עבודה זו נתמכה על ידי גילוי הילדים המכון מענק MC-II-2006-1 (RDM ו-TED), אפיגנטיקה NIH מפת הדרכים מענק [1R01DA025744-01 ו 3R01DA025744-02S1] (RDM ו FLMV), U01AG023746 (SC), Saigh קרן (FLMV ו-TED), 1K08CA140720-01A1 ולימונדה של אלכס תעמוד &quot;&quot; תמיכה פרס (TED). אנו מודים טכנולוגיה הגנום גישה מרכז במחלקה לגנטיקה באוניברסיטת וושינגטון בית הספר לרפואה עזרה עם ניתוח גנטי. המרכז נתמך חלקית NationalCenter לחקר משאבי (NCRR), מרכיב של המכונים הלאומיים לבריאות (NIH) על ידי NCI במרכז לחקר הסרטן תמיכה גרנט # p30 CA91842 למרכז הסרטן Siteman ועל ידי ICTS / CTSA גרנט # UL1RR024992, ו מפת הדרכים NIH למחקר רפואי. פרסום זה הינו באחריות הבלעדית של הכותבים ולא בהכרח מייצגים את העמדה הרשמית של NCRR או NIH.

<ol>
	<li>Vallania, F. L. M., Druley, T. E., Ramos, E., Wang, J., Borecki, I., Province, M., Mitra, R. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-throughput+discovery+of+rare+insertions+and+deletions+in+large+cohorts.">High-throughput discovery of rare insertions and deletions in large cohorts.</a> Genome Research. 20, 1391-1397 (2010).</li><li>Shendure, J., Mitra, R., Varma, C., Church, G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Advanced+Sequencing+Technologies:+Methods+and+Goals.">Advanced Sequencing Technologies: Methods and Goals.</a> Nature Reviews of Genetics. 5, 335-344 (2004).</li><li>The 1000 Genomes Project Consortium. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+map+of+human+genome+variation+from+population-scale+sequencing.">A map of human genome variation from population-scale sequencing.</a> Nature. 467, 1061-1073 (2010).</li><li>Manolio, T. A., Collins, F. S., Cox, N. J., Goldstein, D. B., Hindorff, L. A., Hunter, D. J., McCarthy, M. I., Ramos, E. M., Cardon, L. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Finding+the+missing+heritability+of+complex+diseases.">Finding the missing heritability of complex diseases.</a> Nature. 461, 747-753 (2009).</li><li>Reich, D. E., Lander, E. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+the+allelic+spectrum+of+human+disease.">On the allelic spectrum of human disease.</a> Trends Genet. 17, 502-510 (2001).</li><li>Cohen, J. C., Kiss, R. S., Pertsemlidis, A., Marcel, Y. L., McPherson, R., Hobbs, H. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multiple+rare+alleles+contribute+to+low+plasma+levels+of+HDL+cholesterol.">Multiple rare alleles contribute to low plasma levels of HDL cholesterol.</a> Science. 305, 869-872 (2004).</li><li>Ji, W., Foo, J. N., O'Roak, B. J., Zhao, H., Larson, M. G., Simon, D. B., Newton-Cheh, C., State, M. W., Levy, D., Lifton, R. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rare+independent+mutations+in+renal+salt+handling+genes+contribute+to+blood+pressure+variation.">Rare independent mutations in renal salt handling genes contribute to blood pressure variation.</a> Nat. Genet. 40, 592-599 (2008).</li><li>Ahituv, N., Kavaslar, N., Schackwitz, W., Ustaszewska, A., Martin, J., Hebert, S., Doelle, H., Ersoy, B., Kryukov, G., Schmidt, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Medical+sequencing+at+the+extremes+of+human+body+mass.">Medical sequencing at the extremes of human body mass.</a> Am. J. Hum. Genet. 80, 779-791 (2007).</li><li>Druley, T. E., Vallania, F. L., Wegner, D. J., Varley, K. E., Knowles, O. L., Bonds, J. A., Robison, S. W., Doniger, S. W., Hamvas, A., Cole, F. S., Fay, J. C., Mitra, R. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantification+of+rare+allelic+variants+from+pooled+genomic+DNA.">Quantification of rare allelic variants from pooled genomic DNA.</a> Nat. Methods. 6, 263-265 (2009).</li><li>Mitra, R. D., Butty, V., Shendure, J., Housman, D., Church, G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Digital+Genotyping+and+Haplotyping+with+Polymerase+Colonies.">Digital Genotyping and Haplotyping with Polymerase Colonies.</a> Proc. Natl. Acad. Sci. 100, 5926-5931 (2003).</li></ol>

אין ניגוד עניינים הצהיר.

ישנן ראיות כי הגדלת שכיחות תגובה טיפולית, של פנוטיפים נפוצים מורכבים ומחלות כגון 8 השמנת יתר, hypercholesterolemia 4, יתר לחץ דם 7 ואחרים ניתן בהנחיית פרופילים אישיים של וריאציה נדירה. זיהוי גנים ושבילים שם גרסאות אלה מצטברים באוכלוסיות שנפגעו יהיו השלכות האבחון והטיפול עמוקים, אבל ניתוח אנשים מושפעים בנפרד יכול להיות זמן ועלות אוסרני. האוכלוסייה המבוססת על ניתוח מציע שיטה יעילה יותר עבור מדידות שונות גנטית ב לוקוסים מרובים. אנו מציגים רומן ונקווה-DNA פרוטוקול רצף יחד עם חבילת Splinter תוכנה שנועדה לזהות סוג זה של שונות גנטית על פני אוכלוסיות. אנחנו מדגימים את רמת הדיוק של השיטה בזיהוי וכימות אללים קלים בקרב האוכלוסייה נקווה גדולה של 947 אנשים, כולל גרסאות נדירות שהיובשם דה נובו מן רצף נקווה ומאומתים על ידי pyrosequencing הפרט. האסטרטגיה שלנו שונה בעיקר פרוטוקולים אחרים על ידי שילוב של חיובי שליטה שלילית בתוך כל ניסוי. זה מאפשר Splinter להשיג דיוק גבוה הרבה יותר כוח לעומת גישות אחרות 1. כיסוי אופטימלי של פי 25 לכל אלל הוא קבוע ללא תלות בגודל של הבריכה, מה שהופך את הניתוח של בריכות גדולות ריאלי כמו דרישה זו רק קשקשים באופן ליניארי עם גודל הבריכה. הגישה שלנו היא גמישה מאוד יכול להיות מיושם על כל הפנוטיפ של עניין, אלא גם דגימות שהן הטרוגניות באופן טבעי, כגון אוכלוסיות תאים מעורבות ביופסיות הגידול. לאור ההתעניינות ההולכת וגוברת של רצף נקווה מאזורים יעד גדולים כמו exome או הגנום, הכנה הספרייה שלנו וניתוח Splinter תואם ללכוד מותאם אישית כולו exome רצף, אבל השירות יישור בחבילה Splinter לא תוכנן עבור גדולהפניות רצפים. לכן, אנו השתמשו בהצלחה aligner תכנות דינמי, Novoalign, על הגנום כולו מערכים ואחריו גרסה מתקשר מדגם נקווה (ראמוס et al. הגיש). לפיכך, האסטרטגיה שלנו ונקווה רצף יכול בהיקף בהצלחה לבריכות גדולות יותר עם כמויות הולכות וגדלות של רצף המטרה.

<table border="1" style=";text-align:right;direction:rtl"><tbody><tr><td> מגיב שם </td><td> חברה </td><td> מספר קטלוגי </td><td> סעיף </td></tr><tr><td> PfuUltra באיכות גבוהה </td><td> Agilent </td><td> 600384 </td><td> 1.4 </td></tr><tr><td> Betaine </td><td> SIGMA </td><td> B2629 </td><td> 1.4 </td></tr><tr><td> M13mp18 ssDNA וקטור </td><td> חוד </td><td> N4040S </td><td> 1.5 </td></tr><tr><td> pGEM-T קל </td><td> Promega </td><td> A1360 </td><td> 1.5 </td></tr><tr><td> Polynucleotide T4 קינאז </td><td> חוד </td><td> M0201S </td><td> 2.2 </td></tr><tr><td> האנזים T4 </td><td> חוד </td><td> M0202S </td><td> 2.2 </td></tr><tr><td> פוליאתילן גליקול 8000 MW </td><td> SIGMA </td><td> P5413 </td><td> 2.2 </td></tr><tr><td> Bioruptor sonicator </td><td> Diagenode </td><td> UCD-200-TS</td><td> 2.3 </td></tr></tbody></table>

detection of rare genomic variants from pooled sequencing using splinter

ככל שהטכנולוגיה רצפי DNA התקדמה במידה ניכרת בשנים האחרונות 2, זה הפך להיות ברור יותר ויותר כי כמות השונות הגנטית בין כל שני אנשים גדולה יותר מאשר סברו עד כה 3. לעומת זאת, מערך מבוסס genotyping לא הצליחה לזהות את התרומה המשמעותית של גרסאות רצף המשותפות השונות פנוטיפי של המחלה נפוצה 4,5. יחדיו, תצפיות אלה הובילו להתפתחות של מחלות נפוצות / ההשערה וריאנט נדיר המצביע על כך שרוב &quot;תורשתיות חסר&quot; של פנוטיפים נפוצים ומורכב הוא במקום בגלל הפרופיל האישי של הפרט גרסאות ה-DNA נדירים או פרטי 6-8 . עם זאת, המאפיין כמה וריאציה נדירה משפיע פנוטיפים מורכבים דורש ניתוח של אנשים מושפעים רבות על לוקוסים הגנומי רבים, והוא אידיאלי לעומת סקר דומה במדגם מעושה. למרות הכוח רצף המוצעים על ידי פלטפורמות של היום,האוכלוסייה המבוססת על סקר של לוקוסים הגנומי רבים ניתוח חישובית לאחר מכן נדרש עדיין מונע על חוקרים רבים. כדי לענות על צורך זה, פיתחנו גישה רצף נקווה 1,9 ואת חבילת תוכנה חדשה 1 לצורך זיהוי מדויק ביותר גרסה נדירה מן הנתונים המתקבלים. היכולת הגנום בריכת מאוכלוסיות שלמות של אנשים המושפעים ואת הסקר את מידת השונות הגנטית על אזורים ממוקדים מרובים בספריה רצף אחד מספק מצוינים חיסכון בעלויות וזמן המתודולוגיה מדגם יחיד המסורתית רצף. עם כיסוי רצף הממוצע לכל אלל של פי 25, האלגוריתם מותאם אישית שלנו, ספלינטר, משתמשת גרסה פנימי קורא השליטה אסטרטגיה לקרוא הוספות, מחיקות ותחליפים עד ארבעה זוגות בסיסים באורך עם רגישות וספציפיות גבוהה מבריכות של עד 1 אלל מוטנטי 500 אנשים. כאן אנו מתארים את השיטה להכנת s נקווהequencing ספריית ואחריו צעד אחר צעד הוראות כיצד להשתמש בחבילת Splinter לניתוח רצפי נקווה ( <a href="http://www.ibridgenetwork.org/wustl/splinter" target="_blank">http://www.ibridgenetwork.org/wustl/splinter</a> ). אנחנו מראים השוואה בין רצף משולב של 947 אנשים, כולם עברו גם הגנום כולו מערך, על פני רצף של 20kb לאדם. ההתאמה בין genotyping של מתויג גרסאות חדשות הנקראות במדגם נקווה היו מצוינים. שיטה זו וניתן לשנותם בקלות לכל מספר לוקוסים הגנומי וכל מספר של אנשים. על ידי שילוב של הבקרות הפנימיות amplicon חיוביות ושליליות על היחס המחקים את האוכלוסייה הנחקרת, האלגוריתם יכול להיות מכויל עבור ביצועים מיטביים. אסטרטגיה זו יכולה גם להיות שונה לשימוש עם לכידת ההכלאה או אדם ספציפיים ברקודים והוא יכול להיות מיושם על רצף של דגימות הטרוגניות באופן טבעי, כגון ה-DNA הגידול.

Watch this Scientific Journal Video about Detection of Rare Genomic Variants from Pooled Sequencing Using SPLINTER at JoVE.com

Detection of Rare Genomic Variants from Pooled Sequencing Using SPLINTER

רצפי DNA ונקווה היא אסטרטגיה מהיר וחסכוני לזהות גרסאות נדירים הקשורים פנוטיפים מורכבים של קבוצות גדולות. כאן אנו מתארים את ניתוח חישובי של רצפי נקווה הדור הבא, של 32 גנים הקשורים בסרטן באמצעות חבילת תוכנה ספלינטר. שיטה זו היא מדרגית, והיא חלה על כל הפנוטיפ של עניין.

זיהוי גנטי של וריאנטים נדירים מן הרצף נקווה שימוש Splinter

As DNA sequencing technology has markedly advanced in recent years2, it has become increasingly evident that the amount of genetic variation between any ...

detection-rare-genomic-variants-from-pooled-sequencing-using

Nanyang Technological University

Research

JoVE Journal

Biology

15.1K Views.  Washington University School of Medicine. רצפי DNA ונקווה היא אסטרטגיה מהיר וחסכוני לזהות גרסאות נדירים הקשורים פנוטיפים מורכבים של קבוצות גדולות. כאן אנו מתארים את ניתוח חישובי של רצפי נקווה הדור הבא, של 32 גנים הקשורים בסרטן באמצעות חבילת תוכנה ספלינטר. שיטה זו היא מדרגית, והיא חלה על כל הפנוטיפ של עניין....

Video: Detection of Rare Genomic Variants from Pooled Sequencing Using SPLINTER

Isolation of Genomic DNA from Mouse Tails

בידוד של הדנ&quot;א הגנומי של זנבות עכבר

Extraction of High Molecular Weight Genomic DNA from Soils and Sediments

The soil microbiome is a vast and relatively unexplored reservoir of genomic diversity and metabolic innovation that is intimately associated with nutrient and energy flow within terrestrial ecosystems. Cultivation-independent environmental genomic, also known as metagenomic, approaches promise unprecedented access to this genetic information with respect to pathway reconstruction and functional screening for high value therapeutic and biomass conversion processes. However, the soil microbiome still remains a challenge largely due to the difficulty in obtaining high molecular weight DNA of sufficient quality for large insert library production. Here we introduce a protocol for extracting high molecular weight, microbial community genomic DNA from soils and sediments. The quality of isolated genomic DNA is ideal for constructing large insert environmental genomic libraries for downstream sequencing and screening applications. 
The procedure starts with cell lysis. Cell walls and membranes of microbes are lysed by both mechanical (grinding) and chemical forces (&beta;-mercaptoethanol). Genomic DNA is then isolated using extraction buffer, chloroform-isoamyl alcohol and isopropyl alcohol. The buffers employed for the lysis and extraction steps include guanidine isothiocyanate and hexadecyltrimethylammonium bromide (CTAB) to preserve the integrity of the high molecular weight genomic DNA. Depending on your downstream application, the isolated genomic DNA can be further purified using cesium chloride (CsCl) gradient ultracentrifugation, which reduces impurities including humic acids. The first procedure, extraction, takes approximately 8 hours, excluding DNA quantification step. The CsCl gradient ultracentrifugation, is a two days process. During the entire procedure, genomic DNA should be treated gently to prevent shearing, avoid severe vortexing, and repetitive harsh pipetting.

A methodology to isolate high molecular weight and high quality genomic DNA from soil microbial community is described.

הפקת DNA גבוהה מולקולרית משקל הגנום מקרקעות ו משקעים

The soil microbiome is a vast and relatively unexplored reservoir of genomic diversity and metabolic innovation that is intimately associated with ...

Genomic MRI - a Public Resource for Studying Sequence Patterns within Genomic DNA

Non-coding genomic regions in complex eukaryotes, including intergenic areas, introns, and untranslated segments of exons, are profoundly non-random in their nucleotide composition and consist of a complex mosaic of sequence patterns. These patterns include so-called Mid-Range Inhomogeneity (MRI) regions -- sequences 30-10000 nucleotides in length that are enriched by a particular base or combination of bases (e.g. (G+T)-rich, purine-rich, etc.). MRI regions are associated with unusual (non-B-form) DNA structures that are often involved in regulation of gene expression, recombination, and other genetic processes (Fedorova &amp; Fedorov 2010). The existence of a strong fixation bias within MRI regions against mutations that tend to reduce their sequence inhomogeneity additionally supports the functionality and importance of these genomic sequences (Prakash et al. 2009).
Here we demonstrate a freely available Internet resource -- the Genomic MRI program package -- designed for computational analysis of genomic sequences in order to find and characterize various MRI patterns within them (Bechtel et al. 2008). This package also allows generation of randomized sequences with various properties and level of correspondence to the natural input DNA sequences. The main goal of this resource is to facilitate examination of vast regions of non-coding DNA that are still scarcely investigated and await thorough exploration and recognition.

We present a public computational web site for the analysis of genomic sequences. It detects DNA sequence patterns with various non-random nucleotide compositions. This resource also generates randomized sequences with diverse levels of complexity.

הגנום MRI - משאב ציבורי עבור לימוד דפוסי בתוך רצף הדנ&quot;א הגנומי

Non-coding genomic regions in complex eukaryotes, including intergenic areas, introns, and untranslated segments of exons, are profoundly non-random in ...

Competitive Genomic Screens of Barcoded Yeast Libraries

By virtue of advances in next generation sequencing technologies, we have access to new genome sequences almost daily. The tempo of these advances is accelerating, promising greater depth and breadth. In light of these extraordinary advances, the need for fast, parallel methods to define gene function becomes ever more important. Collections of genome-wide deletion mutants in yeasts and E. coli have served as workhorses for functional characterization of gene function, but this approach is not scalable, current gene-deletion approaches require each of the thousands of genes that comprise a genome to be deleted and verified. Only after this work is complete can we pursue high-throughput phenotyping. Over the past decade, our laboratory has refined a portfolio of competitive, miniaturized, high-throughput genome-wide assays that can be performed in parallel. This parallelization is possible because of the inclusion of DNA 'tags', or 'barcodes,' into each mutant, with the barcode serving as a proxy for the mutation and one can measure the barcode abundance to assess mutant fitness. In this study, we seek to fill the gap between DNA sequence and barcoded mutant collections. To accomplish this we introduce a combined transposon disruption-barcoding approach that opens up parallel barcode assays to newly sequenced, but poorly characterized microbes. To illustrate this approach we present a new Candida albicans barcoded disruption collection and describe how both microarray-based and next generation sequencing-based platforms can be used to collect 10,000 - 1,000,000 gene-gene and drug-gene interactions in a single experiment.

We have developed comprehensive, unbiased genome-wide screens to understand gene-drug and gene-environment interactions. Methods for screening these mutant collections are presented.

מסכי הגנום תחרותי של ספריות שמרים המבורקדים

By virtue of advances in next generation sequencing technologies, we have access to new genome sequences almost daily.  The tempo of these advances is ...

Studying Age-dependent Genomic Instability using the S. cerevisiae Chronological Lifespan Model

Studies using the Saccharomyces cerevisiae aging model have uncovered life span regulatory pathways that are partially conserved in higher eukaryotes1-2. The simplicity and power of the yeast aging model can also be explored to study DNA damage and genome maintenance as well as their contributions to diseases during aging. Here, we describe a system to study age-dependent DNA mutations, including base substitutions, frame-shift mutations, gross chromosomal rearrangements, and homologous/homeologous recombination, as well as nuclear DNA repair activity by combining the yeast chronological life span with simple DNA damage and mutation assays. The methods described here should facilitate the identification of genes/pathways that regulate genomic instability and the mechanisms that underlie age-dependent DNA mutations and cancer in mammals.

Studying Age-dependent Genomic Instability using the S. cerevisiae Chronological Lifespan Model

Here we describe a set of DNA mutation assays that can be combined with the yeast chronological life span model to study the genes/pathways that regulate or contribute to genomic DNA instability during aging.

לימוד גיל תלויי חוסר יציבות הגנום באמצעות ס cerevisiae דגם כרונולוגי תוחלת חיים

Studies using the Saccharomyces cerevisiae aging model have uncovered life span regulatory pathways that are partially conserved in higher eukaryotes1-2. ...

Selective Capture of 5-hydroxymethylcytosine from Genomic DNA

5-methylcytosine (5-mC) constitutes ~2-8% of the total cytosines in human genomic DNA and impacts a broad range of biological functions, including gene expression, maintenance of genome integrity, parental imprinting, X-chromosome inactivation, regulation of development, aging, and cancer1. Recently, the presence of an oxidized 5-mC, 5-hydroxymethylcytosine (5-hmC), was discovered in mammalian cells, in particular in embryonic stem (ES) cells and neuronal cells2-4. 5-hmC is generated by oxidation of 5-mC catalyzed by TET family iron (II)/&alpha;-ketoglutarate-dependent dioxygenases2, 3. 5-hmC is proposed to be involved in the maintenance of embryonic stem (mES) cell, normal hematopoiesis and malignancies, and zygote development2, 5-10. To better understand the function of 5-hmC, a reliable and straightforward sequencing system is essential. Traditional bisulfite sequencing cannot distinguish 5-hmC from 5-mC11. To unravel the biology of 5-hmC, we have developed a highly efficient and selective chemical approach to label and capture 5-hmC, taking advantage of a bacteriophage enzyme that adds a glucose moiety to 5-hmC specifically12.
Here we describe a straightforward two-step procedure for selective chemical labeling of 5-hmC. In the first labeling step, 5-hmC in genomic DNA is labeled with a 6-azide-glucose catalyzed by &beta;-GT, a glucosyltransferase from T4 bacteriophage, in a way that transfers the 6-azide-glucose to 5-hmC from the modified cofactor, UDP-6-N3-Glc (6-N3UDPG). In the second step, biotinylation, a disulfide biotin linker is attached to the azide group by click chemistry. Both steps are highly specific and efficient, leading to complete labeling regardless of the abundance of 5-hmC in genomic regions and giving extremely low background. Following biotinylation of 5-hmC, the 5-hmC-containing DNA fragments are then selectively captured using streptavidin beads in a density-independent manner. The resulting 5-hmC-enriched DNA fragments could be used for downstream analyses, including next-generation sequencing.
Our selective labeling and capture protocol confers high sensitivity, applicable to any source of genomic DNA with variable/diverse 5-hmC abundances. Although the main purpose of this protocol is its downstream application (i.e., next-generation sequencing to map out the 5-hmC distribution in genome), it is compatible with single-molecule, real-time SMRT (DNA) sequencing, which is capable of delivering single-base resolution sequencing of 5-hmC.

Described is a two-step labeling process using &beta;-glucosyltransferase (&beta;-GT) to transfer an azide-glucose to 5-hmC, followed by click chemistry to transfer a biotin linker for easy and density-independent enrichment. This efficient and specific labeling method enables enrichment of 5-hmC with extremely low background and high-throughput epigenomic mapping via next-generation sequencing.

לכידה סלקטיבית של 5-hydroxymethylcytosine מהדנ&quot;א הגנומי

5-methylcytosine (5-mC) constitutes ~2-8% of the total cytosines in human genomic DNA and impacts a broad range of biological functions, including gene ...

Array Comparative Genomic Hybridization (Array CGH) for Detection of Genomic Copy Number Variants

Array CGH for the detection of genomic copy number variants has replaced G-banded karyotype analysis. This paper describes the technology and its application in a clinical diagnostic service laboratory. DNA extracted from a patient&#8217;s sample (blood, saliva or other tissue types) is labeled with a fluorochrome (either cyanine 5 or cyanine 3). A reference DNA sample is labeled with the opposite fluorochrome. There follows a cleanup step to remove unincorporated nucleotides before the labeled DNAs are mixed and resuspended in a hybridization buffer and applied to an array comprising ~60,000 oligonucleotide probes from loci across the genome, with high probe density in clinically important areas. Following hybridization, the arrays are washed, then scanned and the resulting images are analyzed to measure the red and green fluorescence for each probe. Software is used to assess the quality of each probe measurement, calculate the ratio of red to green fluorescence and detect potential copy number variants.

Array Comparative Genomic Hybridization Array CGH for Detection of Genomic Copy Number Variants

Array CGH for the detection of genomic copy number variants has replaced G-banded karyotype analysis. This paper describes the technology and its application in a diagnostic service laboratory.

מערך השוואתי הגנום הכלאה (Array CGH) לאיתור של הגנום גרסאות מספר עותק

Array CGH for the detection of genomic copy number variants has replaced G-banded karyotype analysis. This paper describes the technology and its ...

Isolating Potentiated Hsp104 Variants Using Yeast Proteinopathy Models

Many protein-misfolding disorders can be modeled in the budding yeast Saccharomyces cerevisiae. Proteins such as TDP-43 and FUS, implicated in amyotrophic lateral sclerosis, and &#945;-synuclein, implicated in Parkinson&#8217;s disease, are toxic and form cytoplasmic aggregates in yeast. These features recapitulate protein pathologies observed in patients with these disorders. Thus, yeast are an ideal platform for isolating toxicity suppressors from libraries of protein variants. We are interested in applying protein disaggregases to eliminate misfolded toxic protein conformers. Specifically, we are engineering Hsp104, a hexameric AAA+ protein from yeast that is uniquely capable of solubilizing both disordered aggregates and amyloid and returning the proteins to their native conformations. While Hsp104 is highly conserved in eukaryotes and eubacteria, it has no known metazoan homologue. Hsp104 has only limited ability to eliminate disordered aggregates and amyloid fibers implicated in human disease. Thus, we aim to engineer Hsp104 variants to reverse the protein misfolding implicated in neurodegenerative disorders. We have developed methods to screen large libraries of Hsp104 variants for suppression of proteotoxicity in yeast. As yeast are prone to spontaneous nonspecific suppression of toxicity, a two-step screening process has been developed to eliminate false positives. Using these methods, we have identified a series of potentiated Hsp104 variants that potently suppress the toxicity and aggregation of TDP-43, FUS, and &#945;-synuclein. Here, we describe this optimized protocol, which could be adapted to screen libraries constructed using any protein backbone for suppression of toxicity of any protein that is toxic in yeast.

Yeast proteinopathy models are valuable tools to assess the toxicity and aggregation of proteins implicated in disease. Here, we present methods for screening Hsp104 variant libraries for toxicity suppressors. This protocol could be adapted to screen any protein library for toxicity suppressors of any protein that is toxic in yeast.

בידוד דוגמניות Proteinopathy שמרי שימוש potentiated Hsp104 גרסאות

Many protein-misfolding disorders can be modeled in the budding yeast Saccharomyces cerevisiae. Proteins such as TDP-43 and FUS, implicated in amyotrophic ...

Evaluation of Zebrafish Kidney Function Using a Fluorescent Clearance Assay

The zebrafish embryo offers a tractable model to study organogenesis and model human genetic disease. Despite its relative simplicity, the zebrafish kidney develops and functions in almost the same way as humans. A major difference in the construction of the human kidney is the presence of millions of nephrons compared to the zebrafish that has only two. However, simplifying such a complex system into basic functional units has aided our understanding of how the kidney develops and operates. In zebrafish, the midline located glomerulus is responsible for the initial blood filtration into two pronephric tubules that diverge to run bilaterally down the embryonic axis before fusing to each other at the cloaca. The pronephric tubules are heavily populated by motile cilia that facilitate the movement of filtrate along the segmented tubule, allowing the exchange of various solutes before finally exiting via the cloaca2-4. Many genes responsible for CKD, including those related to ciliogenesis, have been studied in zebrafish5. However, a major draw back has been the difficulty in evaluating zebrafish kidney function after genetic manipulation. Traditional assays to measure kidney dysfunction in humans have proved non translational to zebrafish, mainly due to their aquatic environment and small size. For example, it is not physically possible to extract blood from embryonic staged fish for analysis of urea and creatinine content, as they are too small. In addition, zebrafish do not produce enough urine for testing on a simple proteinuria &#8216;dipstick&#8217;, which is often performed during initial patient examinations. We describe a fluorescent assay that utilizes the optical transparency of the zebrafish to quantitatively monitor the clearance of a fluorescent dye, over time, from the vasculature and out through the kidney, to give a read out of renal function1,6-9.

The zebrafish is a popular tool to model chronic kidney disease (CKD). However, their small size makes it impossible to evaluate renal function using traditional methods. We describe a fluorescent dye kidney clearance assay1 that allows quantitative analysis of zebrafish kidney function in CKD.

הערכה של תפקוד כליה דג הזברה באמצעות assay עמילות פלורסנט

The zebrafish embryo offers a tractable model to study organogenesis and model human genetic disease. Despite its relative simplicity, the zebrafish ...

TRAP-rc, Translating Ribosome Affinity Purification from Rare Cell Populations of Drosophila Embryos

Measuring levels of mRNAs in the process of translation in individual cells provides information on the proteins involved in cellular functions at a given point in time. The protocol dubbed Translating Ribosome Affinity Purification (TRAP) is able to capture this mRNA translation process in a cell-type-specific manner. Based on the affinity purification of polysomes carrying a tagged ribosomal subunit, TRAP can be applied to translatome analyses in individual cells, making it possible to compare cell types during the course of developmental processes or to track disease development progress and the impact of potential therapies at molecular level. Here we report an optimized version of the TRAP protocol, called TRAP-rc (rare cells), dedicated to identifying engaged-in-translation RNAs from rare cell populations. TRAP-rc was validated using the Gal4/UAS targeting system in a restricted population of muscle cells in Drosophila embryos. This novel protocol allows the recovery of cell-type-specific RNA in sufficient quantities for global gene expression analytics such as microarrays or RNA-seq. The robustness of the protocol and the large collections of Gal4 drivers make TRAP-rc a highly versatile approach with potential applications in cell-specific genome-wide studies.

TRAP-rc, Translating Ribosome Affinity Purification from Rare Cell Populations of Drosophila Embryos

Translating Ribosome Affinity Purification (TRAP) is able to capture cell-type-specific translation of mRNA. Here we report the first TRAP protocol dedicated to isolation of mRNA in rare cell populations of Drosophila embryos.

מלכודת RC, תרגום ריבוזום זיקה טיהור מאוכלוסיות תאים נדירות של<em&gt; דרוזופילה</em&gt; עוברים

Measuring levels of mRNAs in the process of translation in individual cells provides information on the proteins involved in cellular functions at a given ...