Many alkylating agents react with DNA to afford predominanfiy N7-adducts of deoxyguanosine (dG). The genotoxicity and cytotoxicity of agents that react primarily at N7-dG is often attributed to other less abundant DNA lesions. The overarching hypothesis of this PPG application is the cationic N7-dG adducts are converted into N5-substituted formamidopyrimidine (Fapy-dG) lesions in cells, and the latter lesions contribute significantly to the genotoxicity and cytotoxicity of alkylating agents. This Program Project interactively uses organic synthesis, bioanalytical chemistry, structural biology, enzymology, and molecular biology to elucidate the molecular details by which Fapy-dG adducts derived from endogenous and exogenous electrophiles and chemotherapeutic agents alter DNA replication and repair. Project 1 will utilize bioanalytical mass spectrometry, chemical synthesis, and enzymology to address this hypothesis. Efforts will focus on formamidopyrimidine (Fapy-dG) lesions derived from methylating agents such as temozolomide (MeFapy-dG), chlorooxirane (OxEt-Fapy-dG), thioTEPA (AE-Fapy-dG) and nitrogen mustards (NM-Fapy-dG), including interstrand cross-links (FapyG-NM-FapyG, and FapyG-NMG). Temozolomide, thioTEPA, and nitrogen mustards are clinically used chemotherapeutic agents and we hypothesize that the corresponding N5-substituted Fapy-dG lesion plays an important role in their mechanism of action.
The Specific Aims of Project 1 will establish the presence of N5-substituted Fapy-dG lesions in mammalian cells (Specific Aim 1), chemically synthesized oligonucleotides containing the desired Fapy-dG lesion in a site-specifically manner (Specific Aim 2), and determine the miscoding potential of the Fapy-dG lesion in vitro (Specific Aim 3). Our ability to site-specifically incorporate the Fapy-dG lesions into oligonucleotide is central to the research plans of Projects 1, 2 and 3. Project 1 will work closely with the DNA Synthesis Resource Core.

Public Health Relevance

Fapy lesions have been an understudied class of DNA adduct largely due to their complex chemistry. We propose to develop methods to understand the chemistry of these lesions, which will aid in their detection, preparation, and further study. The result will provide a better understanding of the role of DNA alkylating agents in human cancers and well as the mechanism of action of chemotherapuetic agents.

National Institute of Health (NIH)
National Cancer Institute (NCI)
Research Program Projects (P01)
Project #
Application #
Study Section
Special Emphasis Panel (ZCA1-RPRB-O)
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Vanderbilt University Medical Center
United States
Zip Code
Lin, Ying-Chih; Li, Liang; Makarova, Alena V et al. (2014) Molecular basis of aflatoxin-induced mutagenesis-role of the aflatoxin B1-formamidopyrimidine adduct. Carcinogenesis 35:1461-8
Lin, Ying-Chih; Li, Liang; Makarova, Alena V et al. (2014) Error-prone replication bypass of the primary aflatoxin B1 DNA adduct, AFB1-N7-Gua. J Biol Chem 289:18497-506
Minko, Irina G; Earley, Lauriel F; Larlee, Kimberly E et al. (2014) Pyrosequencing: applicability for studying DNA damage-induced mutagenesis. Environ Mol Mutagen 55:601-8
Christov, Plamen P; Son, Kyu-Jun; Rizzo, Carmelo J (2014) Synthesis and characterization of oligonucleotides containing a nitrogen mustard formamidopyrimidine monoadduct of deoxyguanosine. Chem Res Toxicol 27:1610-8
Singh, Vipender; Fedeles, Bogdan I; Li, Deyu et al. (2014) Mechanism of repair of acrolein- and malondialdehyde-derived exocyclic guanine adducts by the ?-ketoglutarate/Fe(II) dioxygenase AlkB. Chem Res Toxicol 27:1619-31
Gruppi, Francesca; Salyard, Tracy L Johnson; Rizzo, Carmelo J (2014) Synthesis of G-N (2)-(CH2)3-N (2)-G Trimethylene DNA interstrand cross-links. Curr Protoc Nucleic Acid Chem 5:5.14.1-5.14.15
Patra, Amritraj; Nagy, Leslie D; Zhang, Qianqian et al. (2014) Kinetics, structure, and mechanism of 8-Oxo-7,8-dihydro-2'-deoxyguanosine bypass by human DNA polymerase ?. J Biol Chem 289:16867-82
Balbo, Silvia; Turesky, Robert J; Villalta, Peter W (2014) DNA adductomics. Chem Res Toxicol 27:356-66
Petrova, Katya V; Millsap, Amy D; Stec, Donald F et al. (2014) Characterization of the deoxyguanosine-lysine cross-link of methylglyoxal. Chem Res Toxicol 27:1019-29
Gold, Barry; Stone, Michael P; Marky, Luis A (2014) Looking for Waldo: a potential thermodynamic signature to DNA damage. Acc Chem Res 47:1446-54

Showing the most recent 10 out of 16 publications