OF WORK: Our studies of mammalian DNA polymerase beta have pioneered the use of a coordinated approach of structural studies (x-ray crystallography, NMR, and spectroscopy), biochemical studies, and mammalian genetic studies to understand genomic stability in mammalian cells. This approach has allowed us to establish the cellular role(s) of DNA polymerase beta in mammalian base excision repair. And, the approach has allowed us to establish a solid framework for future studies of individual amino acid residues in this enzyme in such important endpoints as cellular response to genotoxicants, the rate of DNA repair, coordination of DNA repair with cellular checkpoint control and also with apoptosis signalling, coordination of deoxyribose phosphate removal (lyase activity) with DNA synthesis, the fidelity of DNA synthesis, the fidelity of overall DNA base excision repair, and DNA lesion bypass. Rational drug design, targeting one or more of these features will allow us to strategically regulate base excision repair with DNA polymerase beta specific drugs. Such agents may be useful in cancer chemotherapy and in helping us to better understand the role of DNA repair in oncogenesis and other chronic diseases. Detailed structure-function relationship studies of other base excision repair (BER) enzymes and accessory factors, such as FEN-1, PARP-1, XRCC1, DNA ligases I and III, AP endonuclease, and the various DNA glycosylases, will be undertaken in the future. Development of specific inhibitors or other modulators for these enzymes will allow us to strategically de-regulate base excision repair in cells. This will have implications for chemotherapy and for understanding the role of DNA repair in preventing disease after exposure to environmental toxicants.

Project Start
Project End
Budget Start
Budget End
Support Year
17
Fiscal Year
2013
Total Cost
$2,106,781
Indirect Cost
City
State
Country
Zip Code
Cilli, Piera; Ventura, Ilenia; Minoprio, Anna et al. (2016) Oxidized dNTPs and the OGG1 and MUTYH DNA glycosylases combine to induce CAG/CTG repeat instability. Nucleic Acids Res 44:5190-203
Kim, Taejin; Freudenthal, Bret D; Beard, William A et al. (2016) Insertion of oxidized nucleotide triggers rapid DNA polymerase opening. Nucleic Acids Res 44:4409-24
Batra, Vinod K; Beard, William A; Pedersen, Lars C et al. (2016) Structures of DNA Polymerase Mispaired DNA Termini Transitioning to Pre-catalytic Complexes Support an Induced-Fit Fidelity Mechanism. Structure 24:1863-1875
Freudenthal, Bret D; Beard, William A; Cuneo, Matthew J et al. (2015) Capturing snapshots of APE1 processing DNA damage. Nat Struct Mol Biol 22:924-31
Freudenthal, Bret D; Beard, William A; Wilson, Samuel H (2015) New structural snapshots provide molecular insights into the mechanism of high fidelity DNA synthesis. DNA Repair (Amst) 32:3-9
Kadina, Anastasia P; Kashemirov, Boris A; Oertell, Keriann et al. (2015) Two Scaffolds from Two Flips: (α,β)/(β,γ) CH2/NH "Met-Im" Analogues of dTTP. Org Lett 17:2586-9
Perera, Lalith; Freudenthal, Bret D; Beard, William A et al. (2015) Requirement for transient metal ions revealed through computational analysis for DNA polymerase going in reverse. Proc Natl Acad Sci U S A 112:E5228-36
Çağlayan, Melike; Horton, Julie K; Wilson, Samuel H (2015) Enzymatic Activity Assays for Base Excision Repair Enzymes in Cell Extracts from Vertebrate Cells. Bio Protoc 5:
Gassman, Natalie R; Coskun, Erdem; Stefanick, Donna F et al. (2015) Bisphenol a promotes cell survival following oxidative DNA damage in mouse fibroblasts. PLoS One 10:e0118819
Freudenthal, Bret D; Beard, William A; Perera, Lalith et al. (2015) Uncovering the polymerase-induced cytotoxicity of an oxidized nucleotide. Nature 517:635-9

Showing the most recent 10 out of 79 publications