Density Transfer Data for Lachancea waltii DNA Replication Profile
Ontology highlight
ABSTRACT:
ORGANISM(S): Lachancea waltii
SUBMITTER: Sara Di Rienzi
PROVIDER: E-GEOD-35155 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:To identify origins of replication in Lachancea waltii by mapping regions of ssDNA that are enriched in S phase. L. waltii cells are grown in the presence of hydroxyurea, which slows replication forks and causes the accumulation of ssDNA at the replication fork.
2012-05-09 | E-GEOD-35253 | biostudies-arrayexpress
Project description:Cell cycle arrest and transcriptional responses to ionizing radiation (IR)-induced DNA damage were quantified in telomerase-expressing human diploid fibroblasts. Assays of clonal expansion established 1.5 Gy IR as the D0 dose in three fibroblast lines and this dose was used in all subsequent analyses. Fibroblasts exhibited >90% arrest of progression from G2 to M at 2 h and from G1 to S at 6 and 12 h post-IR. Normal rates of DNA synthesis and mitosis 6 and 12 h after irradiation caused the S and M compartments to empty by over 70% at 24 h. Microarray monitored global gene expression in IR-treated cells and a new microarray analysis algorithm, EPIG, identified nine IR-responsive patterns of gene expression including a dominant p53-dependent G1 checkpoint response. Many p53 target genes, like CDKN1A, GADD45, BTG2 and PLK3, were significantly up-regulated at 2 h post-IR while many genes whose expression is regulated by E2F family transcription factors, including CDK2, CCNE1, CDC6, CDC2, MCM2, were significantly down-regulated at 24 h post-IR. Numerous genes that participate in DNA metabolism were also markedly repressed in arrested fibroblasts as a result of cell synchronization behind the G1 checkpoint. However, cluster and principal component analyses of gene expression revealed a profile of gene expression 24 h after IR with similarity to that of G0 growth quiescence. These results demonstrate a highly stereotypic pattern of response to IR that reflects primarily synchronization behind the G1 checkpoint but with prominent induction of additional markers of G0 quiescence such as GAS1. Experiment Overall Design: Logarithmically growing cells were treated with 1.5 Gy IR or sham, and harvested at 2, 6 or 24 h after the treatment. Total RNA was isolated using Qiagen RNeasy kit. The quality of all RNA samples was confirmed using an Agilent 2100 Bioanalyzer. Microarray analysis was then performed: briefly, 1 µg of sample RNA and global reference RNA (Stratagene) were converted to cDNA with reverse transcriptase then amplified using T7 RNA polymerase while labeling with either Cy3-dUTP or Cy5-dUTP (Agilentâs Low RNA Input Linear Amplification Kit). The quality of each labeled cRNA was evaluated using an Agilent 2100 Bioanalyzer prior to hybridization. 750ng of Cy3 and Cy5-labeled cRNA were used in the hybridization. The labeled cRNA from sham- or IR-treated samples was hybridized with the labeled global reference cRNA on an Agilent 22k human 1A array in a hybridization oven (Robbins Scientific Model 400, 1040-60-1AG) at 60oC for 17 h. Hybridization of sample RNA against reference RNA was done twice with dye swap. Following hybridization, the arrays were scanned using the Agilent DNA Microarray Scanner with SureScan® Technology and microarray images were analyzed using Agilent Feature Extraction Software (v7.1). The gene expression level was presented as ratio of sample intensity against reference intensity.
2008-06-15 | E-GEOD-6902 | biostudies-arrayexpress
Project description:The changes in global gene expression in response to DNA damage may derive from either direct induction or repression by transcriptional regulation or indirectly by synchronization of cells to specific cell cycle phases, such as G1 or G2. We developed a model that successfully estimated the expression levels of >400 cell-cycle-regulated genes in normal human fibroblasts based on the proportions of cells in each phase of the cell cycle. By isolating effects on the gene expression associated with the cell cycle phase redistribution after genotoxin treatment, the direct transcriptional target genes were distinguished from genes for which expression changed secondary to cell synchronization. Application of this model to ionizing radiation (IR)-treated normal human fibroblasts identified 150 of 406 cycle-regulated genes as putative direct transcriptional targets of IR-induced DNA damage. Changes in expression of these genes after IR treatment derived from both direct transcriptional regulation and cell cycle synchronization. Experiment Overall Design: Normal human fibroblasts were synchronized and harvested at G0, G1, S G2 and M cell cycle phase, and logarithmically growing cells were treated with 1.5 Gy IR or sham, and harvested at 2, 6 or 24 h after the treatment. Total RNA was isolated using Qiagen RNeasy kit. The quality of all RNA samples was confirmed using an Agilent 2100 Bioanalyzer. Microarray analysis was then performed: briefly, 1 µg of sample RNA and global reference RNA (Stratagene) were converted to cDNA with reverse transcriptase then amplified using T7 RNA polymerase while labeling with either Cy3-dUTP or Cy5-dUTP (Agilentâ??s Low RNA Input Linear Amplification Kit). The quality of each labeled cRNA was evaluated using an Agilent 2100 Bioanalyzer prior to hybridization. 750ng of Cy3 and Cy5-labeled cRNA were used in the hybridization. The labeled cRNA from sham- or IR-treated samples was hybridized with the labeled global reference cRNA on an Agilent 22k human 1A array in a hybridization oven (Robbins Scientific Model 400, 1040-60-1AG) at 60oC for 17 h. Hybridization of sample RNA against reference RNA was done twice with dye swap. Following hybridization, the arrays were scanned using the Agilent DNA Microarray Scanner with SureScan® Technology and microarray images were analyzed using Agilent Feature Extraction Software (v7.1). The gene expression level was presented as ratio of sample intensity against reference intensity.
2008-06-15 | E-GEOD-7075 | biostudies-arrayexpress
Project description:The relationships between profiles of global gene expression and DNA damage checkpoint functions were studied in cells from patients with ataxia telangiectasia (AT). Three telomerase-expressing AT fibroblast lines displayed the expected hypersensitivity to ionizing radiation (IR) and defects in DNA damage checkpoints. Profiles of global gene expression in AT cells were determined at 2, 6 and 24 h after treatment with 1.5 Gy IR or sham-treatment, and were compared to those previously recognized in normal human fibroblasts. Under basal conditions 160 genes or ESTs were differentially expressed in AT and normal fibroblasts, and these were associated by gene ontology with insulin-like growth factor binding and regulation of cell growth. Upon DNA damage, 1091 gene mRNAs were changed in at least two of the three AT cell lines. When compared with the 1811 genes changed in normal human fibroblasts after the same treatment, 715 were found in both AT and normal fibroblasts, including most genes categorized by gene ontology into cell cycle, cell growth and DNA damage response pathways. However, the IR-induced changes in these 715 genes in AT cells usually were delayed or attenuated in comparison to normal cells. The reduced change in DNA-damage-response genes and the attenuated repression of cell-cycle-regulated genes may account for the defects in cell cycle checkpoint function in AT cells. The observation of attenuated and not ablated checkpoint responses in AT cells supports a hypothesis that the ATM- and rad3-related checkpoint kinase ATR also responds to IR-induced DNA damage and complements ATM signaling. Experiment Overall Design: Logarithmically growing cells were treated with 1.5 Gy IR or sham, and harvested at 2, 6 or 24 h after the treatment. Total RNA was isolated using Qiagen RNeasy kit. The quality of all RNA samples was confirmed using an Agilent 2100 Bioanalyzer. Microarray analysis was then performed: briefly, 1 µg of sample RNA and global reference RNA (Stratagene) were converted to cDNA with reverse transcriptase then amplified using T7 RNA polymerase while labeling with either Cy3-dUTP or Cy5-dUTP (Agilentâs Low RNA Input Linear Amplification Kit). The quality of each labeled cRNA was evaluated using an Agilent 2100 Bioanalyzer prior to hybridization. 750ng of Cy3 and Cy5-labeled cRNA were used in the hybridization. The labeled cRNA from sham- or IR-treated samples was hybridized with the labeled global reference cRNA on an Agilent 22k human 1A array in a hybridization oven (Robbins Scientific Model 400, 1040-60-1AG) at 60oC for 17 h. Hybridization of sample RNA against reference RNA was done twice with dye swap. Following hybridization, the arrays were scanned using the Agilent DNA Microarray Scanner with SureScan® Technology and microarray images were analyzed using Agilent Feature Extraction Software (v7.1). The gene expression level was presented as ratio of sample intensity against reference intensity.
2008-06-15 | E-GEOD-6971 | biostudies-arrayexpress
Project description:Understanding cell-type-specific epigenetic codes on a global level is a major challenge after the sequencing of the human genome has been completed. Here we applied methyl-CpG immunoprecipitation (MCIp) to obtain comparative methylation profiles of coding and noncoding genes in three human tissues, testis, brain, and monocytes. Forty-four mainly testis-specific promoters were independently validated using bisulfite sequencing or single-gene MCIp, confirming the results obtained by the MCIp microarray approach. We demonstrate the previously unknown somatic hypermethylation at many CpG-rich, testis-specific gene promoters, in particular in ampliconic areas of the Y chromosome. We also identify a number of miRNA genes showing tissue-specific methylation patterns. The comparison of the obtained tissue methylation profiles with corresponding gene expression data indicates a significant association between tissue-specific promoter methylation and gene expression, not only in CpG-rich promoters. In summary, our study highlights the exceptional epigenetic status of germ-line cells in testis and provides a global insight into tissue-specific DNA methylation patterns. Keywords: MCIp-on-Chip The promoter hypomethylation profiles of the two somatic tissues (monocytes and brain) were compared to human testis (reference). The set includes two hybridisations with independent testis samples for each comparison. Each comparison uses a set of two microarrays.
2007-08-07 | E-GEOD-5548 | biostudies-arrayexpress
Project description:In order to identify methylation changes in prostate cancer, we performed a genome-wide analysis of DNA methylation using Agilent human CpG island arrays. We then chose specific genes to validate methylation both in the same cases as were hybridized to the array (using quantitative EpiTYPER analysis) and in an independent series of prostate cancer samples (using MethyLight quantitative methylation specific PCR). We specifically chose low grade (Gleason score 6 cases) and high grade (Gleason score 8 cases) to discover methylated genes/loci that may be involved in the progression to a higher grade of prostate cancer. We collected 20 specimens consisting of 10 Gleason 6 and 10 Gleason 8 prostate cancers, and compared these to a reference lymphocyte pool (6 age matched, healthy men) to determine cancer associated methylation changes as well as disease progression associated methylation changes. We performed the differential methylation hybridization procedure as described by Yan et al. (Methods, 2002) on each case to enrich for methylated DNA. Each specimen in the reference pool underwent the same enrichment with amplicons being pooled at the end of the procedure. Each prostate cancer case was subsequently co-hybridized to the microarray with the reference pool.
2009-03-26 | E-GEOD-15298 | biostudies-arrayexpress
Project description:Low vitamin D status has been implicated in the progression of inflammatory bowel disease (IBD). This study used interleukin (IL)-10 knockout (KO) mice, that develop an intestinal inflammation when housed in a non-sterile environment, to determine if supplementation with vitamin D throughout life impacts colonic gene expression. Results provide important information on the intestinal response to vitamin D in inflamed mice. Female IL-10 knock out mice were randomized to 25 (Low, L) or 5000 (High, H) IU vitamin D/kg of diet throughout pregnancy and lactation. At weaning, offspring received the same or opposite diet as their mother until age 3 months. This resulted in four vitamin D interventions: HH, HL, LH, or LL where the first letter represents the diet consumed by dams during pregnancy and lactation and the second letter represents the diet consumed by offspring from weaning through to 3 months of age. Global gene expression was analyzed in the proximal colon of 3 months old mice (n=6 per group, for a total of 24 samples; samples came from different litters and moms IDs are given in the samples table below). Samples were stored at -80C.
2015-01-02 | E-GEOD-61111 | biostudies-arrayexpress
Project description:We examined the major patterns of changes in gene expression in mouse splenic B cells in response to stimulation with 33 single ligands for 0.5, 1, 2, and 4 h. We found that ligands known to directly induce or costimulate proliferation, namely, anti-IgM (anti-Ig), anti-CD40 (CD40L), LPS, and, to a lesser extent, IL-4 and CpG-oligodeoxynucleotide (CpG), induced significant expression changes in a large number of genes. The remaining 28 single ligands produced changes in relatively few genes, even though they elicited measurable elevations in intracellular Ca2+ and cAMP concentration and/or protein phosphorylation, including cytokines, chemokines, and other ligands that interact with G protein-coupled receptors. A detailed comparison of gene expression responses to anti-Ig, CD40L, LPS, IL-4, and CpG indicates that while many genes had similar temporal patterns of change in expression in response to these ligands, subsets of genes showed unique expression patterns in response to IL-4, anti-Ig, and CD40L.
2004-12-08 | E-GEOD-2050 | biostudies-arrayexpress
Project description:total RNA from mouse (male c57BL/6) spleen labeled with Cy3 vs total RNA from mouse (male c57BL/6) B cells treated with Neurokinin B (NEB) labeled with Cy5- time course with repeats
2010-06-10 | E-GEOD-2464 | biostudies-arrayexpress
Project description:LNCaP prostate cancer cells were treated with and without 100?g/ml Emetine Dihydrochloride Hydrate (Fluka, Buchs, Swizerland). Both Emetine-treated and untreated control cells were then incubated at 37°C for 10 hours. After the incubation, the first time point (0 min) was harvested for both treated and untreated cells. Simultaneously, Actinomycin D (Sigma-Aldrich, St Louis, MO) with the final concentration of 5ug/ml, was added to the remaining treated and untreated cells to stop new transcription. Time points of 10min, 30min, 1h, 2h, and 4h were harvested in both groups for most of the cell lines. Cell pellets were snap-frozen and mRNA extracted by using FastTrack kit (Invitrogen) according to the manufacturerâs instructions. For each time point, the untreated sample was hybridized against the Emetine-treated equivalent. Four ug of untreated mRNA was labeled with Cy5-dUTP and four ug of Emetine-treated mRNA with Cy3-dUTP (Amersham Biosciences, Piscataway, NJ) as previously described (Mousses et al, 2000). Image analysis was done by DeArray software. Average intensities of the tumor samples were divided by the average intensities of the reference sample at each microarray spot after background intensity subtraction. Within-slide normalization was performed with ratio statistics method using housekeeping genes as described previously (Chen et al, 1997). The data were quality filtered with ratio quality method (Chen et al, 2002), which computes a quality value for each ratio. The scale for the quality values is from zero (poor quality) to one (good quality). Here, all ratios having quality value below 0.5 were discarded from the subsequent analysis.
2010-06-09 | E-GEOD-1488 | biostudies-arrayexpress