substrates and specific proteins can be imaged multiple times as electrophoresis progresses. This provides the unique opportunity to monitor RNA-protein complexes at several points during the experiment. In addition, horizontal gel electrophoresis makes it possible to analyze many samples in parallel. This can greatly facilitate time course experiments as well as analyzing multiple reactions simultaneously to compare different components and conditions. Here we provide a detailed protocol for generating and using horizontal native gel electrophoresis for analyzing RNA-Protein interactions.

Native polyacrylamide gel electrophoresis is a fundamental tool for analyzing RNA-protein interactions. Traditionally most experiments have used vertical gels. However, horizontal gels provide several advantages, such as the opportunity to monitor complexes during electrophoresis. We provide a detailed protocol for generating and using horizontal native gel electrophoresis.

Protein-RNA Komplekslerinin Geliştirilmiş Algılaması için Yatay Jel Elektroforezi

Native polyacrylamide gel electrophoresis is a fundamental tool of molecular biology that has been used extensively for the biochemical analysis of ...

2 in 1: One-step Affinity Purification for the Parallel Analysis of Protein-Protein and Protein-Metabolite Complexes

Cellular processes are regulated by interactions between biological molecules such as proteins, metabolites, and nucleic acids. While the investigation of protein-protein interactions (PPI) is no novelty, experimental approaches aiming to characterize endogenous protein-metabolite interactions (PMI) constitute a rather recent development. Herein, we present a protocol that allows simultaneous characterization of the PPI and PMI of a protein of choice, referred to as bait. Our protocol was optimized for Arabidopsis cell cultures and combines affinity purification (AP) with mass spectrometry (MS)-based protein and metabolite detection. In short, transgenic Arabidopsis lines, expressing bait protein fused to an affinity tag, are first lysed to obtain a native cellular extract. Anti-tag antibodies are used to pull down protein and metabolite partners of the bait protein. The affinity-purified complexes are extracted using a one-step methyl tert-butyl ether (MTBE)/methanol/water method. Whilst metabolites separate into either the polar or the hydrophobic phase, proteins can be found in the pellet. Both metabolites and proteins are then analyzed by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS or UPLC-MS/MS). Empty-vector (EV) control lines are used to exclude false positives. The major advantage of our protocol is that it enables identification of protein and metabolite partners of a target protein in parallel in near-physiological conditions (cellular lysate). The presented method is straightforward, fast, and can be easily adapted to biological systems other than plant cell cultures.

Protein-protein and protein-metabolite interactions are crucial for all cellular functions. Herein, we describe a protocol that allows parallel analysis of these interactions with a protein of choice. Our protocol was optimized for plant cell cultures and combines affinity purification with mass spectrometry-based protein and metabolite detection.

2 in 1: tek adımlı benzeşme arıtma paralel analizi için Protein-Protein ve Protein-metaboliti kompleksleri

Cellular processes are regulated by interactions between biological molecules such as proteins, metabolites, and nucleic acids. While the investigation of ...

Use of Electron Paramagnetic Resonance in Biological Samples at Ambient Temperature and 77 K

The accurate and specific detection of reactive oxygen species (ROS) in different cellular and tissue compartments is essential to the study of redox-regulated signaling in biological settings. Electron paramagnetic resonance spectroscopy (EPR) is the only direct method to assess free radicals unambiguously. Its advantage is that it detects physiologic levels of specific species with a high specificity, but it does require specialized technology, careful sample preparation, and appropriate controls to ensure accurate interpretation of the data. Cyclic hydroxylamine spin probes react selectively with superoxide or other radicals to generate a nitroxide signal that can be quantified by EPR spectroscopy. Cell-permeable spin probes and spin probes designed to accumulate rapidly in the mitochondria allow for the determination of superoxide concentration in different cellular compartments.
In cultured cells, the use of cell permeable 1-hydroxy-3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine (CMH) along with and without cell-impermeable superoxide dismutase (SOD) pretreatment, or use of cell-permeable PEG-SOD,&#160;allows for the differentiation of extracellular from cytosolic superoxide. The mitochondrial 1-hydroxy-4-[2-triphenylphosphonio)-acetamido]-2,2,6,6-tetramethyl-piperidine,1-hydroxy-2,2,6,6-tetramethyl-4-[2-(triphenylphosphonio)acetamido] piperidinium dichloride (mito-TEMPO-H) allows for measurement of mitochondrial ROS (predominantly superoxide).
Spin probes and EPR spectroscopy can also be applied to in vivo models. Superoxide can be detected in extracellular fluids such as blood and alveolar fluid, as well as tissues such as lung tissue. Several methods are presented to process and store tissue for EPR measurements and deliver intravenous 1-hydroxy-3-carboxy-2,2,5,5-tetramethylpyrrolidine (CPH) spin probe in vivo. While measurements can be performed at room temperature, samples obtained from in vitro and in vivo models can also be stored at -80 &#176;C and analyzed by EPR at 77 K. The samples can be stored in specialized tubing stable at -80 &#176;C and run at 77 K to enable a practical, efficient, and reproducible method that facilitates storing and transferring samples.

Electron paramagnetic resonance (EPR) spectroscopy is an unambiguous method to measure free radicals. The use of selective spin probes allows for detection of free radicals in different cellular compartments. We present a practical, efficient method to collect biological samples that facilitate treating, storing, and transferring samples for EPR measurements.

Elektron Paramagnetic rezonans ortam sıcaklığı ve 77 K biyolojik örneklerde kullanımı

The accurate and specific detection of reactive oxygen species (ROS) in different cellular and tissue compartments is essential to the study of ...

Single-step Purification of Macromolecular Complexes Using RNA Attached to Biotin and a Photo-cleavable Linker

For many years, the exceptionally strong and rapidly formed interaction between biotin and streptavidin has been successfully utilized for partial purification of biologically important RNA/protein complexes. However, this strategy suffers from one major disadvantage that limits its broader utilization: the biotin/streptavidin interaction can be broken only under denaturing conditions that also disrupt the integrity of the eluted complexes, hence precluding their subsequent functional analysis and/or further purification by other methods. In addition, the eluted samples are frequently contaminated with the background proteins that nonspecifically associate with streptavidin beads, complicating the analysis of the purified complexes by silver staining and mass spectrometry. To overcome these limitations, we developed a variant of the biotin/streptavidin strategy in which biotin is attached to an RNA substrate via a photo-cleavable linker and the complexes immobilized on streptavidin beads are selectively eluted to solution in a native form by long wave UV, leaving the background proteins on the beads. Shorter RNA binding substrates can be synthesized chemically with biotin and the photo-cleavable linker covalently attached to the 5&#39; end of the RNA, whereas longer RNA substrates can be provided with the two groups by a complementary oligonucleotide. These two variants of the UV-elution method were tested for purification of the U7 snRNP-dependent processing complexes that cleave histone pre-mRNAs at the 3&#39; end and they both proved to compare favorably to other previously developed purification methods. The UV-eluted samples contained readily detectable amounts of the U7 snRNP that was free of major protein contaminants and suitable for direct analysis by mass spectrometry and functional assays. The described method can be readily adapted for purification of other RNA binding complexes and used in conjunction with single- and double-stranded DNA binding sites to purify DNA-specific proteins and macromolecular complexes.

RNA/protein complexes purified using botin-streptavidin strategy are eluted to solution under denaturing conditions in a form unsuitable for further purification and functional analysis. Here, we describe a modification of this strategy that utilizes a photo-cleavable linker in RNA and a gentle UV-elution step, yielding native and fully functional RNA/protein complexes.

Tek adım arıtma RNA bağlı Biotin ve fotoğraf yarilabilir bir bağlayıcı kullanarak makromoleküllerin kompleksleri

For many years, the exceptionally strong and rapidly formed interaction between biotin and streptavidin has been successfully utilized for partial ...

Analysis of Protein Folding, Transport, and Degradation in Living Cells by Radioactive Pulse Chase

Radioactive pulse-chase labeling is a powerful tool for studying the conformational maturation, the transport to their functional cellular location, and the degradation of target proteins in live cells. By using short (pulse) radiolabeling times (&lt;30 min) and tightly controlled chase times, it is possible to label only a small fraction of the total protein pool and follow its folding. When combined with nonreducing/reducing SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoprecipitation with (conformation-specific) antibodies, folding processes can be examined in great detail. This system has been used to analyze the folding of proteins with a huge variation in properties such as soluble proteins, single and multi-pass transmembrane proteins, heavily N- and O-glycosylated proteins, and proteins with and without extensive disulfide bonding. Pulse-chase methods are the basis of kinetic studies into a range of additional features, including co- and posttranslational modifications, oligomerization, and polymerization, essentially allowing the analysis of a protein from birth to death. Pulse-chase studies on protein folding are complementary with other biochemical and biophysical methods for studying proteins in vitro by providing increased temporal resolution and physiological information. The methods as described within this paper are adapted easily to study the folding of almost any protein that can be expressed in mammalian or insect-cell systems.

Here we describe a protocol for a general pulse-chase method that allows the kinetic analysis of folding, transport, and degradation of proteins to be followed in live cells.

Protein katlanması, taşıma ve canlı hücreler radyoaktif darbe Chase tarafından bozulması Analizi

Radioactive pulse-chase labeling is a powerful tool for studying the conformational maturation, the transport to their functional cellular location, and ...