Interindividual comparison of methylation profiling by MSAM
ABSTRACT: Interindividual variation in methylation profiling of human DNA samples were detected using two-tissue screening by MSAM. 0.5ug of DNA was serially digested with SmaI and XmaI followed by an adaptor ligation and adaptor mediated PCR amplification HF (hair follicle) and PBL (Peripheral Blood Leukocyte) DNA samples for 8 different individuals, two-color experiment, interindividual paired comparison (same sex and age)
Project description:Investigate the genome-wide DNA methylation changes in the mouse hypothalamus during the suckling period. Hypothalami were collected from new born (P0) mice, or mice of 21 day-old (P21). Two-color experiment was performed as paired comparison of P21 vs. P0 with two biological replicates. Genome-wide DNA methylation changes from P0 to P21 were detected by MSAM. As a brief description of the MSAM: 500ng of genomic DNA was serially digested with SmaI and XmaI followed by an adaptor ligation and adaptor mediated PCR amplification and then cohybridization.
Project description:Investigate the persistent effects of early postnatal overnutrition on the developmental establishment of the DNA methylation in the mouse hypothalamus. Early postnatal overnutrition was induced in mice by reducing the litter size from normally 9 (C) to 4 (SL) pups per litter. Hypothalami were collected from both C and SL mice at the age of postnatal day 180 (P180). Genome-wide DNA methylation difference between SL and C were detected by MSAM. Equal amount of genomic DNA from 5 hypothalami of the same group were pooled as one MSAM sample. Two pooled DNA samples for each group were used for comparison that meant total 10 hypothalami for each group. 500ng pooled DNA was serially digested with SmaI and XmaI followed by adaptor ligation and PCR amplification. Two cohybridizations were performed to compare DNA methylation between SL and C hypothalami, with day swap.
Project description:The goal is to compare the DNA methylation patterns between ARH and PVH to examine to what extent DNA methylation is region specific in genome scale. ARH and PVH were micro-dissected from mice brains. Each 7 pieces of ARH or PVH were pooled and used for DNA methylation comparison by methylation specific amplification microarray (MSAM). As a brief description of the MSAM: 500ng of genomic DNA was serially digested with SmaI and XmaI followed by an adaptor ligation and adaptor mediated PCR amplification and then cohybridization. Two-color cohybridizations were performed as paired comparison of PVH vs. ARH with two biological replicates including dye swap.
Project description:Investigate the genome-wide DNA methylation and gene expression changes during human embryonic stem cell differentiation. hESCs (H1 and H13) DNA samples for 3 different differentian stage (D0, undifferentiated;D21, 21 days after undirected differentiation; D90, 90 days after undirected differentiation); two-color experiment, paired comparison (differentiated vs undifferentiated; A & B: two biological replicates). Differentian-stage variation in methylation profiling of human DNA samples were detected by MSAM. 2µg of DNA was serially digested with SmaI and XmaI followed by an adaptor ligation and adaptor mediated PCR amplification. Analysis of differentian-stage variation in gene expression of human mRNA samples were implementd following standard Agilent protocol.
Project description:DNA methylation profiling of colonic mucosal DNA between P90 and P30 mice. 0.5ug of DNA was serially digested with SmaI and XmaI followed by an adaptor ligation and adaptor mediated PCR amplification Two independent P90 to P30 comparisons were performed as follows. Samples were labelled with Cy3 (P30) and Cy5 (P90) and two independent P90 to P30 comparisons were done on a 2x105k methylation specific amplification microarray (MSAM) containing 90,535 probes, covering 77% of the 31,019 SmaI intervals between 200 bp and 2 kb in the mouse genome (average 3.8 probes per interval)
Project description:Human epidemiologic and animal model data indicate that early environmental influences can persistently alter an individual’s risk of obesity. Environmental effects on hypothalamic developmental epigenetics provide a strong candidate mechanism to explain such ‘developmental programming’ of obesity. To advance our understanding of these processes, it is essential to determine to what extent the diversity of hypothalamic cell types is regulated by epigenetic differences, and when these are established. By performing genome-scale DNA methylation profiling in hypothalamic neurons and non-neuronal cells at postnatal day 0 (P0) and P21, we found that most of the DNA methylation differences distinguishing these two cell types are established postnatally. We found dramatic neuron-specific increases in DNA methylation from P0 to P21. Gene ontology analyses indicated that cell-type specific P0 to P21 methylation changes are key regulators of hypothalamic development. Quantitative bisulfite pyrosequencing verified our methylation profiling results in 16 of 16 selected regions. Expression differences were associated with DNA methylation in several genes analyzed. Our data indicate that future studies of hypothalamic epigenetics in developmental programming of obesity will gain far greater sensitivity and insight by examining outcomes at the cell-type specific level. Moreover, our results provide new evidence that early postnatal life is a critical period for murine hypothalamic developmental epigenetics. Hypothalami were dissected from inbred male C57 mice at postnatal day 0 (P0) and P21. Non-neuronal and neuronal nuclei were separated via fluorescence-activated sorting based on staining for the neuron-specific nuclear surface marker NeuN; each sample for sorting was comprised of 2 age-matched hypothalami. Genome-scale DNA methylation profiling was performed by methylation specific amplification coupled with next generation sequencing (MSA-seq) as decribed below (5 independent samples per age).
Project description:Interindividual variation in methylation profiling of human DNA samples were detected using two-tissue screening by MSAM. 0.5ug of DNA was serially digested with SmaI and XmaI followed by an adaptor ligation and adaptor mediated PCR amplification Overall design: HF (hair follicle) and PBL (Peripheral Blood Leukocyte) DNA samples for 8 different individuals, two-color experiment, interindividual paired comparison (same sex and age)
Project description:We describe a simple method, Digital Restriction Enzyme Analysis of Methylation (DREAM), based on sequential DNA digestion with a pair of methylation-blocked and methylation-tolerant neoschizomeric restriction enzymes SmaI/XmaI followed by end repair and ultra-deep sequencing. DREAM provides information on 160,000 unique CpG sites of which 39,000 are in CpG islands, and 33,000 are at transcription start sites (-1 kb to +1 kb) of 13,139 RefSeq genes. We compared DNA methylation values in white blood cells from 4 healthy individuals and found them to be remarkably uniform. Interindividual differences >30% were observed only at 227 of 28,331 (0.8%) of autosomal CCCGGG sites covered by 100+ sequencing reads. Similarly, differences at only 59 sites were observed between the cord and adult blood. Conserved methylation patterns in healthy blood cells contrasted with extensive changes affecting 18-40% of CpG sites in leukemia. The method is cost effective, quantitative (r2=0.93 when compared to bisulfite pyrosequencing), reproducible (r2=0.997), and can detect differences >25% with false positive rate <0.001. Accurate analysis of changes in DNA methylation will be useful in quantifying epigenetic effects of environment and nutrition, correlating developmental epigenetic variation with phenotypes, understanding epigenetics of cancer and chronic diseases, measuring the effects of drugs on DNA methylation or deriving new biological insights into mammalian genomes. Digital restriction enzyme analysis of methylation (DREAM) was performed to determine the DNA methylation profiles of healthy white blood cells from cord blood and adult blood, acute myeloid leukemia bone marrow, and two leukemia cell lines (HEL and K562). In this approach, genomic DNA is sequentially cut at CCCGGG sites with the methylation-sensitive enzyme SmaI (blunt ends) and its methylation-tolerant neoschizomer XmaI (5'CCGG overhangs), creating different end sequences that represent methylation status of the CCCGGG sites. These end sequences are analyzed by next-generation sequencing, and thereafter the methylation status at individual CCCGGG sites across the genome can be determined.
Project description:Studies in yeast have demonstrated that signalling kinases with well known cytoplasmic functions have a surprisingly active role in the nucleus, where they are tethered to chromatin and modulate gene expression programs. Here we provide evidence for a novel function of the signal transduction kinase, protein kinase C-theta (PKC-0) that physically associates with the proximal regulatory regions of key inducible immune response genes in human T cells. Chromatin-anchored PKC-q forms hitherto undescribed nuclear complexes by interacting with active RNA polymerase II, the histone kinase MSK-1 and the adaptor molecule 14-3-3z. ChIP-on-Chip analysis reveals that PKC-0 binds directly to both the promoter and transcribed regions of genes, as well as to the promoters of microRNA genes implicated in cell migration and invasion. Moreover, enforced expression of these microRNAs is associated with heightened production of mRNAs encoding a distinct subset of inducible immune response genes. Collectively, these data suggest that in addition to its well known role as a cytoplasmic signalling kinase, PKC-0 controls immune gene expression within the nucleus of T cells by participating in chromatin-associated signalling complexes PKC-0 and Pol II ChIP DNA were pooled from five independent ChIP assay experiments that were first individually validated by real-time PCR. Pooled ChIP samples were subsequently amplified based on one round of the whole genome amplification method using the WGA2 kit (Sigma-Aldrich), as described previously (O'Geen, Hollenhorst, Dindot). An alternate random primed and linker-mediated PCR amplification protocol was compared with the WGA2 kit using quantitative real-time PCR, which generated similar yields of amplified material, but failed to preserve the degree of enrichment after the linker-mediated PCR amplification (data not shown). Labelling, hybridization and scanning were performed as described in the Mammalian ChIP-on-chip protocol (version 9.1; Agilent Technologies). Briefly, the control and PKC-0 or Pol II ChIP DNA were labelled with 5 ug cyanine-3 and 5 ug cyanine-5 (Invitrogen BioPrime CGH labeling kit), respectively. Samples were hybridised on each microarray slide for 40 h at 65°C. Agilent human promoter microarrays were utilised comprising of two slides per set defined to cover ~17,000 promoters of human transcripts from -5.5 to +2.5 Kb relative to transcriptional start site. The microarrays were scanned on an Agilent scanner (G2565BA) at 100% PMT gain. Two replicates of each ChIP-on-chip experiment were performed.