תיוג, הכלאה, ופרוטוקולים כביסה בזאת להכיל כמה שינויים אלה פיתחה בעבר ואילו במכון לחקר הגנום (TIGR), ד&quot;ר שון לוי ב microarray ונדרבילט משאבים משותפים (VMSR) על ידי ד&quot;ר י Quackenbush, וד&quot;ר רוב אלבה תוך תומפסון בויס המכון, (BTI) מאוניברסיטת קורנל.

<ol>
	<li>Lorenz, W. W., Sun, F., Liang, C., Kolychev, D., Wang, H., Zhao, X., Cordonnier-Pratt, M. M., Pratt, L. H., Dean, J. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Water+stress-responsive+genes+in+loblolly+pine+(Pinus+taeda)+roots+identified+by+analyses+of+expressed+sequence+tag+libraries.">Water stress-responsive genes in loblolly pine (Pinus taeda) roots identified by analyses of expressed sequence tag libraries.</a> Tree Physiol. 26, 1-16 (2006).</li><li>Lorenz, W. W., Dean, J. F. 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> unpublished data. , .</li><li>Hegde, P., Qi, R., Abernathy, K., Gay, C., Dharap, S., Gaspard, R., Hughes, J. E., Snesrud, E., Lee, N., Quackenbush, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+concise+guide+to+cDNA+microarray+analysis.">A concise guide to cDNA microarray analysis.</a> Biotechniques. 29, 548-562 (2000).</li><li>Alba, R., Fei, Z., Payton, P., Liu, Y., Moore, S. L., Debbie, P., Cohn, J., D'Ascenzo, M., Gordon, J. S., Rose, J. K. C., Martin, G., Tanksley, S. D., Bouzayen, M., Molly, M., Jahn, M. M., Giovannoni, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ESTs,+cDNA+microarrays,+and+gene+expression+profiling:+tools+for+dissecting+plant+physiology+and+development.">ESTs, cDNA microarrays, and gene expression profiling: tools for dissecting plant physiology and development.</a> The Plant Journal. 39, 697-714 (2004).</li><li>Lorenz, W. W., Simões, M., Miguel, C., Dean, J. F. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+Gene+Expression+changes+in+Pinus+species+using+a+Loblolly+pine+cDNA+microarray.">Analysis of Gene Expression changes in Pinus species using a Loblolly pine cDNA microarray.</a> IUFRO-CTIA 2008 Joint Conference. , (2008).</li><li>Simões, M., Lorenz, W. W., Alba, A., Gonçalves, S., Dean, J., Miguel, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Global+gene+expression+analysis+during+P.+pinaster+embryo+development.">Global gene expression analysis during P. pinaster embryo development.</a> 7th Plant Genomics European Meeting. , (2008).</li></ol>

PtGen2 היא פיתחה לאחרונה, cDNA microarray מותאם אישית נועד לשמש בעיקר על ידי הקהילה אורן loblolly מחקר. תוצאות ראשוניות שנוצר עד כה הראו את מערך להיות כלי חשוב בהערכת תעתיק אירועים המתרחשים בתגובה ללחץ בצורת, כמו גם ניטור השינויים המתרחשים במהלך התפתחות העובר בתוך הימי אורן, Pinus p...

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<td>Pre-hybridization Buffer</td>
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processing the loblolly pine ptgen2 cdna microarray

PtGen2 הוא cDNA microarray 26,496 תכונה המכיל מוגבר אורן ESTs loblolly. מערך מיוצר במעבדה שלנו לשימוש על ידי חוקרים לומד ביטוי גנים במינים כוניפאר אורן אחרים. PtGen2 פותחה בעקבות גילוי הגן שלנו מאמצים אורן loblolly, והוא מורכב רצפים מזוהים בעיקר לרקמות השורש, אלא גם מן המחט גזע. 1,2 PtGen2 נבדק על ידי והכלאה שונים סיי-צבע שכותרתו cDNAs כוניפאר היעד , הן באמצעות מוגבר ולא מוגבר בשיטות תיוג עקיף, נבדק גם עם מספר תנאים הכלאה ושטיפת. וידאו זה מתמקד בטיפול ועיבוד של שקופיות לפני ואחרי הכלאה מראש, כמו גם לאחר הכלאה, בעזרת כמה שינויים הנהלים שפותחו בעבר. 3,4 כמו כן, בצורת טקסט בלבד, הם הפרוטוקולים המשמשים הדור, תיוג ולנקות של cDNA של היעד, כמו גם מידע על תוכנה המשמשת לעיבוד נתונים במורד הזרם. PtGen2 מודפס עם חיץ להדפיס קניינית המכילה ריכוזים גבוהים של מלח זה יכול להיות קשה להסיר לחלוטין. השקופיות נשטפים הראשון לפתרון SDS חמים לפני הכלאה מראש. לאחר הכלאה מראש, השקופיות נשטפים במרץ כמה שינויים של מים כדי להשלים את הסרת מלחים הנותרים. LifterSlips ™ מנקים אז וממוקמים על השקופיות ומסומן cDNA נטען בזהירות בדרך של פעולה נימי המספק להפצה גם של המדגם על פני השקופית על microarray, ומקטין את הסיכוי ההתאגדות בועה. הכלאה של מטרות למערך נעשית על 48 מעלות צלזיוס בתנאי לחות גבוהה. לאחר ההכלאה, בסדרה של שוטף רגיל נעשים על 53 מעלות צלזיוס בטמפרטורת החדר במשך פעמים המורחבת. עיבוד PtGen2 שקופיות באמצעות טכניקה זו מפחיתה מלח SDS-derived חפצים נראים לעתים קרובות כאשר מערך מעובד פחות קפדני. והכלאה מטרות הנגזרות מספר מקורות שונים כוניפאר RNA, פרוטוקול זה הניב ממצאים פחות עיבוד, רקע מופחת, ובלבד עקביות טוב יותר בין קבוצות הניסוי שונים של מערכים.

Watch this Scientific Journal Video about Processing the Loblolly Pine PtGen2 cDNA Microarray at JoVE.com

Processing the Loblolly Pine PtGen2 cDNA Microarray

CDNA microarray PtGen2 פותחה ללימודי ביטוי גנים אורן loblolly,<em&gt; פ &#39; taeda</em&gt;, כוניפאר ומינים אחרים. כאן, אנו מציגים טרום ופוסט הכלאה הטיפול כביסה טכניקות שיכולות לשמש עם מערך זה להניב יותר עקביות, חפצים מופחת, ועל רקע נמוך.

עיבוד פיין Loblolly PtGen2 cDNA microarray

PtGen2 is a 26,496 feature cDNA microarray containing amplified loblolly pine ESTs.  The array is produced in our laboratory for use by researchers ...

processing-the-loblolly-pine-ptgen2-cdna-microarray

Universidad de Cartagena UDEC

Research

JoVE Journal

Biology

7.3K Views.  University of Georgia (UGA). CDNA microarray PtGen2 פותחה ללימודי ביטוי גנים אורן loblolly, פ ' taeda, כוניפאר ומינים אחרים. כאן, אנו מציגים טרום ופוסט הכלאה הטיפול כביסה טכניקות שיכולות לשמש עם מערך זה להניב יותר עקביות, חפצים מופחת, ועל רקע נמוך.

Video: Processing the Loblolly Pine PtGen2 cDNA Microarray

Gibberella zeae Ascospore Production and Collection for Microarray Experiments.

Fusarium graminearum Schwabe (teleomorph Gibberella zeae) is a plant pathogen causing scab disease on wheat and barley that reduces crop yield and grain quality. F. graminearum also causes stalk and ear rots of maize and is a producer of mycotoxins such as the trichothecenes that contaminate grain and are harmful to humans and livestock (Goswami and Kistler, 2004).

The fungus produces two types of spores. Ascospores, the propagules resulting from sexual reproduction, are the main source of primary infection.  These spores are forcibly discharged from mature perithecia and dispersed by wind (Francl et al 1999). Secondary infections are mainly caused by macroconidia which are produced by asexual means on the plant surface. To study the developmental processes of ascospores in this fungus, a procedure for their collection in large quantity under sterile conditions was required. Our protocol was filmed in order to generate the highest level of information for understanding and reproducibility; crucial aspects when full genome gene expression profiles are generated and interpreted. In particular, the variability of ascospore germination and biological activity are dependent on the prior manipulation of the material. The use of video for documenting every step in ascospore production is proposed in order to increase standardization, complying with the increasingly stringent requirements for microarray analysis. The procedure requires only standard laboratory equipment. Steps are shown to prevent contamination and favor time synchronization of ascospores.

To study the developmental processes of ascospores in Gibberella zeae, a procedure for collection under sterile conditions is filmed in order to generate the highest level of information for protocol description. This should facilitate the reproducibility of the experiment, a crucial aspect when full genome expression profile tests are implemented.

Gibberella zeae Ascospore ייצור אוסף לניסויים microarray.

Fusarium graminearum Schwabe (teleomorph Gibberella zeae) is a plant pathogen causing scab disease on wheat and barley that reduces crop yield and grain ...

The Microfluidic Probe: Operation and Use for Localized Surface Processing

Microfluidic devices allow assays to be performed using minute amounts of sample and have recently been used to control the microenvironment of cells. Microfluidics is commonly associated with closed microchannels which limit their use to samples that can be introduced, and cultured in the case of cells, within a confined volume. On the other hand, micropipetting system have been used to locally perfuse cells and surfaces, notably using push-pull setups where one pipette acts as source and the other one as sink, but the confinement of the flow is difficult in three dimensions. Furthermore, pipettes are fragile and difficult to position and hence are used in static configuration only. 
The microfluidic probe (MFP) circumvents the constraints imposed by the construction of closed microfluidic channels and instead of enclosing the sample into the microfluidic system, the microfluidic flow can be directly delivered onto the sample, and scanned across the sample, using the MFP. . The injection and aspiration openings are located within a few tens of micrometers of one another so that a microjet injected into the gap is confined by the hydrodynamic forces of the surrounding liquid and entirely aspirated back into the other opening. The microjet can be flushed across the substrate surface and provides a precise tool for localized deposition/delivery of reagents which can be used over large areas by scanning the probe across the surface. 
In this video we present the microfluidic probe1 (MFP). We explain in detail how to assemble the MFP, mount it atop an inverted microscope, and align it relative to the substrate surface, and finally show how to use it to process a substrate surface immersed in a buffer.

In this video we present the microfluidic probe1 (MFP). We explain in detail how to assemble the MFP, mount it atop an inverted microscope, and align it relative to the substrate surface, and finally show how to use it to process a substrate surface immersed in a buffer solution.

בדיקה Microfluidic: מבצע ושימוש לעיבוד Surface לוקליזציה

Microfluidic devices allow assays to be performed using minute amounts of sample and have recently been used to control the microenvironment of cells. ...

RNA Isolation from Embryonic Zebrafish and cDNA Synthesis for Gene Expression Analysis

Many important and complex laboratory procedures require an input of high quality, intact RNA.  A degraded sample or the presence of impurities can lead to disastrous results in downstream experimental applications.  It is therefore, of utmost importance to use solid techniques with numerous safeguards and quality control checks to ensure a superior sample.  Herein, we detail a protocol to isolate total RNA from whole zebrafish embryos using a commercially available chemical denaturant and subsequent cleanup to remove traces of DNA and impurities using a commercial RNA isolation kit. As RNA is relatively unstable and easily prone to cleavage by RNAses, most protocols assay gene expression using a cDNA product that is directly synthesized from an RNA template. We detail a procedure to convert RNA into the more stable cDNA product using a commercially available kit. Throughout these procedures there are numerous quality control checks to ensure that the sample is not degraded or contaminated.  The end product of these protocols is cDNA that is suitable for microarray analysis, RT-PCR or long-term storage.    

The isolation of high quality, intact RNA is an essential step in many laboratory protocols. Here, we demonstrate RNA extraction from whole zebrafish embryos and cDNA synthesis for subsequent application in various experimental procedures including gene expression microarray analysis.

RNA סינתזה ניתוק מן דג הזברה cDNA עובריים עבור ניתוח ביטוי גנים

Many important and complex laboratory procedures require an input of high quality, intact RNA.  A degraded sample or the presence of impurities can lead ...

Global Gene Expression Analysis Using a Zebrafish Oligonucleotide Microarray Platform

Gene microarray technology permits quantitative measurement and gene expression profiling of transcript levels on a genome-wide basis. Gene microarray technology is used in numerous biological disciplines in a variety of applications including global gene expression analysis in relation to developmental stage, to a disease state, and in toxic responses. Herein, we include a demonstration of global gene expression analysis using a comprehensive zebrafish-specific oligonucleotide microarray platform. The zebrafish expression microarray platform contains 385,000 probes, 60 base pairs in length, interrogating 37,157 targets with up to 12 probes per target. For this platform, all cDNA and genomic information available for the zebrafish was collected from various genomic databases including Ensembl (http://www.ensembl.org), VEGA (http://vega.sanger.ac.uk), UCSC (http://genome.ucsc.edu), and ZFIN (http://www.zfin.org). As a result this expression array provides complete coverage of the current zebrafish transcriptome. The zebrafish expression microarray was printed by Roche NimbleGen (Madison, WI). This technical demonstration includes the fluorescent labeling of a cDNA product, hybridization of the labeled cDNA product to the microarray platform, and array scanning for signal acquisition using the one color analysis strategy.  

Gene microarrays are powerful tools in gene expression profiling at a genome-wide level. This technology has application in a variety of biological disciplines including developmental biology and toxicology. In this video, we detail a protocol for global gene expression analysis using a comprehensive oligonucleotide microarray platform for the zebrafish.

Gene Expression גלובל ניתוח באמצעות פלטפורמה דג הזברה microarray oligonucleotide

Gene microarray technology permits quantitative measurement and gene expression profiling of transcript levels on a genome-wide basis. Gene microarray ...

Digital Microfluidics for Automated Proteomic Processing

Clinical proteomics has emerged as an important new discipline, promising the discovery of biomarkers that will be useful for early diagnosis and prognosis of disease. While clinical proteomic methods vary widely, a common characteristic is the need for (i) extraction of proteins from extremely heterogeneous fluids (i.e. serum, whole blood, etc.) and (ii) extensive biochemical processing prior to analysis. Here, we report a new digital microfluidics (DMF) based method integrating several processing steps used in clinical proteomics. This includes protein extraction, resolubilization, reduction, alkylation and enzymatic digestion. Digital microfluidics is a microscale fluid-handling technique in which nanoliter-microliter sized droplets are manipulated on an open surface. Droplets are positioned on top of an array of electrodes that are coated by a dielectric layer - when an electrical potential is applied to the droplet, charges accumulate on either side of the dielectric. The charges serve as electrostatic handles that can be used to control droplet position, and by biasing a sequence of electrodes in series, droplets can be made to dispense, move, merge, mix, and split on the surface. Therefore, DMF is a natural fit for carrying rapid, sequential, multistep, miniaturized automated biochemical assays. This represents a significant advance over conventional methods (relying on manual pipetting or robots), and has the potential to be a useful new tool in clinical proteomics.
Mais J. Jebrail, Vivienne N. Luk, and Steve C. C. Shih contributed equally to this work.
Sergio L. S. Freire's current address is at the University of the Sciences in Philadelphia located at 600 South 43rd Street, Philadelphia, PA 19104.

Digital Microfluidics is a technique characterized by the manipulation of discrete droplets (~nL - mL) on an array of electrodes by the application of electrical fields. It is well-suited for carrying out rapid, sequential, miniaturized automated biochemical assays. Here, we report a platform capable of automating several proteomic processing steps.

מיקרופלואידיקה דיגיטלי עבור עיבוד אוטומטי proteomic

Clinical proteomics has emerged as an important new discipline, promising the discovery of biomarkers that will be useful for early diagnosis and ...

An Improved Method of RNA Isolation from Loblolly Pine (P. taeda L.) and Other Conifer Species

Tissues isolated from conifer species, particularly those belonging to the Pinaceae family, such as loblolly pine (Pinus taeda L.), contain high concentrations of phenolic compounds and polysaccharides that interfere with RNA purification. Isolation of high-quality RNA from these species requires rigorous tissue collection procedures in the field and the employment of an RNA isolation protocol comprised of multiple organic extraction steps in order to isolate RNA of sufficient quality for microarray and other genomic analyses. The isolation of high-quality RNA from field-collected loblolly pine samples can be challenging, but several modifications to standard tissue and RNA isolation procedures greatly improve results. The extent of general RNA degradation increases if samples are not properly collected and transported from the field, especially during large-scale harvests. Total RNA yields can be increased significantly by pulverizing samples in a liquid nitrogen freezer mill prior to RNA isolation, especially when samples come from woody tissues. This is primarily due to the presence of oxidizing agents, such as phenolic compounds, and polysaccharides that are both present at high levels in extracts from the woody tissues of most conifer species. If not removed, these contaminants can carry over leading to problems, such as RNA degradation, that result in low yields and a poor quality RNA sample. Carryover of phenolic compounds, as well as polysaccharides, can also reduce or even completely eliminate the activity of reverse transcriptase or other polymerases commonly used for cDNA synthesis. In particular, RNA destined to be used as template for double-stranded cDNA synthesis in the generation of cDNA libraries, single-stranded cDNA synthesis for PCR or qPCR's, or for the synthesis of microarray target materials must be of the highest quality if researchers expect to obtain optimal results. RNA isolation techniques commonly employed for many other plant species are often insufficient in their ability to remove these contaminants from conifer samples and thus do not yield total RNA samples suitable for downstream manipulations. In this video we demonstrate methods for field collection of conifer tissues, beginning with the felling of a forty year-old tree, to the harvesting of phloem, secondary xylem, and reaction wood xylem. We also demonstrate an RNA isolation protocol that has consistently yielded high-quality RNA for subsequent enzymatic manipulations.

An Improved Method of RNA Isolation from Loblolly Pine P. taeda L. and Other Conifer Species

Many plant tissues, including phloem and xylem from loblolly pine (Pinus taeda L.), contain high levels of phenolics and polysaccharides that interfere with RNA purification. This presentation discusses techniques for the harvest of field-grown tissues and isolation of RNA of sufficient quality for microarrays and other genomic analyses.

שיטה משופרת של בידוד RNA מן אורן Loblolly ( פ &#39; taeda ל) ומינים אחרים Conifer

Tissues isolated from conifer species, particularly those belonging to the Pinaceae family, such as loblolly pine (Pinus taeda L.), contain high ...

Microarray Analysis for Saccharomyces cerevisiae

In this protocol, gene expression in yeast (Saccharomyces cerevisiae) is changed after exposure to oxidative stress induced by the addition of hydrogen peroxide (H2O2), an oxidizing agent. In the experiment, yeast is grown for 48 hours in 1/2X YPD broth containing 3X glucose. The culture is split into a control and treated group. The experiment culture is treated with 0.5 mM H2O2 in Hanks Buffered Saline (HBSS) for 1 hour. The control culture is treated with HBSS only. Total RNA is extracted from both cultures and is converted to a biotin-labeled cRNA product through a multistep process. The final synthesis product is taken back to the UVM Microarray Core Facility and hybridized to the Affymetrix yeast GeneChips. The resulting gene expression data are uploaded into bioinformatics data analysis software.

Microarray Analysis for Saccharomyces cerevisiae

In this protocol, gene expression in yeast (Saccharomyces cerevisiae) is changed after exposure to oxidative stress induced by the addition of hydrogen peroxide (H2O2), an oxidizing agent.

Microarray ניתוח עבור Saccharomyces cerevisiae</em

In this protocol, gene expression in yeast (Saccharomyces cerevisiae) is changed after exposure to oxidative stress induced by the addition of hydrogen ...

Performing Custom MicroRNA Microarray Experiments

microRNAs (miRNAs) are a large family of &tilde; 22 nucleotides (nt) long RNA molecules that are widely expressed in eukaryotes 1. Complex genomes encode at least hundreds of miRNAs, which primarily inhibit the expression of a vast number of target genes post-transcriptionally 2, 3. miRNAs control a broad range of biological processes 1. In addition, altered miRNA expression has been associated with human diseases such as cancers, and miRNAs may serve as biomarkers for diseases and prognosis 4, 5. It is important, therefore, to understand the expression and functions of miRNAs under many different conditions.
Three major approaches have been employed to profile miRNA expression: real-time PCR, microarray, and deep sequencing. The technique of miRNA microarray has the advantage of being high-throughput, generally less expensive, and most of the experimental and analysis steps can be carried out in a molecular biology laboratory at most universities, medical schools and associated hospitals. Here, we describe a method for performing custom miRNA microarray experiments. A miRNA probe set will be printed on glass slides to produce miRNA microarrays. RNA is isolated using a method or reagent that preserves small RNA species, and then labeled with a fluorescence dye. As a control, reference DNA oligonucleotides corresponding to a subset of miRNAs are also labeled with a different fluorescence dye. The reference DNA will serve to demonstrate the quality of the slide and hybridization and will also be used for data normalization. The RNA and DNA are mixed and hybridized to a microarray slide containing probes for most of the miRNAs in the database. After washing, the slide is scanned to obtain images, and intensities of the individual spots quantified. These raw signals will be further processed and analyzed as the expression data of the corresponding miRNAs. Microarray slides can be stripped and regenerated to reduce the cost of microarrays and to enhance the consistency of microarray experiments. The same principles and procedures are applicable to other types of custom microarray experiments.

A simple procedure of performing custom microRNA microarray experiments is described. The steps include isolating RNA, labeling RNA and reference DNA, hybridizing the samples to microarrays, scanning the microarrays, quantifying and analyzing hybridization signals.

ביצוע ניסויים אישית microarray MicroRNA

microRNAs (miRNAs) are a large family of &tilde; 22 nucleotides (nt) long RNA molecules that are widely expressed in eukaryotes 1.  Complex genomes encode ...

Generation of Stable Human Cell Lines with Tetracycline-inducible (Tet-on) shRNA or cDNA Expression

A major approach in the field of mammalian cell biology is the manipulation of the expression of genes of interest in selected cell lines, with the aim to reveal one or several of the gene's function(s) using transient/stable overexpression or knockdown of the gene of interest. Unfortunately, for various cell biological investigations this approach is unsuitable when manipulations of gene expression result in cell growth/proliferation defects or unwanted cell differentiation. Therefore, researchers have adapted the Tetracycline repressor protein (TetR), taken from the E. coli tetracycline resistance operon1, to generate very efficient and tight regulatory systems to express cDNAs in mammalian cells2,3. In short, TetR has been modified to either (1) block initiation of transcription by binding to the Tet-operator (TO) in the promoter region upon addition of tetracycline (termed Tet-off system) or (2) bind to the TO in the absence of tetracycline (termed Tet-on system) (Figure 1). Given the inconvenience that the Tet-off system requires the continuous presence of tetracycline (which has a half-life of about 24 hr in tissue cell culture medium) the Tet-on system has been more extensively optimized, resulting in the development of very tight and efficient vector systems for cDNA expression as used here.
Shortly after establishment of RNA interference (RNAi) for gene knockdown in mammalian cells4, vectors expressing short-hairpin RNAs (shRNAs) were described that function very similar to siRNAs5-11. However, these shRNA-mediated knockdown approaches have the same limitation as conventional knockout strategies, since stable depletion is not feasible when gene targets are essential for cellular survival. To overcome this limitation, van de Wetering et al.12 modified the shRNA expression vector pSUPER5 by inserting a TO in the promoter region, which enabled them to generate stable cell lines with tetracycline-inducible depletion of their target genes of interest.
Here, we describe a method to efficiently generate stable human Tet-on cell lines that reliably drive either inducible overexpression or depletion of the gene of interest. Using this method, we have successfully generated Tet-on cell lines which significantly facilitated the analysis of the MST/hMOB/NDR cascade in centrosome13,14 and apoptosis signaling15,16. In this report, we describe our vectors of choice, in addition to describing the two consecutive manipulation steps that are necessary to efficiently generate human Tet-on cell lines (Figure 2). Moreover, besides outlining a protocol for the generation of human Tet-on cell lines, we will discuss critical aspects regarding the technical procedures and the characterization of Tet-on cells.

Generation of Stable Human Cell Lines with Tetracycline-inducible Tet-on shRNA or cDNA Expression

A rapid and simple way to generate human cell lines with inducible and reversible cDNA overexpression or shRNA-mediated knock-down of the gene of interest. This method enables researchers to reliably and highly reproducibly manipulate cell lines that are difficult to alter by transient transfection methods or conventional knockdown/knockout strategies.

דור של שורות תאים אנושיות יציבות עם טטרציקלין-מושרה (ט ב) shRNA או ביטוי cDNA

A major approach in  the field of mammalian cell biology is the manipulation of the expression of  genes of interest in selected cell lines, with the aim ...

Analysis of RNA Processing Reactions Using Cell Free Systems: 3' End Cleavage of Pre-mRNA Substrates in vitro

The 3&#8217; end of mammalian mRNAs is not formed by abrupt termination of transcription by RNA polymerase II (RNPII). Instead, RNPII synthesizes precursor mRNA beyond the end of mature RNAs, and an active process of endonuclease activity is required at a specific site. Cleavage of the precursor RNA normally occurs 10-30 nt downstream from the consensus polyA site (AAUAAA) after the CA dinucleotides. Proteins from the cleavage complex, a multifactorial protein complex of approximately 800 kDa, accomplish this specific nuclease activity. Specific RNA sequences upstream and downstream of the polyA site control the recruitment of the cleavage complex. Immediately after cleavage, pre-mRNAs are polyadenylated by the polyA polymerase (PAP) to produce mature stable RNA messages.
Processing of the 3&#8217; end of an RNA transcript may be studied using cellular nuclear extracts with specific radiolabeled RNA substrates. In sum, a long 32P-labeled uncleaved precursor RNA is incubated with nuclear extracts in vitro, and cleavage is assessed by gel electrophoresis and autoradiography. When proper cleavage occurs, a shorter 5&#8217; cleaved product is detected and quantified. Here, we describe the cleavage assay in detail using, as an example, the 3&#8217; end processing of HIV-1 mRNAs.

Analysis of RNA Processing Reactions Using Cell Free Systems: 3' End Cleavage of Pre-mRNA Substrates in vitro

RNA polymerase II synthesizes a precursor RNA that extends beyond the 3' end of the mature mRNA. The end of the mature RNA is generated cotranscriptionally, at a site dictated by RNA sequences, via the endonuclease activity of the cleavage complex. Here, we detail the method to study cleavage reactions in vitro.

עיבוד פיין Loblolly PtGen2 cDNA microarray

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