Uracil-DNA glycosylase family 1 (IPR002043)

Short name: UDG_fam1

Overlapping homologous superfamilies

Family relationships



Uracil-DNA glycosylase EC:3.2.2 (UDG, UNG) [PMID: 3052275] is a DNA repair enzyme that excises uracil residues from DNA by cleaving the N-glycosylic bond. Uracil in DNA can arise as a result of mis-incorporation of dUMP residues by DNA polymerase or deamination of cytosine. UDGs were classified into 4 families [PMID: 11223884, PMID: 10946227].

Family 1 enzymes are active against uracil in both ssDNA and dsDNA, and recognize uracil explicitly in an extrahelical conformation via a combination of protein and bound-water interactions [PMID: 10946227]. Family 1 enzymes are present in Eubacteria, Eukarya and in some eukaryotic viruses. The sequence of uracil-DNA glycosylases is extremely well conserved [PMID: 2555154] in bacteria and eukaryotes as well as in herpes viruses. More distantly related uracil-DNA glycosylases are also found in poxviruses [PMID: 8389453]. In eukaryotic cells, UNG activity is found in both the nucleus and the mitochondria. Human nuclear UNG2 and mitochondrial UNG1 are both encoded by the UNG gene [PMID: 8332455, PMID: 19008197]. The N-terminal 77 amino acids of UNG1 seem to be required for mitochondrial localisation [PMID: 8332455].

GO terms

Biological Process

GO:0006281 DNA repair
GO:0006284 base-excision repair

Molecular Function

GO:0004844 uracil DNA N-glycosylase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.