Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Small RNA mediated DNA (cytosine-5) methyltransferase 1 inhibition leads to aberrant DNA methylation

ABSTRACT: Mammalian cells contain copious amounts of RNA including both coding and non-coding RNA (ncRNA). Generally the ncRNAs function to regulate gene expression at the transcriptional and post-transcriptional level. Among ncRNA, the long ncRNA and small ncRNA can affect histone modification, DNA methylation targeting and gene silencing. Here we show that endogenous DNA methyltransferase 1 (DNMT1) co-purifies with inhibitory ncRNAs. MicroRNAs (miRNAs) binds directly to DNMT1 with high affinity. The binding of miRNAs, such as miR-155, leads to inhibition of DNMT1 enzyme activity. Exogenous miR-155 in cells induces aberrant DNA methylation of the genome, resulting in hypomethylation of low to moderately methylated regions. And small shift of hypermethylation of previously hypomethylated region was also observed. Furthermore, hypomethylation led to activation of genes. Based on these observations, we propose that overexpression of specific miRNAs in human cancer may lead to aberrant DNA methylation and altered gene-expression.

ORGANISM(S): Homo sapiens

PROVIDER: GSE68027 | GEO | 2015/04/21

SECONDARY ACCESSION(S): PRJNA281584

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Small RNA mediated DNA (cytosine-5) methyltransferase 1 inhibition leads to aberrant DNA methylation

Project description:Mammalian cells contain copious amounts of RNA including both coding and non-coding RNA (ncRNA). Generally the ncRNAs function to regulate gene expression at the transcriptional and post-transcriptional level. Among ncRNA, the long ncRNA and small ncRNA can affect histone modification, DNA methylation targeting and gene silencing. Here we show that endogenous DNA methyltransferase 1 (DNMT1) co-purifies with inhibitory ncRNAs. MicroRNAs (miRNAs) binds directly to DNMT1 with high affinity. The binding of miRNAs, such as miR-155, leads to inhibition of DNMT1 enzyme activity. Exogenous miR-155 in cells induces aberrant DNA methylation of the genome, resulting in hypomethylation of low to moderately methylated regions. And small shift of hypermethylation of previously hypomethylated region was also observed. Furthermore, hypomethylation led to activation of genes. Based on these observations, we propose that overexpression of specific miRNAs in human cancer may lead to aberrant DNA methylation and altered gene-expression. Examine of the DNA methylation and mRNA profile of HCT 116 cells transfected by random 23-mer or miR-155 RNA

2015-04-21 | E-GEOD-68027 | biostudies-arrayexpress

S-adenosylhomocysteine hydrolase participates in DNA methylation inheritance

Project description:DNA (cytosine-5) methyltransferase 1 (DNMT1) is essential for mammalian development and maintenance of DNA methylation following DNA replication in cells. The DNA methylation process generates S-adenosyl-L-homocysteine, a strong inhibitor of DNMT1. Here we report that S-adenosylhomocysteine hydrolase (SAHH/AHCY), the only mammalian enzyme capable of hydrolyzing S-adenosyl-L-homocysteine binds to DNMT1 during DNA replication. SAHH activates DNMT1 in vitro and its overexpression in mammalian cells leads to hypermethylation of the genome, whereas its inhibition by adenosine periodate resulted in hypomethylation of the genome. Hypermethylation was consistent in both gene bodies and repetitive DNA elements leading to both down- and up-regulation of genes. Similarly, hypomethylation led to both up- and down-regulation of genes suggesting methylated regions influence gene expression either positively or negatively. Cells overexpressing SAHH specifically up-regulated metabolic pathway genes and down-regulated PPAR and MAPK signaling pathways genes. Therefore, we suggest that alteration of SAHH level in the cell leads to aberrant DNA methylation, altered metabolite levels and gene expression.

2018-06-06 | PXD006476 | Pride

A mutant DNMT1 enhances tumorigenicity with focal hypermethylation and global hypomethylation

Project description:Site-specific hypermethylation of tumor suppressor genes accompanied by genome-wide hypomethylation are epigenetic hallmarks of malignancy. However, molecular mechanisms that drive these linked changes in DNA methylation remain obscure. DNA methyltransferase 1 (DNMT1), the principle enzyme responsible for maintaining methylation patterns is commonly dysregulated in tumors. Replication foci targeting sequence (RFTS) is an N-terminal domain of DNMT1 that inhibits DNA-binding and catalytic activity, suggesting that RFTS deletion would result in gain of DNMT1 function. However, earlier data suggested that RFTS is required for DNMT1 activity. Here, we determined cellular consequences of RFTS deletion from DNMT1 in immortalized human bronchial epithelial cells. Compared to full-length DNMT1, ectopic expression of DNMT1- ?RFTS caused greater malignant transformation and enhanced promoter methylation that silenced DAPK and DUOX1 gene expression and increased intensity of promoter methylation across the genome. Strikingly, DNMT1-?RFTS also produced genomic hypomethylation and demethylation of Satellite 2 repeat sequences. Because deletion of RFTS is sufficient to induce focal hypermethylation and global hypomethylation in parallel, evidence suggests that the RFTS domain is a target responsible for epigenetic changes in cancer. DNA samples from HBEC3 cells transfected with vector control and HBEC3 cells with full-length and RFTS-deleted DNMT1 were assessed for genome-wide methylation using the microarray-based high resolution HpaII tiny fragment enriched by ligation-mediated PCR (HELP) assay.

2014-09-30 | E-GEOD-57829 | biostudies-arrayexpress

RFTS-deleted DNMT1 enhances tumorigenicity with focal hypermethylation and global hypomethylation

Project description:Site-specific hypermethylation of tumor suppressor genes accompanied by genome-wide hypomethylation are epigenetic hallmarks of malignancy. However, molecular mechanisms that drive these linked changes in DNA methylation remain obscure. DNA methyltransferase 1 (DNMT1), the principle enzyme responsible for maintaining methylation patterns is commonly dysregulated in tumors. Replication foci targeting sequence (RFTS) is an N-terminal domain of DNMT1 that inhibits DNA-binding and catalytic activity, suggesting that RFTS deletion would result in gain of DNMT1 function. However, earlier data suggested that RFTS is required for DNMT1 activity. Here, we determined cellular consequences of RFTS deletion from DNMT1 in immortalized human bronchial epithelial cells. Compared to full-length DNMT1, ectopic expression of DNMT1- ΔRFTS caused greater malignant transformation and enhanced promoter methylation that silenced DAPK and DUOX1 gene expression and increased intensity of promoter methylation across the genome. Strikingly, DNMT1-ΔRFTS also produced genomic hypomethylation and demethylation of Satellite 2 repeat sequences. Because deletion of RFTS is sufficient to induce focal hypermethylation and global hypomethylation in parallel, evidence suggests that the RFTS domain is a target responsible for epigenetic changes in cancer.

2014-09-30 | GSE57829 | GEO

G-quadruplex structures moulds the DNA methylome

Project description:Control of DNA methylation level is critical for gene regulation, and the factors that govern hypomethylation at CpG islands (CGIs) are still being uncovered. Here, we provide evidence that G-quadruplex (G4) DNA secondary structures are genomic features that influence methylation at CGIs. We show that the presence of G4 structure is tightly associated with CGI hypomethylation. Surprisingly, we find that these G4 sites are enriched for DNA methyltransferase 1 (DNMT1) occupancy, which is consistent with our biophysical observations that DNMT1 exhibits higher binding affinity for G4s as compared to duplex, hemi-methylated or single-stranded DNA. The biochemical assays also show that the G4 structure itself, rather than sequence, inhibits DNMT1 enzymatic activity. Based on these data, we propose that G4 formation sequesters DNMT1 thereby protecting certain CGIs from methylation and inhibiting local methylation.

2018-07-16 | GSE107690 | GEO

DNMT1 IP-MS alalysis to identify ubiquitin-dependent interacting partners

Project description:Stable inheritance of DNA methylation is critical for maintaining the differentiated phenotypes in multicellular organisms. However, the molecular basis ensuring high fidelity of maintenance DNA methylation is largely unknown. Here, we demonstrate that two distinct modes of DNMT1 recruitment, one is DNA replication-coupled and the other is uncoupled mechanism, regulate the stable inheritance of DNA methylation. PCNA-associated factor 15 (PAF15) represents a primary target of UHRF1 and undergoes dual mono-ubiquitylation (PAF15Ub2) on chromatin. PAF15Ub2 specifically interacts with DNMT1 and controls the recruitment of DNMT1 in a DNA replication-coupled manner. Thus, loss of PAF15Ub2 results in impaired DNA methylation at sites replicating during early S phase. In contrast, outside of S phase or when PAF15 ubiquitylation is perturbed, UHRF1 ubiquitylates histone H3 to promote DNMT1 recruitment. Together, we identify replication-coupled and uncoupled mechanisms of maintenance DNA methylation, both of which collaboratively ensure the stable DNA methylation.

2020-02-25 | PXD015282 | Pride

Binding of 14-3-3 reader proteins to phosphorylated DNMT1 facilitates aberrant DNA methylation and gene expression

Project description:Mammalian DNA (cytosine-5) methyltransferase 1 (DNMT1) is essential for maintenance methylation. Phosphorylation of Ser143 (pSer143) stabilizes DNMT1 during DNA replication. Here, we show 14-3-3 is a reader protein of DNMT1pSer143. In mammalian cells 14-3-3 colocalizes and binds DNMT1pSer143 post-DNA replication. The level of DNMT1pSer143 increased with overexpression of 14-3-3 and decreased by its depletion. Binding of 14-3-3 proteins with DNMT1pSer143 resulted in inhibition of DNA methylation activity in vitro. In addition, overexpression of 14-3-3 in NIH3T3 cells led to decrease in DNMT1 specific activity and was rescued by transfection of DNMT1. Decrease in DNMT1 specific activity led to hypomethylation of the genome. Genes representing cell migration, mobility, proliferation and focal adhesion pathway were hypomethylated and overexpressed. Furthermore, 14-3-3 overexpression also resulted in enhanced cell invasion. Therefore, we suggest that 14-3-3 is a crucial reader of DNMT1pSer143 that regulates DNMT1 level, DNA methylation and altered gene expression that contributes to cell invasion. Examine of the DNA methylation and RNA expression profiles of stable NIH3T3 clones overexressing the 14-3-3ε homologue

2015-09-10 | E-GEOD-72860 | biostudies-arrayexpress

DNA methylation, through DNMT1, has an essential role in the development of gastrointestinal smooth muscle cells and disease [RNA-Seq]

Project description:DNA methylation is a key epigenetic modification that can regulate gene expression. Genomic DNA hypomethylation is commonly found in many gastrointestinal (GI) diseases. Dysregulated gene expression in GI smooth muscle cells (GI-SMC) can lead to motility disorders. However, the consequences of genomic DNA hypomethylation within GI-SMC are still elusive. Utilizing a Cre-lox murine model, we have generated SMC-restricted DNA methyltransferase 1 (Dnmt1) knockout (KO) mice and analyzed the effects of Dnmt1 deficiency. Dnmt1-KO pups are born smaller than their wild type littermates, have shortened GI tracts, lose peristaltic movement due to loss of the tunica muscularis in their intestine, causing massive intestinal dilation, and death around post-natal day 21. Within smooth muscle tissue, significant CpG hypomethylation occurs across the genome at promoters, introns and exons. Additionally, there is a marked loss of differentiated SMC markers (Srf, Myh11, miR-133, miR-143/145), an increase in pro-apoptotic markers (Nr4a1, Gadd45g), loss of cellular connectivity, and an accumulation of coated vesicles within SMC. Interestingly, we observed consistent abnormal expression patterns of enzymes involved in DNA methylation between both ¬Dnmt1-KO mice and diseased human GI tissue. These data demonstrate that DNA hypomethylation in embryonic SMC, via congenital Dnmt1 deficiency, contributes to massive dysregulation of gene expression and is lethal to GI-SMC. These results suggest that Dnmt1 has a necessary role in the embryonic, primary development process of SMC with consistent patterns being found in human GI diseased tissue.

2018-02-13 | GSE109272 | GEO

DNA methylation, through DNMT1, has an essential role in the development of gastrointestinal smooth muscle cells and disease [miRNA-Seq]

2018-02-13 | GSE109273 | GEO

DNA methylation, through DNMT1, has an essential role in the development of gastrointestinal smooth muscle cells and disease (BiSulfite-seq)

2018-02-13 | GSE109641 | GEO