Bu çalışma, Johns Hopkins ALS Araştırma Packard Merkezi (ADG), NIH Müdürü Yenilikçisi Ödülü 1DP2OD004417-01 (ADG), NIH R01 NS065317 (ADG), Rita Allen Vakfı Scholar Ödülü bir hibe ile desteklenmiştir. ADG Pew Charitable Ortaklıkları tarafından desteklenen Biyomedikal Bilimler Pew Scholar.

1. Maya dönüşüm için hazırlıklar Bu protokol on 96-kuyucuğu için tasarlanmıştır ancak bu doğrultuda yukarı veya aşağı ölçeklendirilebilir. Biz bu protokolü, dönüşüm yuvarlak başına yirmiden fazla 96 kuyucuğu için iyi olmadığını bulduk. Tüm dönüşüm prosedürü (adım I.3) yaklaşık sekiz saat sürer. <ol><li> Kısım yuvarlak bir alt her kuyuya Biorobot RapidPlate sıvı işleyici 96-plaka Maya FLEXGene ORF kütüphane plazmid DNA (100 ng / ul) 5-10μL. Place kuru geceleme temiz tezgah davlumbaz 96-kuyucuğu ortaya çıkardı. Biz CEN ve 2μ maya plazmid ile benzer dönüşüm verimliliği bulduk. </li><li> Maya pepton dekstroz (YPD) medya (10g / L maya özü, 20g / L pepton, 20g / L glukoz) ve 200 ml 500ml şaşkın Erlenmeyer şişesinin sorgu suşu ile inoküle edin. Sallayarak (200 rpm) ile 30 ° C&#39;de bir gece inkübe edin. Gerekirse, seçici medya bu starter kültürler için de kullanılabilir. </li><li> Ertesi sabah, sorgu gerginlik OD 600 = 0.1 YPD, 2L sulandırmak. 30 ° C (200 rpm) kültürü OD 600 = 0.8-1.0 ulaşıncaya kadar 4-6 saat çalkalanır. Optimum büyüme için, iki ayrı 2.8 L şaşkın şişeler 1L kültürler büyüyorlar. Gerekirse, seçici medya da YPD yerine kullanılan olabilir. </li></ol> 2. Maya dönüşüm <ol><li> Hasat hücreler santrifüj yoluyla. 5 dakika masaüstü santrifüj (Eppendorf 5810R) 3000rpm (~ 1800 xg) maya kültürü ve spin ile dört tek 225mL konik tüpler doldurun. Süpernatant dökün ve tüm hücreleri hasat kadar tekrarlayın. </li><li> Otoklavlanmış distile H 2 O. 200ml hücrelerin yıkayın Sallayarak veya vorteks yeniden süspanse hücre pelletini. 225mL konik bir tüp içinde hücreleri birleştirin. 5 dakika 3000rpm dönerler. Süpernatantı. </li><li> 0.1MLiOAc/1XTE çözüm (0.1M LiOAc, 10mM Tris, 1mm EDTA, otoklavlanmış distile su, pH 8) hazırlayın. 100 ml 0.1MLiOAc/1XTE hücrelerin yıkayın. 5 dakika 3000rpm dönerler. Süpernatantı. </li><li> 70mL 0.1M LiOAc/1xTE yeniden süspanse hücre pelletini. Shake ve / veya vorteks pelet tamamen yeniden süspanse sağlamak için. </li><li> 30 ° C&#39;de 30 dakika (200 rpm) sallayarak inkübe edin. </li><li> 0.1M için β-mercaptoethanol ekleyin. 30 ° C&#39;de 30 dakika (200 rpm) sallayarak inkübe edin. Not: beta-mercaptoethanol duyarlı maya suşu kullanılarak, bu adım atlanabilir. Biz bu adımı başarılı bir dönüşüm için zorunlu olduğunu bulduk, ancak dönüşüm verimliliği artırmak. </li><li> Sonicated somon sperm DNA (10mg/ml) 2mL 15 dakika boyunca kaynatın ve ardından buz üzerinde soğutun. </li><li> 2mL haşlanmış somon sperm DNA hücre karışımı ekleyin. Dikkat: hücre karışımı somon sperm DNA eklenmesi halinde bir çökelti. Pipetman ve 200 ul ucu kullanarak, dikkatli bir şekilde bu mansap pipetleme engel olabilir çünkü formları herhangi bir çökelti kaldırın. </li><li> 96-plaka BioRobot Rapidplate kullanarak her bir kuyunun hücre karışımı kısım 50μL (aynı zamanda çok kanallı pipet kullanabilirsiniz). Karışmaz. </li><li> Sallayarak 30 dakika oda sıcaklığında inkübe edin. </li><li> 200ml 40% PEG-3350/10% DMSO/0.1M LiOAc (160mL% 50 PEG-3350, 20ml DMSO, 20ml 1M LiOAc) hazırlayın. Kullanımdan hemen önce çözüm hazırlayın. </li><li> Her iyi PEG / LioAc / DMSO çözüm 125μL ekleyin. RapidPlate ile sekiz kez aspire ve hücre süspansiyonu dağıtım karıştırın. </li><li> Sallayarak 30 dakika oda sıcaklığında inkübe edin. </li><li> Isı şok hücreleri 42 ° C 15 dakika boyunca kuru bir inkübatör. Plakalar koymayın. Not: Bu ısı şok adım başarılı bir dönüşüm için gerekli olduğunu bulduk. Bazı maya suşları (örneğin, ısıya duyarlı mutantlar), ısı şok zararlı. Daha önce bir dakika ısı şok süresini azalttı ve bu protokolü kullanarak ypt1 ısıya duyarlı mutasyon barındıran bir maya suşu başarıyla dönüştürmek mümkün olmuştur. </li><li> 96-kuyucuğu karşılamak için santrifüj adaptörleri kullanarak, 5 dakika için 2500rpm (~ 1100 xg) plakaları Spin. Atık kovası üzerinde tersini plakaları ile PEG çözüm çıkarın. Kalan sıvı kaldırmak için kağıt havlu üzerine ters plaka Blot (hücreleri kuyu altında kalacaktır). </li><li> RapidPlate her iyi minimal medya 200μL ekleyerek (örneğin SD /-Ura) hücreleri durulayın. </li><li> 2500rpm az 5 dakika boyunca plakalar Spin ve tersini üzerinde atık kovası ve kağıt havlu üzerinde blot süpernatant kaldırmak. </li><li> RapidPlate ile her kuyuya 200μL minimal medya (örneğin SD /-Ura) ekleyin. </li><li> Titreme olmadan 2 gün boyunca 30 ° C&#39;de inkübe edin. 2 gün sonra, hücre başarıyla iyi dönüştürülmüş her altındaki küçük koloniler oluşturmak için başlamalıdır. </li></ol> 3. Tahlil Spotting <ol><li> Her kuyuya raffinose tabanlı minimal medya (örneğin SRaf /-Ura) 200μL Uygulamayeni bir düz-alt 96-plaka. </li><li> Rapidplate ile sekiz kez aspire ve hücre süspansiyonu dağıtım dönüşüm plaka her iyi karıştırın. </li><li> Dönüşüm plaka hücre karışımı 5μL ile SRaf plakalarını aşılamak. </li><li> Bir gün için 30 ° C&#39;de inkübe edin. Küçük kolonileri bir gün sonra, her bir kuyunun dibinde mevcut olmalıdır. </li><li> SD / Ura ve kaputu SGal /-Ura plakaları Spot koloniler. 96-cıvata çoğaltıcı (Frogger) alev tarafından sterilize edin. Frogger ile seçici besiyerleri plakaları lekelenme önce koloniler karıştırın. Lekelenme sonra, tabak, 5-10 dakika kaputu kurumasını bekleyin. </li><li> 2-3 gün boyunca 30 ° C&#39;de inkübe edin. </li></ol> Dijital kamera ile fotoğraf plakaları ve görsel SGal /-Ura plakaları sorgu gerginlik toksisite (hızlı büyüme / daha yoğun koloniler) (daha yavaş büyüme / daha az yoğun koloniler) ya da bastırılmış gelişmiş olduğu koloniler bulmak için kolonilerin büyüme karşılaştırmak. 4. Temsilcisi sonuçları: <img src="/files/ftp_upload/2836/2836fig1.jpg" alt="Şekil 1"/> Şekil 1. Maya plazmid aşırı ekspresyonu TDP-43 toksisite bastırıcılarının ve arttırıcılar tanımlamak için ekran. TDP-43 Amyotrofik lateral skleroz (Lou Gehrig hastalığı) patogenezinde sorumlu olan bir insan proteini. TDP-43 Sitoplazmik agrega ALS hastası 17 beyin ve omurilik nöronlarının birikir. Agregasyonu ve sitotoksisite 18 maya hücreleri sonuçları ifade TDP-43. Biz TDP-43 toksisite 19,20 mekanizmaları tanımlamak için bu model sistem kullandık. Gösterilen bizim maya TDP-43 toksisite değiştirici ekran plaka repesentative örnekler. Bu plakalar FLEXGene ORF ifade kütüphane plazmid ile entegre bir galaktoz-indüklenebilir TDP-43 plazmid ve aynı zamanda dönüştürülmüş koloniler gösterilecek. Soldaki plaka TDP-43 veya FLEXGene plazmid ifade bastıran glikoz içerir. Sağdaki plaka TDP-43 ekspresyonu ve FLEXGene plazmid Orfs neden olur galaktoz içerir. Yeşil ok ucu TDP-43 toksisite bastırır bir plazmid ile dönüştürülmüş bir koloni gösterir. Kırmızı ok ucu TDP-43 toksisitesini arttırır bir plazmid ile dönüştürülmüş bir koloni gösterir.

<ol>
	<li>Nurse, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Nobel+Prize+and+beyond:+an+interview+with+Sir+Paul+Nurse.+Interview+by+Susan+R.+Owens.">The Nobel Prize and beyond: an interview with Sir Paul Nurse. Interview by Susan R. Owens.</a> EMBO Rep. 3, 204-206 (2002).</li><li>Hartwell, L. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nobel+Lecture.+Yeast+and+cancer.">Nobel Lecture. Yeast and cancer.</a> Biosci Rep. 22, 373-394 (2002).</li><li>Stevens, T., Esmon, B., Schekman, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Early+stages+in+the+yeast+secretory+pathway+are+required+for+transport+of+carboxypeptidase+Y+to+the+vacuole.">Early stages in the yeast secretory pathway are required for transport of carboxypeptidase Y to the vacuole.</a> Cell. 30, 439-448 (1982).</li><li>Novick, P., Ferro, S., Schekman, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Order+of+events+in+the+yeast+secretory+pathway.">Order of events in the yeast secretory pathway.</a> Cell. 25, 461-469 (1981).</li><li>Novick, P., Field, C., Schekman, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+of+23+complementation+groups+required+for+post-translational+events+in+the+yeast+secretory+pathway.">Identification of 23 complementation groups required for post-translational events in the yeast secretory pathway.</a> Cell. 21, 205-215 (1980).</li><li>Sopko, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mapping+pathways+and+phenotypes+by+systematic+gene+overexpression.">Mapping pathways and phenotypes by systematic gene overexpression.</a> Mol Cell. 21, 319-330 (2006).</li><li>Alberti, S., Gitler, A. D., Lindquist, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+suite+of+Gateway((R))+cloning+vectors+for+high-throughput+genetic+analysis+in+Saccharomyces+cerevisiae.">A suite of Gateway((R)) cloning vectors for high-throughput genetic analysis in Saccharomyces cerevisiae.</a> Yeast. 24, 913-919 (2007).</li><li>Gelperin, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biochemical+and+genetic+analysis+of+the+yeast+proteome+with+a+movable+ORF+collection.">Biochemical and genetic analysis of the yeast proteome with a movable ORF collection.</a> Genes Dev. 19, 2816-2826 (2005).</li><li>Hu, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Approaching+a+complete+repository+of+sequence-verified+protein-encoding+clones+for+Saccharomyces+cerevisiae.">Approaching a complete repository of sequence-verified protein-encoding clones for Saccharomyces cerevisiae.</a> Genome Res. 17, 536-543 (2007).</li><li>Giaever, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+profiling+of+the+Saccharomyces+cerevisiae+genome.">Functional profiling of the Saccharomyces cerevisiae genome.</a> Nature. 418, 387-391 (2002).</li><li>Boone, C., Bussey, H., Andrews, B. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exploring+genetic+interactions+and+networks+with+yeast.">Exploring genetic interactions and networks with yeast.</a> Nat Rev Genet. 8, 437-449 (2007).</li><li>Mnaimneh, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exploration+of+essential+gene+functions+via+titratable+promoter+alleles.">Exploration of essential gene functions via titratable promoter alleles.</a> Cell. 118, 31-44 (2004).</li><li>Parsons, A. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Integration+of+chemical-genetic+and+genetic+interaction+data+links+bioactive+compounds+to+cellular+target+pathways.">Integration of chemical-genetic and genetic interaction data links bioactive compounds to cellular target pathways.</a> Nat Biotechnol. 22, 62-69 (2004).</li><li>Schuldiner, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exploration+of+the+function+and+organization+of+the+yeast+early+secretory+pathway+through+an+epistatic+miniarray+profile.">Exploration of the function and organization of the yeast early secretory pathway through an epistatic miniarray profile.</a> Cell. 123, 507-519 (2005).</li><li>Tong, A. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Systematic+genetic+analysis+with+ordered+arrays+of+yeast+deletion+mutants.">Systematic genetic analysis with ordered arrays of yeast deletion mutants.</a> Science. 294, 2364-2368 (2001).</li><li>Tong, A. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Global+mapping+of+the+yeast+genetic+interaction+network.">Global mapping of the yeast genetic interaction network.</a> Science. 303, 808-813 (2004).</li><li>Neumann, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ubiquitinated+TDP-43+in+frontotemporal+lobar+degeneration+and+amyotrophic+lateral+sclerosis.">Ubiquitinated TDP-43 in frontotemporal lobar degeneration and amyotrophic lateral sclerosis.</a> Science. 314, 130-133 (2006).</li><li>Johnson, B. S., McCaffery, J. M., Lindquist, S., Gitler, A. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+yeast+TDP-43+proteinopathy+model:+Exploring+the+molecular+determinants+of+TDP-43+aggregation+and+cellular+toxicity.">A yeast TDP-43 proteinopathy model: Exploring the molecular determinants of TDP-43 aggregation and cellular toxicity.</a> Proc Natl Acad Sci U S A. 105, 6439-6444 (2008).</li><li>Elden, A. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ataxin-2+intermediate-length+polyglutamine+expansions+are+associated+with+increased+risk+for+ALS.">Ataxin-2 intermediate-length polyglutamine expansions are associated with increased risk for ALS.</a> Nature. 466, 1069-1075 (2010).</li><li>Johnson, B. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=TDP-43+is+intrinsically+aggregation-prone,+and+amyotrophic+lateral+sclerosis-linked+mutations+accelerate+aggregation+and+increase+toxicity.">TDP-43 is intrinsically aggregation-prone, and amyotrophic lateral sclerosis-linked mutations accelerate aggregation and increase toxicity.</a> J Biol Chem. 284, 20329-20339 (2009).</li><li>Cooper, A. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Alpha-synuclein+blocks+ER-Golgi+traffic+and+Rab1+rescues+neuron+loss+in+Parkinson's+models.">Alpha-synuclein blocks ER-Golgi traffic and Rab1 rescues neuron loss in Parkinson's models.</a> Science. 313, 324-328 (2006).</li><li>Gitler, A. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Beer+and+Bread+to+Brains+and+Beyond:+Can+Yeast+Cells+Teach+Us+about+Neurodegenerative+Disease?.">Beer and Bread to Brains and Beyond: Can Yeast Cells Teach Us about Neurodegenerative Disease?.</a> Neurosignals. 16, 52-62 (2008).</li><li>Gitler, A. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Alpha-synuclein+is+part+of+a+diverse+and+highly+conserved+interaction+network+that+includes+PARK9+and+manganese+toxicity.">Alpha-synuclein is part of a diverse and highly conserved interaction network that includes PARK9 and manganese toxicity.</a> Nat Genet. 41, 308-315 (2009).</li></ol>

Burada maya yüksek verimli bir plazmid aşırı ekspresyonu ekran gerçekleştirmek için bir protokol mevcut. Bu yaklaşım, birçok farklı hücre fenotipleri genetik nitelemeler için hızlı ve tarafsız bir tarama sağlar. Bu yaklaşımı kullanarak, bir araştırmacı, birkaç hafta içinde maya genomu önemli bir bölümünü ekrana. Bu tarafsız bir yaklaşım aynı zamanda, önceki bulgulara göre tahmin edilmiş olabilir değiştirici belirlenmesi için olanak sağlar. Biz insan nörodejeneratif hastalık pro...

<table border="1"><tbody><tr><th> Reaktif Adı </th><th> Şirket </th><th> Katalog numarası </th></tr><tr><td> BioRobot RapidPlate </td><td> Qiagen </td><td> 9000490 </td></tr><tr><td> 96 cıvata çoğaltıcı (Frogger) </td><td> V &amp; P Bilimsel </td><td> VP404 </td></tr><tr><td> FLEXGene ORF Kütüphanesi </td><td> Proteomik Enstitüsü, Harvard Tıp Fakültesi </td><td></td></tr><tr><td> Masa üstü santrifüj </td><td> Eppendorf </td><td> 5810R </td></tr><tr><td> 500ml şaşkın şişesi </td><td> Bellco </td><td> 2543-00500 </td></tr><tr><td> 2.8L üçlü şaşkın FERNBACH şişesi </td><td> Bellco </td><td> 2551-02800 </td></tr><tr><td> 100μL Rapidplate pipet uçları </td><td> Axygen </td><td> ZT-100-RS </td></tr><tr><td> 200μL Rapidplate pipet uçları </td><td> Axygen </td><td> ZT-200-RS </td></tr></tbody></table>

high-throughput yeast plasmid overexpression screen

Saccharomyces cerevisiae, tomurcuklanan bir maya, insan hastalığı ile doğrudan ilgili olanlar da dahil olmak üzere birçok önemli hücresel süreçlerin temel mekanizmaları, tanımlamak için güçlü bir model sistem. Çünkü, kısa üretim süresi ve iyi karakterize genom, maya model sistem büyük bir deneysel avantajı, belirli bir süreç içinde yer genler ve yolları belirlemek için genetik ekranlar gerçekleştirmek için yeteneğidir. Son otuz yıl içinde bu tür genetik ekranlar hücre döngüsü, salgı yolağı ve ökaryotik hücre biyolojisi 1-5 çok daha yüksek oranda korunmuş yönlerini aydınlatmak için kullanılmaktadır . Son birkaç yıl içinde, maya suşları ve plazmid birkaç genomewide kütüphaneler 6-10 oluşturuldu. Bu koleksiyon, kazanç ve kayıp fonksiyon-yaklaşımları kullanarak 11-16 genin fonksiyonu ile sistematik bir sorgulama için izin verir. Burada dizilmiş 5.500 maya plazmid bir kütüphaneyi kullanarak, plazmid aşırı ekspresyonu ekranı gerçekleştirmek için bir sıvı taşıma robotu ile yüksek verimli bir maya dönüşüm protokolü kullanımı için ayrıntılı bir protokol sağlar. Biz kümeleme eğilimli insan nörodejeneratif hastalık proteinlerin birikimi ile ilişkili toksisite genetik nitelemeler tanımlamak için bu ekranlar kullanıyoruz. Burada sunulan yöntemler diğer ilgi hücre fenotipleri çalışma kolayca uyarlanabilir.

Watch this Scientific Journal Video about High-throughput Yeast Plasmid Overexpression Screen at JoVE.com

High-throughput Yeast Plasmid Overexpression Screen

Burada bir plazmid aşırı ekspresyonu ekran tarif<em&gt; Saccharomyces cerevisiae</em&gt;, Bir sıvı taşıma robotu ile dizilmiş plazmid bir kütüphane ve yüksek verimli bir maya dönüşüm protokolü kullanarak.

Yüksek verim Maya Plazmid overekspresyonu Ekran

The budding yeast, Saccharomyces cerevisiae, is a powerful model system for defining fundamental mechanisms of many important cellular processes, ...

high-throughput-yeast-plasmid-overexpression-screen

Research

JoVE Journal

Biology

16.3K Görüntüleme.  University of Pennsylvania School of Medicine. Burada bir plazmid aşırı ekspresyonu ekran tarif Saccharomyces cerevisiae, Bir sıvı taşıma robotu ile dizilmiş plazmid bir kütüphane ve yüksek verimli bir maya dönüşüm protokolü kullanarak.

Video: High-throughput Yeast Plasmid Overexpression Screen

A High Throughput Screen for Biomining Cellulase Activity from Metagenomic Libraries

Cellulose, the most abundant source of organic carbon on the planet, has wide-ranging industrial applications with increasing emphasis on biofuel production 1. Chemical methods to modify or degrade cellulose typically require strong acids and high temperatures. As such, enzymatic methods have become prominent in the bioconversion process. While the identification of active cellulases from bacterial and fungal isolates has been somewhat effective, the vast majority of microbes in nature resist laboratory cultivation. Environmental genomic, also known as metagenomic, screening approaches have great promise in bridging the cultivation gap in the search for novel bioconversion enzymes. Metagenomic screening approaches have successfully recovered novel cellulases from environments as varied as soils 2, buffalo rumen 3 and the termite hind-gut 4 using carboxymethylcellulose (CMC) agar plates stained with congo red dye (based on the method of Teather and Wood 5). However, the CMC method is limited in throughput, is not quantitative and manifests a low signal to noise ratio 6. Other methods have been reported 7,8 but each use an agar plate-based assay, which is undesirable for high-throughput screening of large insert genomic libraries. Here we present a solution-based screen for cellulase activity using a chromogenic dinitrophenol (DNP)-cellobioside substrate 9. Our library was cloned into the pCC1 copy control fosmid to increase assay sensitivity through copy number induction 10. The method uses one-pot chemistry in 384-well microplates with the final readout provided as an absorbance measurement. This readout is quantitative, sensitive and automated with a throughput of up to 100X 384-well plates per day using a liquid handler and plate reader with attached stacking system.

This protocol describes a high throughput screen for cellulolytic activity from a metagenomic library expressed in Escherichia coli. The screen is solution based and highly automated, and uses one-pot chemistry in 384 well microplates with the final readout as an absorbance measurement.

Yüksek Verimli Ekran Metagenomic Kütüphaneler selülaz Aktivitesi Biomining

Cellulose, the most abundant source of organic carbon on the planet, has wide-ranging industrial applications with increasing emphasis on biofuel ...

Biyoloji

High-throughput Saccharification Assay for Lignocellulosic Materials

Polysaccharides that make up plant lignocellulosic biomass can be broken down to produce a range of sugars that subsequently can be 
used in establishing a biorefinery. These raw materials would constitute a new industrial platform, which is both sustainable and carbon neutral, to replace 
the current dependency on fossil fuel. The recalcitrance to deconstruction observed in lignocellulosic materials is produced by several intrinsic properties 
of plant cell walls. Crystalline cellulose is embedded in matrix polysaccharides such as xylans and arabinoxylans, and the whole structure is encased by the 
phenolic polymer lignin, that is also difficult to digest 1. In order to improve the digestibility of plant materials we need to discover the main bottlenecks 
for the saccharification of cell walls and also screen mutant and breeding populations to evaluate the variability in saccharification 2. These tasks require 
a high throughput approach and here we present an analytical platform that can perform saccharification analysis in a 96-well plate format. This platform has 
been developed to allow the screening of lignocellulose digestibility of large populations from varied plant species. We have scaled down the reaction volumes 
for gentle pretreatment, partial enzymatic hydrolysis and sugar determination, to allow large numbers to be assessed rapidly in an automated system.
This automated platform works with milligram amounts of biomass, performing ball milling under controlled conditions to reduce the plant 
materials to a standardised particle size in a reproducible manner. Once the samples are ground, the automated formatting robot dispenses specified and recorded 
amounts of material into the corresponding wells of 96 deep well plate (Figure 1). Normally, we dispense the same material into 4 wells to have 4 replicates for 
analysis. Once the plates are filled with the plant material in the desired layout, they are manually moved to a liquid handling station (Figure 2). In this 
station the samples are subjected to a mild pretreatment with either dilute acid or alkaline and incubated at temperatures of up to 90&deg;C. The pretreatment solution 
is subsequently removed and the samples are rinsed with buffer to return them to a suitable pH for hydrolysis. The samples are then incubated with an enzyme
mixture for a variable length of time at 50&deg;C. An aliquot is taken from the hydrolyzate and the reducing sugars are automatically determined by the MBTH 
colorimetric method.

A simple, rapid method for determining the saccharification potential of large numbers of plant biomass samples is described. The automated platform for this analysis involves the preparation of the plant biomass for analysis in 96 well plates and the subsequent performance of pretreatment, hydrolysis and quantification of the sugars released.

Lignocellulosic Malzemeler için Yüksek verim Saccharification Testi

Polysaccharides that make up plant lignocellulosic biomass can be broken down to produce a range of sugars that subsequently can be 
used in establishing ...

High-throughput Purification of Affinity-tagged Recombinant Proteins

X-ray crystallography is the method of choice for obtaining a detailed view of the structure of proteins. Such studies need to be complemented by further biochemical analyses to obtain detailed insights into structure/function relationships. Advances in oligonucleotide- and gene synthesis technology make large-scale mutagenesis strategies increasingly feasible, including the substitution of target residues by all 19 other amino acids. Gain- or loss-of-function phenotypes then allow systematic conclusions to be drawn, such as the contribution of particular residues to catalytic activity, protein stability and/or protein-protein interaction specificity.
In order to attribute the different phenotypes to the nature of the mutation - rather than to fluctuating experimental conditions - it is vital to purify and analyse the proteins in a controlled and reproducible manner. High-throughput strategies and the automation of manual protocols on robotic liquid-handling platforms have created opportunities to perform such complex molecular biological procedures with little human intervention and minimal error rates1-5.
Here, we present a general method for the purification of His-tagged recombinant proteins in a high-throughput manner. In a recent study, we applied this method to a detailed structure-function investigation of TFIIB, a component of the basal transcription machinery. TFIIB is indispensable for promoter-directed transcription in vitro and is essential for the recruitment of RNA polymerase into a preinitiation complex6-8. TFIIB contains a flexible linker domain that penetrates the active site cleft of RNA polymerase9-11. This linker domain confers two biochemically quantifiable activities on TFIIB, namely (i) the stimulation of the catalytic activity during the 'abortive' stage of transcript initiation, and (ii) an additional contribution to the specific recruitment of RNA polymerase into the preinitiation complex4,5,12 . We exploited the high-throughput purification method to generate single, double and triple substitution and deletions mutations within the TFIIB linker and to subsequently analyse them in functional assays for their stimulation effect on the catalytic activity of RNA polymerase4. Altogether, we generated, purified and analysed 381 mutants - a task which would have been time-consuming and laborious to perform manually. We produced and assayed the proteins in multiplicates which allowed us to appreciate any experimental variations and gave us a clear idea of the reproducibility of our results.
This method serves as a generic protocol for the purification of His-tagged proteins and has been successfully used to purify other recombinant proteins. It is currently optimised for the purification of 24 proteins but can be adapted to purify up to 96 proteins.

We describe a method for the affinity-tagged purification of recombinant proteins using liquid-handling robotics. This method is generally applicable to the small-scale purification of soluble His-tagged proteins in a high-throughput format.

Affinity etiketli Rekombinant Proteinler Yüksek throughput Arıtma

X-ray crystallography is the method of choice for obtaining a detailed view of the structure of proteins. Such studies need to be complemented by further ...

RNA Secondary Structure Prediction Using High-throughput SHAPE

Understanding the function of RNA involved in biological processes requires a thorough knowledge of RNA structure. Toward this end, the methodology dubbed "high-throughput selective 2' hydroxyl acylation analyzed by primer extension", or SHAPE, allows prediction of RNA secondary structure with single nucleotide resolution. This approach utilizes chemical probing agents that preferentially acylate single stranded or flexible regions of RNA in aqueous solution. Sites of chemical modification are detected by reverse transcription of the modified RNA, and the products of this reaction are fractionated by automated capillary electrophoresis (CE). Since reverse transcriptase pauses at those RNA nucleotides modified by the SHAPE reagents, the resulting cDNA library indirectly maps those ribonucleotides that are single stranded in the context of the folded RNA. Using ShapeFinder software, the electropherograms produced by automated CE are processed and converted into nucleotide reactivity tables that are themselves converted into pseudo-energy constraints used in the RNAStructure (v5.3) prediction algorithm. The two-dimensional RNA structures obtained by combining SHAPE probing with in silico RNA secondary structure prediction have been found to be far more accurate than structures obtained using either method alone.

High-throughput selective 2' hydroxyl acylation analyzed by primer extension (SHAPE) utilizes a novel chemical probing technology, reverse transcription, capillary electrophoresis and secondary structure prediction software to determine the structures of RNAs from several hundred to several thousand nucleotides at single nucleotide resolution.

Yüksek verim SHAPE kullanarak RNA İkincil Yapısı Tahmin

Understanding the function of RNA involved in biological processes requires a thorough knowledge of RNA structure. Toward this end, the methodology dubbed ...

High Throughput Microinjections of Sea Urchin Zygotes

Microinjection into cells and embryos is a common technique that is used to study a wide range of biological processes. In this method a small amount of treatment solution is loaded into a microinjection needle that is used to physically inject individual immobilized cells or embryos. Despite the need for initial training to perform this procedure for high-throughput delivery, microinjection offers maximum efficiency and reproducible delivery of a wide variety of treatment solutions (including complex mixtures of samples) into cells, eggs or embryos. Applications to microinjections include delivery of DNA constructs, mRNAs, recombinant proteins, gain of function, and loss of function reagents. Fluorescent or colorimetric dye is added to the injected solution to enable instant visualization of efficient delivery as well as a tool for reliable normalization of the amount of the delivered solution. The described method enables microinjection of 100-400 sea urchin zygotes within 10-15 min.

Microinjection is a common technique used to deliver DNA constructs, mRNAs, morpholino antisense oligonucleotides or other treatments into eggs, embryos, and cells of various species.

Deniz Kestanesi Zigotlar Yüksek Randımanlı Microinjections

Microinjection into cells and embryos is a common technique that is used to study a wide range of biological processes. In this method a small amount of ...

High-throughput Titration of Luciferase-expressing Recombinant Viruses

Standard plaque assays to determine infectious viral titers can be time consuming, are not amenable to a high volume of samples, and cannot be done with viruses that do not form plaques. As an alternative to plaque assays, we have developed a high-throughput titration method that allows for the simultaneous titration of a high volume of samples in a single day. This approach involves infection of the samples with a Firefly luciferase tagged virus, transfer of the infected samples onto an appropriate permissive cell line, subsequent addition of luciferin, reading of plates in order to obtain luminescence readings, and finally the conversion from luminescence to viral titers. The assessment of cytotoxicity using a metabolic viability dye can be easily incorporated in the workflow in parallel and provide valuable information in the context of a drug screen. This technique provides a reliable, high-throughput method to determine viral titers as an alternative to a standard plaque assay.

This article presents a high-throughput luciferase expression-based method of titrating various RNA and DNA viruses using automated and manual liquid handlers.

Lusiferaz ifade eden rekombinant virüsler yüksek verimlilik Titrasyon

Standard plaque assays to determine infectious viral titers can be time consuming, are not amenable to a high volume of samples, and cannot be done with ...

A Manual Small Molecule Screen Approaching High-throughput Using Zebrafish Embryos

Zebrafish have become a widely used model organism to investigate the mechanisms that underlie developmental biology and to study human disease pathology due to their considerable degree of genetic conservation with humans. Chemical genetics entails testing the effect that small molecules have on a biological process and is becoming a popular translational research method to identify therapeutic compounds. Zebrafish are specifically appealing to use for chemical genetics because of their ability to produce large clutches of transparent embryos, which are externally fertilized. Furthermore, zebrafish embryos can be easily drug treated by the simple addition of a compound to the embryo media. Using whole-mount in situ hybridization (WISH), mRNA expression can be clearly visualized within zebrafish embryos. Together, using chemical genetics and WISH, the zebrafish becomes a potent whole organism context in which to determine the cellular and physiological effects of small molecules. Innovative advances have been made in technologies that utilize machine-based screening procedures, however for many labs such options are not accessible or remain cost-prohibitive. The protocol described here explains how to execute a manual high-throughput chemical genetic screen that requires basic resources and can be accomplished by a single individual or small team in an efficient period of time. Thus, this protocol provides a feasible strategy that can be implemented by research groups to perform chemical genetics in zebrafish, which can be useful for gaining fundamental insights into developmental processes, disease mechanisms, and to identify novel compounds and signaling pathways that have medically relevant applications.

The zebrafish is an excellent experimental organism to study vertebrate developmental processes and model human disease. Here, we describe a protocol on how to perform a manual high-throughput chemical screen in zebrafish embryos with a whole-mount in situ hybridization (WISH) read-out.

Zebra balığı Embriyolar kullanılarak Yüksek verim Yaklaşıyor A Manuel Küçük Molekül Ekran

Zebrafish have become a widely used model organism to investigate the mechanisms that underlie developmental biology and to study human disease pathology ...

Recovery of Adult Zebrafish Hearts for High-throughput Applications

Use of the zebrafish model system for studying development, regeneration, and disease is expanding toward use of adult hearts for cell dissociation and purification of RNA, DNA, and proteins. All of these applications demand the rapid recovery of significant numbers of zebrafish hearts to avoid gene regulatory, metabolic, and other changes that begin after death. Adult zebrafish hearts are also required for studying heart structure for a variety of mutants and for studying heart regeneration. However, the traditional zebrafish heart dissection is slow and difficult and requires specialized tools, making large-scale dissection of adult zebrafish hearts tedious. Traditional methods also harbor the risk of damaging the heart during the dissection. Here, we describe a method for dissection of adult zebrafish hearts that is fast, reproducible, and preserves heart architecture. Furthermore, this method does not require specialized tools, is painless for the zebrafish, can be performed on fresh or fixed specimens, and can be performed on zebrafish as young as one month old. The approach described expands the use of adult zebrafish for cardiovascular research.

Use of zebrafish for cardiovascular research is expanding towards research on adult hearts. For these applications, quick and simple isolation of cardiac tissues is key to avoid post-mortem changes and to obtain an adequate number of samples. Here, we describe a fast and reproducible method for dissecting adult zebrafish hearts.

Yüksek verim Uygulamaları Yetişkin Zebra Hearts Kurtarma

Use of the zebrafish model system for studying development, regeneration, and disease is expanding toward use of adult hearts for cell dissociation and ...

High-throughput Screening for Chemical Modulators of Post-transcriptionally Regulated Genes

Both transcriptional and post-transcriptional regulation have a profound impact on genes expression. However, commonly adopted cell-based screening assays focus on transcriptional regulation, being essentially aimed at the identification of promoter-targeting molecules. As a result, post-transcriptional mechanisms are largely uncovered by gene expression targeted drug development. Here we describe a cell-based assay aimed at investigating the role of the 3&#39; untranslated region (3&#8217; UTR) in the modulation of the fate of its mRNA, and at identifying compounds able to modify it. The assay is based on the use of a luciferase reporter construct containing the 3&#8217; UTR of a gene of interest stably integrated into a disease-relevant cell line. The protocol is divided into two parts, with the initial focus on the primary screening aimed at the identification of molecules affecting luciferase activity after 24 hr of treatment. The second part of the protocol describes the counter-screening necessary to discriminate compounds modulating luciferase activity specifically through the 3&#8217; UTR. In addition to the detailed protocol and representative results, we provide important considerations about the assay development and the validation of the hit(s) on the endogenous target. The described cell-based reporter gene assay will allow scientists to identify molecules modulating protein levels via post-transcriptional mechanisms dependent on a 3&#8217; UTR.

Here we describe a cell-based reporter gene assay as a valuable tool to screen chemical libraries for compounds modulating post-transcriptional control mechanisms exerted through 3&#8217; UTR.

Post-transkripsiyonel ayarlı genlerin kimyasal Modülatörler için yüksek verimli tarama

Both transcriptional and post-transcriptional regulation have a profound impact on genes expression. However, commonly adopted cell-based screening assays ...

High Throughput Danio Rerio Energy Expenditure Assay

Zebrafish are an important model organism with inherent advantages that have the potential to make zebrafish a widely applied model for the study of energy homeostasis and obesity. The small size of zebrafish allows for assays on embryos to be conducted in a 96- or 384-well plate format, Morpholino and CRISPR based technologies promote ease of genetic manipulation, and drug treatment by bath application is viable. Moreover, zebrafish are ideal for forward genetic screens allowing for novel gene discovery. Given the relative novelty of zebrafish as a model for obesity, it is necessary to develop tools that fully exploit these benefits. Herein, we describe a method to measure energy expenditure in thousands of embryonic zebrafish simultaneously. We have developed a whole animal microplate platform in which we use 96-well plates to isolate individual fish and we assess cumulative NADH2 production using the commercially available cell culture viability reagent alamarBlue. In poikilotherms the relationship between NADH2 production and energy expenditure is tightly linked. This energy expenditure assay creates the potential to rapidly screen pharmacological or genetic manipulations that directly alter energy expenditure or alter the response to an applied drug (e.g. insulin sensitizers).

High Throughput Danio Rerio Energy Expenditure Assay

Zebrafish are an important model organism for the study of energy homeostasis. By utilizing a NADH2 sensitive redox indicator, alamar Blue, we have developed an assay that measures the metabolic rate of zebrafish larvae in a 96 well plate format and can be applied to drug or gene discovery.

Yüksek Verimli<em&gt; Danio rerio</em&gt; Enerji Harcaması Deneyi

Zebrafish are an important model organism with inherent advantages that have the potential to make zebrafish a widely applied model for the study of ...