Both GO (7,8-dihydro-8-oxoguanine) and hoU (5-hydroxyuracil) are highly mutagenic because DNA polymerase frequently misincorporates adenine opposite these damaged bases. In Escherichia coli, MutY DNA glycosylase can remove misincorporated adenine opposite G or GO on the template strand during DNA replication. MutY remains bound to the product that contains an AP (apurinic/apyrimidinic) site. Endo VIII (endonuclease VIII) can remove oxidized pyrimidine and weakly remove GO by its DNA glycosylase and β/δ-elimination activities. In the present paper, we demonstrate that Endo VIII can promote MutY dissociation from AP/G, but not from AP/GO, and can promote β/δ-elimination on the products of MutY. MutY interacts physically with Endo VIII through its C-terminal domain. MutY has a moderate affinity for DNA containing a hoU/A mismatch, which is a substrate of Endo VIII. MutY competes with Endo VIII and inhibits Endo VIII activity on DNA that contains a hoU/A mismatch. Moreover, MutY has a weak adenine glycosylase activity on hoU/A mismatches. These results suggest that MutY may have some role in reducing the mutagenic effects of hoU.
Skip Nav Destination
Research Article| December 12 2005
Physical and functional interactions between Escherichia coli MutY and endonuclease VIII
A-Lien Lu 1
1Department of Biochemistry and Molecular Biology and Greenebaum Cancer Center, School of Medicine, University of Maryland, Baltimore, MD 21201, U.S.A.
1To whom correspondence should be addressed (email firstname.lastname@example.org).
Search for other works by this author on:
- Views Icon Views
- Share Icon Share
A-Lien Lu, Chih-Yung Lee, Lina Li, Xianghong Li; Physical and functional interactions between Escherichia coli MutY and endonuclease VIII. Biochem J 1 January 2006; 393 (1): 381–387. doi: https://doi.org/10.1042/BJ20051133
Download citation file:
Don't already have an account? Register
Get Access To This Article
Buy This Article