Name: technical demonstration of whole genome array comparative genomic hybridization
Uploaded: 2008-08-05T18:06:00.000+00:00
Duration: 16 min 37 s
Description: Watch this Scientific Journal Video about Technical Demonstration of Whole Genome Array Comparative Genomic Hybridization at JoVE.com

我们要感谢为编写本文运临实验室的BAC阵列队，特别是三轮铃木和布赖恩志的成员。这项工作是支持由来自加拿大研究所的资金卫生研究院，加拿大基因组/基因组不列颠哥伦比亚省和美国国立卫生研究院/ NIDCR授予RO1 DE15965 - 01。

探针标记 注：限制接触CYE染料在任何时候都光（这可以通过在黑暗的领域工作，或屏蔽如铝箔盖管） <ol><li>结合： （安装1个反应管样品，以供参考和1个反应管） <ul><li> DNA（25-400纳克） </li><li> 5μL5X缓冲随机引物（终浓度：5X Promega公司的Klenow缓冲和7微克/μL，随机八聚体） </li><li>稀释到17.0μL，用蒸馏水H 2 O的总体积</li></ul></li><li>煮沸10分钟，在100 ° C。立即转移到1分钟的冰。 </li><li>加入4μL10X dNTP混合液（2MM的dATP，dGTP，dTTP的，1.2mm的dCTP）。 </li><li>新增CyeDyes： <ul><li> CY - 3标记的dCTP 2μL（2 nmoles）样品DNA </li><li> CY - 5标记的dCTP 2μL（2 nmoles）参考DNA（例如，Novagen公司人类基因组DNA） </li></ul></li><li>添加2.5μL的Klenow（9 U /μL，Promega公司）和混合。 </li><li>在37 ° C孵育过夜*（〜18小时）。 *杂交过夜时间可以调整14至24小时之间，无不良影响贴标过程，以适应实验室时间表。 </li></ol>样本数据库 （探头的清理和准备杂交组合） <ol><li>使用一个单片机YM - 30柱： <ul><li>添加100μLCOT - 1 DNA（1μg/μL）列。请勿触摸膜与枪头。 </li><li>游泳池的反应（参考样本），并添加到列。 </li><li>将列在提供管和旋转10分钟，在13000克。 </li><li>加入200微升蒸馏水2 0膜和重复旋转洗。 </li><li>丢弃管，添加45μL杂交液：（罗氏辛易） </li></ul>可选：添加5μL剪切鲱鱼精子DNA（10μg/μL单位，Promega公司） <ul><li>反转单片机，在一个新的标记管的地方，并在3000克3分钟旋转。 </li></ul></li></ol>的法团的计算<ol><li>卸下1.5μL和使用NanoDrop分光光度计测量荧光法团。使用您的杂交缓冲液作为空白（辛轻松）按照屏幕上的指示。 （您可以从底座中恢复过来的样品，测量后，如果必要的。） （ 注：低于3.0 pmol /μL在任一通道的法团有不同的结果。 ） </li><li>变性在85 ° C 10分钟。 </li><li>将探头放置在45 ° C 30分钟至1小时（允许COT - 1 DNA退火。） </li></ol>阵列杂交<ol><li>广场44μL到盖玻片探头解决方案（22毫米× 60毫米）（尔科技）。如果可以，盖玻片放在幻灯片温暖或热块预热至45 ° C，保持温度。 </li><li>对齐滑动盖玻片和探头解决方案，低的一个幻灯片的边缘，使杂交液接触。继续降低，直到盖玻片表面张力的幻灯片。反向滑动。 </li><li>放置到杂交带（Telechem）的幻灯片，预热至45 ° C，并添加10μL的水，在低槽（控制杂交过程中的湿度）。 </li><li>密封的纸盒和孵育36 - 40小时在45 ° C。 </li></ol>阵列洗涤 注：所有的清洗解决方案，在pH 7.0 从杂交盒去除幻灯片是至关重要的。辛轻松快速晶体在室温下。幻灯片，应立即浸入和盖玻片，在洗涤液中删除。 <ol><li>加入约60毫升0.1XSSC，0.1％SDS（pH值7.0，45℃）洗一个Coplin JAR的解决方案之前，开放的杂交室。 </li><li>开放室，添加幻灯片洗涤液，取出盖玻片（应滑出）。 </li><li>洗净幻灯片0.1XSSC 3倍+ 0.1％SDS在45℃，各1分钟与躁动。 </li><li>冲洗幻灯片新鲜0.1XSSC的3倍*。应无残留的气泡从SDS洗可见。 *幻灯片可以保持在最后的洗涤液，直到准备离心机和扫描（〜15分钟）。 </li><li>离心3分钟，在700克50毫升猎鹰管的幻灯片。 </li><li>立即扫描幻灯片（信号强度会随着时间的推移减弱。） </li></ol>

<ol>
	<li>Lockwood, W. W., Chari, R., Chi, B., Lam, W. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+advances+in+array+comparative+genomic+hybridization+technologies+and+their+applications+in+human+genetics.">Recent advances in array comparative genomic hybridization technologies and their applications in human genetics.</a> European Journal of Human Genetics. 14, 139-1x`48 (2006).</li><li>Ishkanian, A. S., Malloff, C. A., Watson, S. K., deLeeuw, R. J., Chi, B., Coe, B. P., Snijders, A., Albertson, D. G., Pinkel, D., Marra, M. A., Ling, V., MacAulay, C., Lam, W. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+tiling+resolution+DNA+microarray+with+complete+coverage+of+the+human+genome.">A tiling resolution DNA microarray with complete coverage of the human genome.</a> Nature Genetics. 36, 299-303 (2004).</li><li>Watson, S. K., DeLeeuw, R. J., Ishkanian, A. S., Malloff, C. A., Lam, W. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Methods+for+high+throughput+validation+of+amplified+fragment+pools+of+BAC+DNA+for+constructing+high+resolution+CGH+arrays.">Methods for high throughput validation of amplified fragment pools of BAC DNA for constructing high resolution CGH arrays.</a> BMC Genomics. 5, 6 (2004).</li><li>Watson, S. K., DeLeeuw, R. J., Horsman, D. E., Squire, J. A., Lam, W. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cytogenetically+balanced+translocations+are+associated+with+focal+copy+number+alterations.">Cytogenetically balanced translocations are associated with focal copy number alterations.</a> Human Genetics. 120, 795-805 (2007).</li><li>Chi, B., DeLeeuw, R. J., Coe, B. P., MacAulay, C., Lam, W. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=SeeGH+--+a+software+tool+for+visualization+of+whole+genome+array+comparative+genomic+hybridization+data.">SeeGH -- a software tool for visualization of whole genome array comparative genomic hybridization data.</a> BMC Bioinformatics. 5, 13 (2004).</li><li>Chi, B., DeLeeuw, R. J., Coe, B. P., Ng, R. T., MacAulay, C., Lam, W. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MD-SeeGH:+a+platform+for+integrative+analysis+of+multi-dimensional+genomic+data.">MD-SeeGH: a platform for integrative analysis of multi-dimensional genomic data.</a> BMC Bioinformatics. 9, 243 (2008).</li><li>Coe, B. P., Ylstra, B., Carvalho, B., Meijer, G. A., Macaulay, C., Lam, W. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Resolving+the+resolution+of+array+CGH.">Resolving the resolution of array CGH.</a> Genomics. 89, 647-653 (2007).</li><li>Garnis, C., Coe, B. P., Lam, S. L., MacAulay, C., Lam, W. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-resolution+array+CGH+increases+heterogeneity+tolerance+in+the+analysis+of+clinical+samples.">High-resolution array CGH increases heterogeneity tolerance in the analysis of clinical samples.</a> Genomics. 85, 790-793 (2005).</li></ol>

质量差的DNA，将不会提供一个良好的杂交个人资料。它是必不可少的，以确保样品和参照DNA污染物，如苯酚，RNA，盐等可能与干预的随机总理标签步骤之前开始杂交实验。例如再悬浮的DNA在Tris - EDTA代替水（TE）是不建议高盐浓度能抑制标记反应。我们建议使用Nanodrop分光光度计测量DNA的数量以及吸光度曲线的整体形状和260/280，二百三十分之二百六十零比例化验DNA的质量。 洗衣机：从杂交盒中删除的幻灯片?...

<table><tbody><tr><td>5X Klenow Buffer</td><td>Reagent</td><td>Promega Corp.</td><td></td><td></td></tr><tr><td>Random Octamers </td><td>Reagent</td><td>Alpha DNA</td><td></td><td></td></tr><tr><td>10X dNTP mix</td><td>Reagent</td><td>Promega Corp.</td><td></td><td>2mM dATP, dGTP, dTTP, 1.2mM dCTP</td></tr><tr><td>Cy-3 labeled dCTP</td><td>Reagent</td><td>GE Healthcare</td><td></td><td></td></tr><tr><td>Cy-5 labeled dCTP</td><td>Reagent</td><td>GE Healthcare</td><td></td><td></td></tr><tr><td>Human Genomic DNA Reference</td><td>Reagent</td><td>Novagen, EMD Millipore</td><td></td><td>Example of a possible reference</td></tr><tr><td>Klenow</td><td>Reagent</td><td>Promega Corp.</td><td></td><td></td></tr><tr><td>YM-30 Column</td><td>Reagent</td><td>EMD Millipore</td><td></td><td></td></tr><tr><td>Cot-1 DNA</td><td>Reagent</td><td>Invitrogen</td><td></td><td></td></tr><tr><td>DIG Easy</td><td>Reagent</td><td>Roche Group</td><td></td><td></td></tr><tr><td>Sheared Herring Sperm DNA</td><td>Reagent</td><td>Promega Corp.</td><td></td><td></td></tr><tr><td>Coverslip</td><td>Reagent</td><td>Fisher Scientific</td><td></td><td>22mm x 60mm</td></tr><tr><td>Hybridization Cassette</td><td>Tool</td><td>Telechem</td><td></td><td></td></tr></tbody></table>

technical demonstration of whole genome array comparative genomic hybridization

阵列比较基因组杂交（阵列CGH）技术是一种检测DNA片段或基因的基因组中的1剂量的收益和损失的方法。这项技术的最新进展，使高分辨率的整个基因组的遗传变异在癌症和其他遗传性疾病 2鉴定比较。小组Megabase分辨率平铺设置阵列（SMRT）阵列是由一组细菌人工染色体（BAC），跨越2〜100个碱基对的人类基因组（KB）段的克隆约三万重叠。这些BAC的目标是独立的合成和发现重复单一载玻片 2-4 。阵列比较基因组杂交的基础上有竞争力的杂交的原则。样品和参照DNA差异与菁- 3标记和荧光染料菁- 5，和合作的阵列杂交。潜伏期后，未​​结合的样品从幻灯片冲洗成像阵列。 SeeGH（www.flintbox.ca）免费提供的自定义软件包是用来处理大量的数据收集 - 一个单一的实验产生53892个数据点。 SeeGH可视化之间在每个BAC目标的2样品与5,6染色体的位置，这是垂直对齐的log2信号强度的比值。 SMRT的阵列，可以检测高达50 KB的大小 7小的改动。 SMRT的阵列，可以检测多种，包括DNA的收益，损失，扩增和纯合性缺失的DNA重组事件。 SMRT的阵列的一个独特优势是，可以使用从福尔马林固定石蜡包埋样品中分离DNA。当与非放大的DNA（25 - 100ng）的低投入的要求相结合 ，这使得如7,8显微切割生产的珍贵样品的分析。这要归功于大尺寸每个BAC杂交的目标，让约束力，以生产足够的标记的样品进行检测的信号。这个平台的另一个优势是组织异质性的耐受性，减少繁琐的组织显微切割8的需要。此视频的协议是一个标签输入DNA，通过对整个基因组的瓦片路径SMRT的阵列信号收购一步一步的教程。

Watch this Scientific Journal Video about Technical Demonstration of Whole Genome Array Comparative Genomic Hybridization at JoVE.com

Technical Demonstration of Whole Genome Array Comparative Genomic Hybridization

这个视频是一个全基因组平铺路径阵列比较基因组杂交，扫描整个人类基因组只用25-100纳克的DNA，可以从多种来源，包括档案福尔马林固定材料隔离​​技术示范的杂交协议。

全基因组阵列比较基因组杂交技术示范

Array comparative genomic hybridization (array CGH) is a method for detecting gains and losses of DNA segments or gene dosage in the genome 1.  Recent ...

technical-demonstration-whole-genome-array-comparative-genomic

Research

JoVE Journal

Biology

12.7K 次观看.  BC Cancer Research Centre. *The slides can remain in the 

视频: Technical Demonstration of Whole Genome Array Comparative Genomic Hybridization

The Terroir Concept Interpreted through Grape Berry Metabolomics and Transcriptomics

Terroir refers to the combination of environmental factors that affect the characteristics of crops such as grapevine (Vitis vinifera) according to particular habitats and management practices. This article shows how certain terroir signatures can be detected in the berry metabolome and transcriptome of the grapevine cultivar Corvina using multivariate statistical analysis. The method first requires an appropriate sampling plan. In this case study, a specific clone of the Corvina cultivar was selected to minimize genetic differences, and samples were collected from seven vineyards representing three different macro-zones during three different growing seasons. An untargeted LC-MS metabolomics approach is recommended due to its high sensitivity, accompanied by efficient data processing using MZmine software and a metabolite identification strategy based on fragmentation tree analysis. Comprehensive transcriptome analysis can be achieved using microarrays containing probes covering ~99% of all predicted grapevine genes, allowing the simultaneous analysis of all differentially expressed genes in the context of different terroirs. Finally, multivariate data analysis based on projection methods can be used to overcome the strong vintage-specific effect, allowing the metabolomics and transcriptomics data to be integrated and analyzed in detail to identify informative correlations.

This article describes the application of untargeted metabolomics, transcriptomics and multivariate statistical analysis to grape berry transcripts and metabolites in order to gain insight into the terroir concept, i.e., the impact of the environment on berry quality traits.

风土通过概念葡萄果实代谢组学和转录组解释的

Terroir refers to the combination of environmental factors that affect the characteristics of crops such as grapevine (Vitis vinifera) according to ...

科研

遗传学

An Array-based Comparative Genomic Hybridization Platform for Efficient Detection of Copy Number Variations in Fast Neutron-induced Medicago truncatula Mutants

Mutants are invaluable genetic resources for gene function studies. To generate mutant collections, three types of mutagens can be utilized, including biological such as T-DNA or transposon, chemical such as ethyl methanesulfonate (EMS), or physical such as ionization radiation. The type of mutation observed varies depending on the mutagen used. For ionization radiation induced mutants, mutations include deletion, duplication, or rearrangement. While T-DNA or transposon-based mutagenesis is limited to species that are susceptible to transformation, chemical or physical mutagenesis can be applied to a broad range of species. However, the characterization of mutations derived from chemical or physical mutagenesis traditionally relies on a map-based cloning approach, which is labor intensive and time consuming. Here, we show that a high-density genome array-based comparative genomic hybridization (aCGH) platform can be applied to efficiently detect and characterize copy number variations (CNVs) in mutants derived from fast neutron bombardment (FNB) mutagenesis in Medicago truncatula, a legume species. Whole genome sequence analysis shows that there are more than 50,000 genes or gene models in M. truncatula. At present, FNB-induced mutants in M. truncatula are derived from more than 150,000 M1 lines, representing invaluable genetic resources for functional studies of genes in the genome. The aCGH platform described here is an efficient tool for characterizing FNB-induced mutants in M. truncatula.

An Array-based Comparative Genomic Hybridization Platform for Efficient Detection of Copy Number Variations in Fast Neutron-induced Medicago truncatula Mutants

This protocol provides experimental steps and information about reagents, equipment, and analysis tools for researchers who are interested in carrying out whole genome array-based comparative genomic hybridization (CGH) analysis of copy number variations in plants.

一种基于阵列的比较基因组杂交平台, 有效检测快中子诱导的苜蓿蒺藜突变体的拷贝数变化

Mutants are invaluable genetic resources for gene function studies. To generate mutant collections, three types of mutagens can be utilized, including ...

High-Density DNA and RNA microarrays - Photolithographic Synthesis, Hybridization and Preparation of Large Nucleic Acid Libraries

Photolithography is a powerful technique for the synthesis of DNA oligonucleotides on glass slides, as it combines the efficiency of phosphoramidite coupling reactions with the precision and density of UV light reflected from micrometer-sized mirrors. Photolithography yields microarrays that can accommodate from hundreds of thousands up to several million different DNA sequences, 100-nt or longer, in only a few hours. With this very large sequence space, microarrays are ideal platforms for exploring the mechanisms of nucleic acid&#183;ligand interactions, which are particularly relevant in the case of RNA. We recently reported on the preparation of a new set of RNA phosphoramidites compatible with in situ photolithography and which were subsequently used to grow RNA oligonucleotides, homopolymers as well as mixed-base sequences. Here, we illustrate in detail the process of RNA microarray fabrication, from the experimental design, to instrumental setup, array synthesis, deprotection and final hybridization assay using a template 25mer sequence containing all four bases as an example. In parallel, we go beyond hybridization-based experiments and exploit microarray photolithography as an inexpensive gateway to complex nucleic acid libraries. To do so, high-density DNA microarrays are fabricated on a base-sensitive monomer that allows the DNA to be conveniently cleaved and retrieved after synthesis and deprotection. The fabrication protocol is optimized so as to limit the number of synthetic errors and to that effect, a layer of &#946;-carotene solution is introduced to absorb UV photons that may otherwise reflect back onto the synthesis substrates. We describe in a step-by-step manner the complete process of library preparation, from design to cleavage and quantification.

In this article, we present and discuss new developments in the synthesis and applications of nucleic acid microarrays fabricated in situ. Specifically, we show how the protocols for DNA synthesis can be extended to RNA and how microarrays can be used to create retrievable nucleic acid libraries.

高密度DNA和RNA微阵列.光刻合成、杂交和制备大型核酸库

Photolithography is a powerful technique for the synthesis of DNA oligonucleotides on glass slides, as it combines the efficiency of phosphoramidite ...

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.

全球基因表达分析，使用斑马鱼的寡核苷酸芯片平台

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

生物学

A Rapid High-throughput Method for Mapping Ribonucleoproteins (RNPs) on Human pre-mRNA

Sequencing RNAs that co-immunoprecipitate (co-IP) with RNA binding proteins has increased our understanding of splicing by demonstrating that binding location often influences function of a splicing factor.  However, as with any sampling strategy the chance of identifying an RNA bound to a splicing factor is proportional to its cellular abundance.  We have developed a novel in vitro approach for surveying binding specificity on otherwise transient pre-mRNA. This approach utilizes a specifically designed oligonucleotide pool that tiles across introns, exons, splice junctions, or other pre-mRNA.  The pool is subjected to some kind of molecular selection. Here, we demonstrate the method by separating the oligonucleotide into a bound and unbound fraction and utilize a two color array strategy to record the enrichment of each oligonucleotide in the bound fraction. The array data generates high-resolution maps with the ability to identify sequence-specific and structural determinates of ribonucleoprotein (RNP) binding on pre-mRNA.  A unique advantage to this method is its ability to avoid the sampling bias towards mRNA associated with current IP and SELEX techniques, as the pool is specifically designed and synthesized from pre-mRNA sequence. The flexibility of the oligonucleotide pool is another advantage since the experimenter chooses which regions to study and tile across, tailoring the pool to their individual needs.  Using this technique, one can assay the effects of polymorphisms or mutations on binding on a large scale or clone the library into a functional splicing reporter and identify oligonucleotides that are enriched in the included fraction.  This novel in vitro high-resolution mapping scheme provides a unique way to study RNP interactions with transient pre-mRNA species, whose low abundance makes them difficult to study with current in vivo techniques.  



A Rapid High-throughput Method for Mapping Ribonucleoproteins RNPs on Human pre-mRNA

Due to the transient nature of pre-mRNA, it can be difficult to isolate and study in vivo. Here, we present a novel in vitro approach to investigate RNA-protein interactions using a synthetic oligo pool that tiles across selected regions of pre-mRNA.

一种快速高通量的方法映射核糖核蛋白（RNPs）人类的前体mRNA

Sequencing RNAs that co-immunoprecipitate (co-IP) with RNA binding proteins has increased our understanding of splicing by demonstrating that binding ...

A Novel Strategy Combining Array-CGH, Whole-exome Sequencing and In Utero Electroporation in Rodents to Identify Causative Genes for Brain Malformations

Birth defects that involve the cerebral cortex &#8212; also known as malformations of cortical development (MCD) &#8212; are important causes of intellectual disability and account for 20-40% of drug-resistant epilepsy in childhood. High-resolution brain imaging has facilitated in vivo identification of a large group of MCD phenotypes. Despite the advances in brain imaging, genomic analysis and generation of animal models, a straightforward workflow to systematically prioritize candidate genes and to test functional effects of putative mutations is missing. To overcome this problem, an experimental strategy enabling the identification of novel causative genes for MCD was developed and validated. This strategy is based on identifying candidate genomic regions or genes via array-CGH or whole-exome sequencing and characterizing the effects of their inactivation or of overexpression of specific mutations in developing rodent brains via in utero electroporation. This approach led to the identification of the C6orf70 gene, encoding for a putative vesicular protein, to the pathogenesis of periventricular nodular heterotopia, a MCD caused by defective neuronal migration.

A Novel Strategy Combining Array-CGH, Whole-exome Sequencing and In Utero Electroporation in Rodents to Identify Causative Genes for Brain Malformations

Periventricular nodular heterotopia (PNH) is the most common form of malformation of cortical development (MCD) in adulthood but its genetic basis remains unknown in most sporadic cases. We have recently developed a strategy to identify novel candidate genes for MCDs and to directly confirm their causative role in vivo.

一种新的结合阵列全息、全外测序和宫内电穿孔的方法来识别脑畸形的致病基因

Birth defects that involve the cerebral cortex &#8212; also known as malformations of cortical development (MCD) &#8212; are important causes of ...

神经科学

DNA Microarrays: Sample Quality Control, Array Hybridization and Scanning

Microarray expression profiling of the nervous system provides a powerful approach to identifying gene activities in different stages of development, different physiological or pathological states, response to therapy, and, in general, any condition that is being experimentally tested1. Expression profiling of neural tissues requires isolation of high quality RNA, amplification of the isolated RNA and hybridization to DNA microarrays. In this article we describe protocols for reproducible microarray experiments from brain tumor tissue2. We will start by performing a quality control analysis of isolated RNA samples with Agilent's 2100 Bioanalyzer "lab-on-a-chip" technology. High quality RNA samples are critical for the success of any microarray experiment, and the 2100 Bioanalyzer provides a quick, quantitative measurement of the sample quality. RNA samples are then amplified and labeled by performing reverse transcription to obtain cDNA, followed by in vitro transcription in the presence of labeled nucleotides to produce labeled cRNA. By using a dual-color labeling kit, we will label our experimental sample with Cy3 and a reference sample with Cy5. Both samples will then be combined and hybridized to Agilent's 4x44 K arrays. Dual-color arrays offer the advantage of a direct comparison between two RNA samples, thereby increasing the accuracy of the measurements, in particular for small changes in expression levels, because the two RNA samples are hybridized competitively to a single microarray. The arrays will be scanned at the two corresponding wavelengths, and the ratio of Cy3 to Cy5 signal for each feature will be used as a direct measurement of the relative abundance of the corresponding mRNA. This analysis identifies genes that are differentially expressed in response to the experimental conditions being tested.

We demonstrate the use of DNA microarrays for expression profiling of the nervous system. We describe RNA quality control, sample labeling, and array hybridization and scanning.

DNA微阵列：样品的质量控制，阵列杂交和扫描

Microarray expression profiling of the nervous system provides a powerful approach to identifying gene activities in different stages of development, ...

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.

条形码酵母图书馆竞争力的基因屏幕

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

DNA-affinity-purified Chip (DAP-chip) Method to Determine Gene Targets for Bacterial Two component Regulatory Systems

In vivo methods such as ChIP-chip are well-established techniques used to determine global gene targets for transcription factors. However, they are of limited use in exploring bacterial two component regulatory systems with uncharacterized activation conditions. Such systems regulate transcription only when activated in the presence of unique signals. Since these signals are often unknown, the in vitro microarray based method described in this video article can be used to determine gene targets and binding sites for response regulators. This DNA-affinity-purified-chip method may be used for any purified regulator in any organism with a sequenced genome. The protocol involves allowing the purified tagged protein to bind to sheared genomic DNA and then affinity purifying the protein-bound DNA, followed by fluorescent labeling of the DNA and hybridization to a custom tiling array. Preceding steps that may be used to optimize the assay for specific regulators are also described. The peaks generated by the array data analysis are used to predict binding site motifs, which are then experimentally validated. The motif predictions can be further used to determine gene targets of orthologous response regulators in closely related species. We demonstrate the applicability of this method by determining the gene targets and binding site motifs and thus predicting the function for a sigma54-dependent response regulator DVU3023 in the environmental bacterium Desulfovibrio vulgaris Hildenborough.

DNA-affinity-purified Chip DAP-chip Method to Determine Gene Targets for Bacterial Two component Regulatory Systems

This video article describes an in vitro microarray based method to determine the gene targets and binding sites for two component system response regulators.

DNA的亲和纯化的芯片（DAP芯片）方法来确定目标基因的细菌双组分调控系统

In vivo methods such as ChIP-chip are well-established techniques used to determine global gene targets for transcription factors. However, they are of ...

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.