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Sample GSM418600 Query DataSets for GSM418600
Status Public on Jun 24, 2009
Title L3_8wg16_3_of_3_rep_2
Sample type genomic
 
Channel 1
Source name L3_8wg16
Organism Drosophila melanogaster
Characteristics antibody: PolII (8wg16)
antibody manufacturer: Covance
antibody catalog number: MMS-126R
antibody lot number: 14861301
test: ChIP
Treatment protocol No treatment
Growth protocol 1. y; bw cn sp flies are cultivated in cages with apple juice agar plates covered with yeast powder. 2. For a collection of third instar larvae (L3), new plates are added after a 2 hours pre-egglaying at 9 am and flies are allowed to lay eggs for 24 hours. Plates are then kept at 25C for another 48 hours. 3. L3 larvae are collected at 8.45 am using a filter mesh and a brush. L3 larvae are the larvae not going through the first mesh. They are rinsed with EWB and cross-linked at 9 am in 1.8% formaldehyde at room temperature for 15 min.
Extracted molecule genomic DNA
Extraction protocol Drosophila samples are crushed in presence of 1.8% of formaldehyde for 15 minutes. After washing, the material is sonicated for 15 minutes to solubilize the chromatin. After centrifugation, the supernatant containing soluble chromatin is collected for IPs. Specific antibodies are added to the chromatin extract while one aliquot will be treated for DNA extraction corresponding to the reference samples. ChIP are carried overnight at room temperature. Protein A Sepharose beads are used to pull down the chromatin bound antibodies. After washes and finally elution, the DNA corresponding to the IP'd material is extracted and purified. Amplification of the DNA is done by linker-mediated PCR and used for labeling.
Label Cy3
Label protocol 2 ug of amplified IP DNA are used for random primer labeling reaction (invitrogen). Cy3-dCTP is incorporated for the ChIP samples while Cy5-dCTP is incorporated for the Input chromatin sample. After washing of the labeled material on Centricon columns, 5ug of labeled DNA is used for hybridization.
 
Channel 2
Source name L3_8wg16
Organism Drosophila melanogaster
Characteristics reference: input
Treatment protocol No treatment
Growth protocol 1. y; bw cn sp flies are cultivated in cages with apple juice agar plates covered with yeast powder. 2. For a collection of third instar larvae (L3), new plates are added after a 2 hours pre-egglaying at 9 am and flies are allowed to lay eggs for 24 hours. Plates are then kept at 25C for another 48 hours. 3. L3 larvae are collected at 8.45 am using a filter mesh and a brush. L3 larvae are the larvae not going through the first mesh. They are rinsed with EWB and cross-linked at 9 am in 1.8% formaldehyde at room temperature for 15 min.
Extracted molecule genomic DNA
Extraction protocol Drosophila samples are crushed in presence of 1.8% of formaldehyde for 15 minutes. After washing, the material is sonicated for 15 minutes to solubilize the chromatin. After centrifugation, the supernatant containing soluble chromatin is collected for IPs. Specific antibodies are added to the chromatin extract while one aliquot will be treated for DNA extraction corresponding to the reference samples. ChIP are carried overnight at room temperature. Protein A Sepharose beads are used to pull down the chromatin bound antibodies. After washes and finally elution, the DNA corresponding to the IP'd material is extracted and purified. Amplification of the DNA is done by linker-mediated PCR and used for labeling.
Label Cy5
Label protocol 2 ug of amplified IP DNA are used for random primer labeling reaction (invitrogen). Cy3-dCTP is incorporated for the ChIP samples while Cy5-dCTP is incorporated for the Input chromatin sample. After washing of the labeled material on Centricon columns, 5ug of labeled DNA is used for hybridization.
 
 
Hybridization protocol The hybridization solution is composed of 5 ug each of Cy3- and Cy5-labeled DNA, 50 ug of salmon sperm DNA, Agilent Blocking Agent and Agilent Hyb Buffer. The mixture is heated to 95*C for 3 min and then 37*C for 30 minutes immediately prior to hybridization. Samples are hybridized for 40 hours at 65*C. After hybridization the slides are washed in Agilent Wash Buffer 1 for 5 minutes at room temperature and then in Agilent Wash Buffer 2 for 5 minutes at 31*C.
Scan protocol Channel 1 & 2 are for the Agilent arrays are scanned on Agilent's DNA Microarray Scanner G2505B at a resolution of 5 microns. Data is extracted from the images using Agilent's Feature Extraction Software 9.5.3.1.
Channel 1 & 2 are for the Agilent arrays are scanned on Agilent's DNA Microarray Scanner G2505B at a resolution of 5 microns. Data is extracted from the images using Agilent's Feature Extraction Software 9.5.3.1.
Description L3_8wg16
Data processing We preprocessed microarray data to normalize it and reduce experimental noise as described in Qi et al. (Qi et al., Nature biotechnology 2006). In short, the raw intensities from each channel was divided by the median intensity from that channel before computing a ratio to arrive at a median adjusted ratio. We further subtracted average value of negative control probes on the array and then added one as a regularization parameter.
 
Submission date Jun 18, 2009
Last update date Aug 19, 2013
Contact name Kevin P. White
E-mail(s) kpwhite@uchicago.edu
Organization name University of Chicago
Department Institute for Genomics and Systems Biology
Street address 900 E. 57th STR. 10th FL.
City Chicago
State/province IL
ZIP/Postal code 60615
Country USA
 
Platform ID GPL6951
Series (2)
GSE15292 Drosophila at different time points of development: ChIP-chip, ChIP-seq, RNA-seq
GSE16702 ChIP-chip of PolII in Drosophila at different time points of development

Data table header descriptions
ID_REF
VALUE Normalized log ratios between the Cy3 channel and the Cy5 channel intensities.

Data table
ID_REF VALUE
125813 -0.295954280797242
211284 -0.0181137709106619
116584 0.0480014805196303
3459 1.25961245743858
204749 0.212192755127571
36909 0.167919910854727
219799 -0.308273914073275
115177 -0.104329725902682
191452 -0.215493320209511
80970 0.376473702741852
70521 0.339976789161605
173479 -0.153886110753353
114558 0.588819381754198
224367 -0.176401937125657
30370 0.397917478208616
11193 -0.183824549305575
55621 0.0244540455442017
23522 -0.239897549462733
135143 0.169716067914042
241647 0.247549540484357

Total number of rows: 237895

Table truncated, full table size 5814 Kbytes.




Supplementary file Size Download File type/resource
GSM418600.txt.gz 67.6 Mb (ftp)(http) TXT
Processed data included within Sample table

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