Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7334
pubmed:dateCreated
2011-2-18
pubmed:databankReference
pubmed:abstractText
Thymine DNA glycosylase (TDG) is a member of the uracil DNA glycosylase (UDG) superfamily of DNA repair enzymes. Owing to its ability to excise thymine when mispaired with guanine, it was proposed to act against the mutability of 5-methylcytosine (5-mC) deamination in mammalian DNA. However, TDG was also found to interact with transcription factors, histone acetyltransferases and de novo DNA methyltransferases, and it has been associated with DNA demethylation in gene promoters following activation of transcription, altogether implicating an engagement in gene regulation rather than DNA repair. Here we use a mouse genetic approach to determine the biological function of this multifaceted DNA repair enzyme. We find that, unlike other DNA glycosylases, TDG is essential for embryonic development, and that this phenotype is associated with epigenetic aberrations affecting the expression of developmental genes. Fibroblasts derived from Tdg null embryos (mouse embryonic fibroblasts, MEFs) show impaired gene regulation, coincident with imbalanced histone modification and CpG methylation at promoters of affected genes. TDG associates with the promoters of such genes both in fibroblasts and in embryonic stem cells (ESCs), but epigenetic aberrations only appear upon cell lineage commitment. We show that TDG contributes to the maintenance of active and bivalent chromatin throughout cell differentiation, facilitating a proper assembly of chromatin-modifying complexes and initiating base excision repair to counter aberrant de novo methylation. We thus conclude that TDG-dependent DNA repair has evolved to provide epigenetic stability in lineage committed cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1476-4687
pubmed:author
pubmed:issnType
Electronic
pubmed:day
17
pubmed:volume
470
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
419-23
pubmed:meshHeading
pubmed-meshheading:21278727-Animals, pubmed-meshheading:21278727-Cell Differentiation, pubmed-meshheading:21278727-Cell Lineage, pubmed-meshheading:21278727-Chromatin, pubmed-meshheading:21278727-CpG Islands, pubmed-meshheading:21278727-DNA Methylation, pubmed-meshheading:21278727-DNA Repair, pubmed-meshheading:21278727-Embryo, Mammalian, pubmed-meshheading:21278727-Embryonic Development, pubmed-meshheading:21278727-Epigenesis, Genetic, pubmed-meshheading:21278727-Fibroblasts, pubmed-meshheading:21278727-Gene Deletion, pubmed-meshheading:21278727-Gene Expression Regulation, Developmental, pubmed-meshheading:21278727-Genes, Essential, pubmed-meshheading:21278727-Genes, Lethal, pubmed-meshheading:21278727-Histones, pubmed-meshheading:21278727-Mice, pubmed-meshheading:21278727-Mice, Knockout, pubmed-meshheading:21278727-Phenotype, pubmed-meshheading:21278727-Promoter Regions, Genetic, pubmed-meshheading:21278727-Thymine DNA Glycosylase
pubmed:year
2011
pubmed:articleTitle
Embryonic lethal phenotype reveals a function of TDG in maintaining epigenetic stability.
pubmed:affiliation
Department of Biomedicine, Institute of Biochemistry and Genetics, University of Basel, 4048 Basel, Switzerland.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't