DNA methylation in Arabidopsis thaliana
Ontology highlight
ABSTRACT:
ORGANISM(S): Arabidopsis thaliana
PROVIDER: GSE1355 | GEO | 2004/06/12
SECONDARY ACCESSION(S): PRJNA90105
REPOSITORIES: GEO
Similar Datasets
Project description:The purpose of the McrBC methylation microarray assay is to determine which regions of a genome are methylated versus those that are unmethylated in a single Arabidopsis thanliana genotype. McrBC is a methylation-sensitive enzyme that restricts DNA only at purine-Cmethyl half sites when separated between 50bp and 3kb. A designated amount of DNA from a particular genotype is sheared to a size range of 1kb-10kb using nebulization. We restrict half of the nebulized DNA with McrBC, and the methylated fraction is then removed from the unmethylated fraction through gel purification of DNA fragments greater than 1kb.* The remaining nebulized DNA is subjected to the same gel purification scheme, but with no McrBC treatment. In a single hybridization, the untreated sample is labeled with Cy5 and the McrBC-treated sample with Cy3. Thus, after labeling and microarray hybridization, the ratio of normalized Cy5 to normalized Cy3 represents the relative methylation at the sequence represented by the spot on the microarray. Dye swap analysis is carried out to take account of experimental variation by repeating the hybridization with identical samples labeled with Cy3 and Cy5, respectively. The two samples in this series are complementary hybridizations in a dye-swap analysis. This is the normalized result of the paired dye swap samples VC121 and VC127. The ANOVA model of Kerr, Martin and Churchill (2000) was used to analyze the data from the dye-swap experiments, with terms included to account for gene, dye-by-gene, treatment-by-gene, and random error terms. These samples were not subjected to hypothesis testing. Therefore, P-values are reported as -1 and no features are flagged as significantly methylated. Keywords: other
2004-06-12 | GSE1329 | GEO
Project description:DNA methylation in wild type bolting plants, wild type seedlings, and ddm1 seedlings. The purpose of the McrBC methylation microarray assay is to determine which regions of a genome are methylated versus those that are unmethylated in a single Arabidopsis thanliana genotype. McrBC is a methylation-sensitive enzyme that restricts DNA only at purine-Cmethyl half sites when separated between 50bp and 3kb. A designated amount of DNA from a particular genotype is sheared to a size range of 1kb-10kb using nebulization. We restrict half of the nebulized DNA with McrBC, and the methylated fraction is then removed from the unmethylated fraction through gel purification of DNA fragments greater than 1kb.* The remaining nebulized DNA is subjected to the same gel purification scheme, but with no McrBC treatment. In a single hybridization, the untreated sample is labeled with Cy5 and the McrBC-treated sample with Cy3. Thus, after labeling and microarray hybridization, the ratio of normalized Cy5 to normalized Cy3 represents the relative methylation at the sequence represented by the spot on the microarray. Dye swap analysis is carried out to take account of experimental variation by repeating the hybridization with identical samples labeled with Cy3 and Cy5, respectively. This SuperSeries is composed of the following subset Series: GSE1329: DNA methylation in wild-type bolting Arabidopsis thaliana plants GSE1330: DNA methylation in ddm1 seedling Arabidopsis thaliana plants GSE1331: VC133+137, DNA methylation in ddm1 seedling Arabidopsis thaliana plants GSE1332: VC134+136, DNA methylation in wild-type seedling Arabidopsis thaliana plants Refer to individual Series
2010-06-09 | E-GEOD-1355 | biostudies-arrayexpress
Project description:The purpose of the McrBC methylation microarray assay is to determine which regions of a genome are methylated versus those that are unmethylated in a single Arabidopsis thaliana genotype. McrBC is a methylation-sensitive enzyme that restricts DNA only at purine-Cmethyl half sites when separated between 50bp and 3kb. A designated amount of DNA from a particular genotype is sheared to a size range of 1kb-10kb using nebulization. We restrict half of the nebulized DNA with McrBC, and the methylated fraction is then removed from the unmethylated fraction through gel purification of DNA fragments greater than 1kb.* The remaining nebulized DNA is subjected to the same gel purification scheme, but with no McrBC treatment. In a single hybridization, the untreated sample is labeled with Cy5 and the McrBC-treated sample with Cy3. Thus, after labeling and microarray hybridization, the ratio of normalized Cy5 to normalized Cy3 represents the relative methylation at the sequence represented by the spot on the microarray. Dye swap analysis is carried out to take account of experimental variation by repeating the hybridization with identical samples labeled with Cy3 and Cy5, respectively. ddm1 seedlings, 9 days old. The two samples in this series are complementary hybridizations in a dye-swap analysis. This is the normalized result of the paired dye swap samples VC131 and VC135. The ANOVA model of Kerr, Martin and Churchill (2000) was used to analyze the data from the dye-swap experiments, with terms included to account for gene, dye-by-gene, treatment-by-gene, and random error terms. The style of hypothesis test proposed by Black and Doerge (2002) was applied to each of the features represented on each array, with rejection of the null hypothesis indicating a significant change in fluorescence intensity. To account for the number of hypothesis tests being made, and thus provide some level of error rate control, significance was assessed using both family-wise error rate (FWER) and false discovery rate (FDR) controlling methods. The step-down multiple comparisons procedure of Holm (1979) was used to control the FWER below alpha = 0.01, while the step-up procedure of Benjamini and Hochberg (1995) was used to control the FDR below alpha = 0.01. For the purposes of this experiment, the hypotheses were assumed to be independent. Features found to be significantly enriched for DNA methylation after hypothesis-testing with a controlled error rate are flagged in the last two columns. Keywords: other
2004-06-12 | GSE1330 | GEO
Project description:The purpose of the McrBC methylation microarray* assay is to determine which regions of a genome are methylated versus those that are unmethylated in a single Arabidopsis thanliana genotype. McrBC is a methylation-sensitive enzyme that restricts DNA only at purine-Cmethyl half sites when separated between* 50bp and 3kb. A designated amount of DNA from a particular genotype is sheared to a size range of 1kb-10kb using nebulization. We restrict half of the nebulized DNA with McrBC, and the methylated fraction is then removed from the unmethylated fraction through gel purification of DNA fragments greater than 1kb.* The remaining nebulized DNA is subjected to the same gel purification scheme, but with no McrBC treatment. In a single hybridization, the untreated sample is labeled with Cy5 and the McrBC-treated sample with Cy3.* Thus, after labeling and microarray hybridization, the ratio of normalized Cy5 to normalized Cy3 represents the relative methylation at the sequence represented by the spot on the microarray.* Dye swap analysis is carried out to take account of experimental variation by repeating the hybridization with identical samples labeled with Cy3 and Cy5, respectively. The two samples in this series are complementary hybridizations in a dye-swap analysis. wild-type seedlings, 9 days old. Below is the normalized result of the paired dye swap samples VC134 and VC136. The ANOVA model of Kerr, Martin and Churchill (2000) was used to analyze the data from the dye-swap experiments, with terms included to account for gene, dye-by-gene, treatment-by-gene, and random error terms. The style of hypothesis test proposed by Black and Doerge (2002) was applied to each of the features represented on each array, with rejection of the null hypothesis indicating a significant change in fluorescence intensity. To account for the number of hypothesis tests being made, and thus provide some level of error rate control, significance was assessed using both family-wise error rate (FWER) and false discovery rate (FDR) controlling methods. The step-down multiple comparisons procedure of Holm (1979) was used to control the FWER below alpha = 0.01, while the step-up procedure of Benjamini and Hochberg (1995) was used to control the FDR below alpha = 0.01. For the purposes of this experiment, the hypotheses were assumed to be independent. Features found to be significantly enriched for DNA methylation after hypothesis-testing with a controlled error rate are flagged in the last two columns. Keywords: other
2004-06-12 | GSE1332 | GEO
Project description:This series is a technical replicate of VC133+135. The purpose of the McrBC methylation microarray assay is to determine which regions of a genome are methylated versus those that are unmethylated in a single Arabidopsis thanliana genotype. McrBC is a methylation-sensitive enzyme that restricts DNA only at purine-Cmethyl half sites when separated between 50bp and 3kb. A designated amount of DNA from a particular genotype is sheared to a size range of 1kb-10kb using nebulization. We restrict half of the nebulized DNA with McrBC, and the methylated fraction is then removed from the unmethylated fraction through gel purification of DNA fragments greater than 1kb. The remaining nebulized DNA is subjected to the same gel purification scheme, but with no McrBC treatment. In a single hybridization, the untreated sample is labeled with Cy5 and the McrBC-treated sample with Cy3. Thus, after labeling and microarray hybridization, the ratio of normalized Cy5 to normalized Cy3 represents the relative methylation at the sequence represented by the spot on the microarray. Dye swap analysis is carried out to take account of experimental variation by repeating the hybridization with identical samples labeled with Cy3 and Cy5, respectively. The two samples in this series are complementary hybridizations in a dye-swap analysis. ddm1 seedlings, 9 days old. Below is the normalized result of the paired dye swap samples VC133 and VC137. The ANOVA model of Kerr, Martin and Churchill (2000) was used to analyze the data from the dye-swap experiments, with terms included to account for gene, dye-by-gene, treatment-by-gene, and random error terms. The style of hypothesis test proposed by Black and Doerge (2002) was applied to each of the features represented on each array, with rejection of the null hypothesis indicating a significant change in fluorescence intensity. To account for the number of hypothesis tests being made, and thus provide some level of error rate control, significance was assessed using both family-wise error rate (FWER) and false discovery rate (FDR) controlling methods. The step-down multiple comparisons procedure of Holm (1979) was used to control the FWER below alpha = 0.01, while the step-up procedure of Benjamini and Hochberg (1995) was used to control the FDR below alpha = 0.01. For the purposes of this experiment, the hypotheses were assumed to be independent. Features found to be significantly enriched for DNA methylation after hypothesis-testing with a controlled error rate are flagged in the last two columns. Keywords: other
2004-06-12 | GSE1331 | GEO
Project description:To assess changes in DNA methylation state associated with breast cancer we analyzed DNA from normal and cancerous breast specimens on CpG islands microarray using methylation-sensitive enzyme McrBC for target preparation. Cy3 was used for McrBC cut sample, Cy5 was used for reference Mock sample.
2006-11-03 | E-MEXP-881 | biostudies-arrayexpress
Project description:We describe an optimized microarray method for identifying genome-wide CpG island methylation called Microarray-based Methylation Assessment of Single Samples (MMASS) which directly compares methylated to unmethylated sequences within a single sample. To improve previous methods we used bioinformatic analysis to predict an optimised combination of methylation-sensitive enzymes that had the highest utility for CpG-island probes and different methods to produce unmethylated representations of test DNA for more sensitive detection of differential methylation by hybridization. Subtraction or methylation-dependent digestion with McrBC was used with optimized (MMASS-v2) or previously described (MMASS-v1, MMASS-sub) methylation-sensitive enzyme combinations and compared to a published McrBC method. Comparison was performed using DNA from the cell line HCT116. We show that the distribution of methylation microarray data is inherently skewed and requires exogenous spiked controls for normalization and that analysis of digestion of methylated and unmethylated control sequences together with linear fit models of replicate data showed superior statistical power for the MMASS-v2 method. Comparison to previous methylation data for HCT116 and validation of CpG islands from PXMP4, SFRP2, DCC, RARB and TSEN2 confirmed the accuracy of MMASS-v2 results. The MMASS-v2 method offers improved sensitivity and statistical power for high-throughput microarray identification of differential methylation. Keywords: Methylation genomic hybridizations.
2006-10-31 | GSE5326 | GEO
Project description:We have systematically profiled DNA methylation at promoter CpG islands (CGIs) in ovarian cancer. Epithelial ovarian tumours, excluding mucinous and clear cell cancers, prospectively collected through a cohort study, were analyzed by differential methylation hybridization (DMH) (Nouzova M et al, 2004) in duplicates. The loci targeted by the custom-designed microarray are the promoter CpG islands (Gardiner-Garden and Frommer, 1987) of the genes involved in the Wnt, p53, AKT/mTOR, BRCA1/2 and Redox pathways, DNA repair (HR, NHEJ and MMR), FA family and IgLON family. 111 ovarian tumor samples were assayed by DMH in duplicates. McrBC digested (Cy5) and undigested (Cy3) samples were competitively hybridized on the Agilent custom-designed microarrays 8x15k.
2011-06-01 | E-GEOD-23240 | biostudies-arrayexpress
Project description:The microarrays were subjected to two-color hybridization using Cy5 and Cy3 dyes incorporated in the cDNAs synthesized from total RNA samples of strains. We compared each gene’s transcription level between the wild-type (WT) strain 13 (labeled by Cy5) and the virX-mutant strain (TS186) (labeled by Cy3) on a single DNA microarray.
2012-10-01 | GSE37998 | GEO
Project description:The microarrays were subjected to two-color hybridization using Cy5 and Cy3 dyes incorporated in the cDNAs synthesized from total RNA samples of strains. We compared each gene’s transcription level between the wild-type (WT) strain 13 (labeled by Cy5) and the VirR-mutant strain (TS133) or VR-RNA-mutant strain (TS140) (both labeled by Cy3) on a single DNA microarray. Keywords: gene regulation in time course
2009-09-17 | GSE12833 | GEO