Project description:TET1 maintains hypomethylation at bivalent promoters through its catalytic activity in embryonic stem cells (ESCs). However, whether and how TET1 exerts catalytic activity-independent functions in regulating bivalent genes is not well understood. Therefore, we mapped the TET1 interactome in mouse ESCs using a SILAC IP-MS proteomics approach.

2022-06-10 | PXD033587 | Pride

Tet1 and hydroxymethylcytosine in transcription and DNA methylation fidelity (Affymetrix gene expression data)

Project description:Enzymes catalyzing the methylation of the 5-position of cytosine (mC) have essential roles in regulating gene expression, genome stability, and maintaining cellular identity. Recently Tet1, which is highly expressed in embryonic stem (ES) cells, was found to oxidize the methyl group of mC converting it to 5-hydroxymethyl cytosine (hmC)3. Here, we present the genome-wide mapping of Tet1 and hmC in mouse ES cells. We show that Tet1 binds throughout the genome with the majority of binding sites located at transcription start sites (TSSs) and within genes. Similar to Tet1 and mC, also hmC is found throughout the genome and in particular in gene bodies. However, in contrast to mC, hmC is enriched at TSSs. Tet1 and hmC are associated with genes critical for the control of development and differentiation, which become methylated during differentiation. Surprisingly our results also suggest that Tet1 has a role in transcriptional repression. We show that Tet1 binds to a significant proportion of target genes that are positive for the Polycomb repressive histone mark H3K27me3, and that downregulation of Tet1 also leads to increased expression of a group of Tet1 target genes. In agreement with a potential repressive function, we show that Tet1 associates with the Sin3A co-repressor complex, which also co-localises with Tet1 throughout the genome. We propose that Tet1 fulfils dual functions in transcriptional regulation, where it fine-tunes DNA methylation and associates with the Sin3A co-repressor complex to prevent transcriptional activation. [GSM611209-GSM611217] Control (shScr) or two different Tet1 knockdown (shTet1#4 or shTet1#5) mouse ES cells were used. Each experiment was performed in triplicates. [GSM675884-GSM675889] Control (shScr) or Sin3A knockdown (shSin3A) mouse ES cells were used.Each experiment was performed in triplicates.

2011-04-13 | E-GEOD-24842 | biostudies-arrayexpress

Lin28A binds active promoters and recruits Tet1 to regulate gene expression

Project description:Lin28, a well-known RNA-binding protein, regulates diverse cellular properties. All physiological functions of Lin28A characterized so far have been attributed to its repression of let-7 miRNA biogenesis or modulation of the mRNA translational efficiency. Here we show that Lin28A directly binds to a consensus DNA sequence in vitro and in mouse embryonic stem cells in vivo. ChIP-seq and RNA-seq reveal the enrichment of Lin28A binding around transcription start sites, and a positive correlation between its genomic occupancy and expression of many associated genes. Mechanistically, Lin28A recruits 5-methylcytosine-dioxygenase Tet1 to genomic binding sites to orchestrate 5-methylcytosine and 5-hydroxymethylcytosine dynamics. Either Lin28A or Tet1 knockdown leads to dysregulated DNA methylation and expression of common target genes. These results reveal a surprising role for Lin28A in transcriptional regulation via epigenetic DNA modifications and provide a new framework for understanding mechanisms underlying versatile functions of Lin28A in mammalian systems. Examine the DNA binding ability of Lin28 and its roles in regulating gene expression by coordinating with Tet1

2015-12-07 | E-GEOD-74254 | biostudies-arrayexpress

Tet1 and hydroxymethylcytosine in transcription and DNA methylation fidelity (Affymetrix gene expression data)

2011-04-13 | GSE24842 | GEO

5-hydroxymethylcytosine: the sixth DNA base

Project description:We performed a meta analysis of publicly available TET1, 5mC, 5hmC and genome wide bisulfite profiling data mostly from mouse embryonic stem cells (ESC). Genome wide chromatin immunoprecipitation combined with deep sequencing (ChIP-seq) has revealed binding of the TET1 protein at CpG-island (CGI) promoters and at bivalent promoters. We show that TET1 also coincides with DNAseI hypersensitive sites (HS). Presence of TET1 at these THREE locations suggests that it may play a dual role: an active role at CpG-islands and DNAseI hypersensitive sites and a repressive role at bivalent loci. In line with the presence of TET1, significant enrichment of 5hmC but not 5mC is detected at bivalent promoters and DNaseI HS. Surprisingly, 5hmC is not detected or present at very low levels at CGI promoters notwithstanding the presence of TET1 at these loci. Our meta analysis suggest that asymmetric methylation is present at CA- and CT-repeats in the genome of some human ESC. Examination of the distribution of 5-methylcytosine and 5-hydroxymethylcytosine in the genome of mouse embryonic stem cells.

2011-11-24 | E-GEOD-31343 | biostudies-arrayexpress

Mus musculus

Project description:Genome-wide analysis of 5-hydroxymethylcytosine distribution reveals its dual function in transcriptional regulation in mouse embryonic stem cells

| PRJNA138263 | ENA

Mus musculus

Project description:Zfp281 Functions as a Transcriptional Repressor for Pluripotency of Mouse Embryonic Stem Cells

| PRJNA143789 | ENA