Search results for "Thymine DNA Glycosylase"
showing 3 items of 3 documents
Functional impacts of 5-hydroxymethylcytosine, 5-formylcytosine, and 5-carboxycytosine at a single hemi-modified CpG dinucleotide in a gene promoter
2017
Abstract Enzymatic oxidation of 5-methylcytosine (5-mC) in the CpG dinucleotides to 5-hydroxymethylcytosine (5-hmC), 5-formylcytosine (5-fC) and 5-carboxycytosine (5-caC) has central role in the process of active DNA demethylation and epigenetic reprogramming in mammals. However, it is not known whether the 5-mC oxidation products have autonomous epigenetic or regulatory functions in the genome. We used an artificial upstream promoter constituted of one cAMP response element (CRE) to measure the impact of 5-mC in a hemi-methylated CpG on the promoter activity and further explored the consequences of 5-hmC, 5-fC, and 5-caC in the same system. All modifications induced mild impairment of the …
Excision of Uracil from Transcribed DNA Negatively Affects Gene Expression
2014
Uracil is an unavoidable aberrant base in DNA, the repair of which takes place by a highly efficient base excision repair mechanism. The removal of uracil from the genome requires a succession of intermediate products, including an abasic site and a single strand break, before the original DNA structure can be reconstituted. These repair intermediates are harmful for DNA replication and also interfere with transcription under cell-free conditions. However, their relevance for cellular transcription has not been proved. Here we investigated the influence of uracil incorporated into a reporter vector on gene expression in human cells. The expression constructs contained a single uracil opposi…
Stable Oxidative Cytosine Modifications Accumulate in Cardiac Mesenchymal Cells From Type2 Diabetes Patients
2018
Rationale: Human cardiac mesenchymal cells (CMSCs) are a therapeutically relevant primary cell population. Diabetes mellitus compromises CMSC function as consequence of metabolic alterations and incorporation of stable epigenetic changes. Objective: To investigate the role of α-ketoglutarate (αKG) in the epimetabolic control of DNA demethylation in CMSCs. Methods and Results: Quantitative global analysis, methylated and hydroxymethylated DNA sequencing, and gene-specific GC methylation detection revealed an accumulation of 5-methylcytosine, 5-hydroxymethylcytosine, and 5-formylcytosine in the genomic DNA of human CMSCs isolated from diabetic donors. Whole heart genomic DNA analysis reveale…