NCBI Logo
GEO Logo
   NCBI > GEO > Accession DisplayHelp Not logged in | LoginHelp
GEO help: Mouse over screen elements for information.
          Go
Sample GSM1333898 Query DataSets for GSM1333898
Status Public on Aug 05, 2014
Title DamID Dam control 2
Sample type SRA
 
Source name Haemogenic Endothelium
Organism Mus musculus
Characteristics cell line: iDamko
strain: 129
Growth protocol ES cell–derived haemogenic endothelium cells were routinely generated by isolating FLK1+ cells from d3.25 embryonic eody differentiations. FLK1+ cells where maintained on gelatin coated plates in liquid blast medium (IMDM supplemented with 10% FCS, P/S, 2mM L-Glutamine, 20μg/ml transferrin, 0.45mM MTG, 25μg/ml AA, 15% D4T conditioned medium, 5ng/ml VEGF and 10ng/ml IL6). After 2 days of liquid blast culture haemogenic endothelial cells where isolated either by sorting for FLK1+ or for the cKIT+ TIE2+ CD41- phenotype.
Extracted molecule genomic DNA
Extraction protocol Genomic DNA was isolated from snap frozen samples using the Wizard Genomic DNA Purification Kit (Promega) according to manufacturers instructions and DamID samples where prepared as described (Vogel et al. Nat Protoc 2, 1467-1478, 2007)
For DamID-seq (ChIP-seq) standard barcoded fragment libraries were prepared as described in the Applied Biosystems SOLiD 4 Standard Library Preparation Manual (4445673)
 
Library strategy ChIP-Seq
Library source genomic
Library selection ChIP
Instrument model AB SOLiD System 3.0
 
Description FACS: cKIT+ TIE2+ CD41-
Data processing Sequencing reads were aligned to mm9 genome using SHRiMP2 with default settings. Reads aligning to multiple loci were discarded.
The BioConductor package BayesPeak was used to call peaks from the uniquely aligned reads for control and test samples seperrately, using the default settings. Peaks with a posterior probability > 0.9 were kept for further analysis.
Isolated peaks (that do not overlap with a peak in the control sample) were retained for subsequent analysis. We then identified all instances where one or more peaks from the test and control samples overlapped and extend the boundaries of these regions to contain all contiguous signal (irrespective of whether that came from control or test samples). We then calculated the RPKM (number of reads per kilo base per million reads) in the region from the test sample and the control sample respectively and ranked regions by the difference in RPKM between the test and control samples (i.e. ∆RPKM = RPKM_test - RPKM_control)
We selected the 10% of regions with the greatest difference and filtered further to discard loci where fold change of test to control, i.e. RPKM_test/RPKM_control, < 2. Peaks in the test sample overlapping with these remaining regions were added to the set of isolated peaks for further analysis.
We applied the Poisson model based scan statistic method (Kulldorff, M.Theory and Methods, 1997; 26:1481-1496) to this set of peaks to find peak-enriched regions in the genome. A 2000bp window was scanned along each chromosome at 400bp increments. At each position of the sliding window, we calculated the number of bases within the window corresponding to a peak. This value, together with length of the window, was used to compute the value of the scan statistic. Monte Carlo sampling was used to establish an approximate distribution of the scan statistic under the null hypothesis.
We selected those windows where the p-value of the scan statistic < 0.05 as peak-enriched windows (PEW) and merged contiguous PEWs to generate larger, peak-enriched regions (PERs), and trimmed the 5' and 3' boundaries of each region to remove nucleotides that do not overlap with any peak. Finally, we merged adjacent PERs closer than 300bp.
PERs were mapped to genome annotation using ENSEMBL (v66) via the BioConductor package annmap, and retaining PERs that overlapped, or within 30kb of a gene. Where multiple genes mapped to a single PER, the closest gene was selected in order to generate a PER_to_gene mapping for each test sample
Genome_build: mm9
 
Submission date Feb 24, 2014
Last update date May 15, 2019
Contact name michael lie-a-ling
E-mail(s) Michael.Lie-A-Ling@ics.manchester.ac.uk
Organization name Cancer Research UK Manchester Institute
Department Stem Cell Biology
Street address The University of Manchester | Wilmslow Road
City manchester
ZIP/Postal code M204BX
Country United Kingdom
 
Platform ID GPL9318
Series (2)
GSE55308 RUNX1 positively regulates a cell adhesion and migration program in murine hemogenic endothelium prior to blood emergence (DamID-seq)
GSE55335 RUNX1 positively regulates a cell adhesion and migration program in murine hemogenic endothelium prior to blood emergence
Relations
BioSample SAMN02664694
SRA SRX475919

Supplementary data files not provided
SRA Run SelectorHelp
Raw data are available in SRA
Processed data are available on Series record

| NLM | NIH | GEO Help | Disclaimer | Accessibility |
NCBI Home NCBI Search NCBI SiteMap