cd10032

MUG-like Uracil-DNA glycosylase enzyme family; MUG-like subfamily of Uracil-DNA glycosylase superfamily: Uracil-DNA glycosylases (UDG) catalyze the removal of uracil from DNA to initiate DNA base excision repair pathway. Uracil in DNA can arise as a result of mis-incorporation of dUMP residues by DNA polymerase or deamination of cytosine. Uracil mispaired with guanine in DNA is one of the major pro-mutagenic events, causing G:C->A:T mutations. Thus, UDG is an essential enzyme for maintaining the integrity of genetic information. The members of this family show closest sequence homology to that of G:T/U mismatch specific DNA glcosylase (MUG, Family 2 UDG). MUG catalyzes the removal of thymine or uracil bases mispaired with guanine through the hydrolysis of their N-glycosidic bond, generating abasic sites in DNA to initiate base excision repair pathway. MUGs are dsDNA specific excision repair enzyme. They explicitly recognize the widowed guanine on the complementary strand rather than the extrahelical scissile pyrimidine.