TDG
Description
The TDG (thymine DNA glycosylase) is a protein-coding gene located on chromosome 12.
TDG may refer to:
TDG (Thymine DNA glycosylase) is a DNA glycosylase that plays a critical role in active DNA demethylation. It specifically recognizes and binds 5-formylcytosine (5fC) and 5-carboxylcytosine (5caC) within CpG sites, excising them through base-excision repair (BER) to reinstate an unmethylated cytosine. It cannot remove 5-hydroxymethylcytosine (5hmC). Alternatively, TDG is implicated in DNA demethylation by mediating DNA glycosylase activity towards 5-hydroxymethyluracil (5hmU), generated through the deamination of 5hmC. Furthermore, TDG participates in DNA repair as a thymine-DNA glycosylase, rectifying G/T mispairs to G/C pairs. In higher eukaryotes, hydrolytic deamination of 5-methylcytosine to thymine results in the formation of G/T mismatches. However, its role in repairing canonical base damage is less prominent compared to its contribution to DNA demethylation. TDG is capable of hydrolyzing the carbon-nitrogen bond between the DNA's sugar-phosphate backbone and a mismatched thymine. Apart from G/T, it can remove thymine from C/T and T/T mispairs, with a preference for G/T over C/T and T/T. It exhibits no detectable activity on apyrimidinic sites and does not remove thymine from A/T pairs or single-stranded DNA. Additionally, TDG can remove uracil and 5-bromouracil from mispairs with guanine. {ECO:0000269|PubMed:21862836, ECO:0000269|PubMed:22327402, ECO:0000269|PubMed:22573813, ECO:0000269|PubMed:22962365, ECO:0000269|PubMed:8127859, ECO:0000269|PubMed:8407958, ECO:0000269|PubMed:8662714}
TDG is also known as hTDG.
Associated Diseases
- low grade glioma
- ovarian cancer
- esophageal cancer
- cor pulmonale
- hereditary breast ovarian cancer syndrome
- familial dysfibrinogenemia
- familial hypofibrinogenemia
- congenital factor X deficiency
- cancer
