A variety of mutagenic/carcinogenic agents induce the formation of ring-opened, formamidopyrimidine dG and dA lesions, e.g., via ROS either spontaneously or with ionizing radiation. In spite of their potential importance, little is known about the biological significance of Fapy adducts. The principal investigator has developed some novel chemical strategies for preparing site-specifically modified oligonucleotides containing lesions that are sensitive to base deprotection, including Fapy(via Pd(0) deprotection and photolytic release from solid supports). Preliminary studies with another lesion (5OH-T) are described. Proposed are syntheses of oligos containing dA-Fapy and dG-Fapy, along with a variety of derivatives, which will be investigated for replication (in vitro polymerase bypass) (#1), as substrates for Fapy glycosylase (#2), as inhibitors of nucleases (#3), in thermodynamic studies (#4), and in structural analysis by NMR (#5). (1)5,6-Dihydro-5-hydroxythymine (5OH-T) was prepared by the principal investigator's newly developed, novel synthetic procedure. (2) Steady state polymerase bypass was investigated (Goodman approach), and kinetic parameters determined for incorporation of bases opposite the lesions and for bypass. 5OH-T appears to be a blocking but non-mutagenic lesion (e.g.) with Kf(exo-).

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA074954-02
Application #
2748945
Study Section
Chemical Pathology Study Section (CPA)
Program Officer
Pelroy, Richard
Project Start
1997-09-10
Project End
2001-07-31
Budget Start
1998-08-01
Budget End
1999-07-31
Support Year
2
Fiscal Year
1998
Total Cost
Indirect Cost
Name
Colorado State University-Fort Collins
Department
Chemistry
Type
Schools of Arts and Sciences
DUNS #
112617480
City
Fort Collins
State
CO
Country
United States
Zip Code
80523
Pande, Paritosh; Haraguchi, Kazuhiro; Jiang, Yu-Lin et al. (2015) Unlike catalyzing error-free bypass of 8-oxodGuo, DNA polymerase ? is responsible for a significant part of Fapy·dG-induced G ? T mutations in human cells. Biochemistry 54:1859-62
Zhang, Bintian; Guo, Liang-Hong; Greenberg, Marc M (2012) Quantification of 8-oxodGuo lesions in double-stranded DNA using a photoelectrochemical DNA sensor. Anal Chem 84:6048-53
Greenberg, Marc M (2012) The formamidopyrimidines: purine lesions formed in competition with 8-oxopurines from oxidative stress. Acc Chem Res 45:588-97
Weledji, Yvonne N; Wiederholt, Carissa J; Delaney, Michael O et al. (2008) DNA polymerase bypass in vitro and in E. coli of a C-nucleotide analogue of Fapy-dG. Bioorg Med Chem 16:4029-34
Krishnamurthy, Nirmala; Haraguchi, Kazuhiro; Greenberg, Marc M et al. (2008) Efficient removal of formamidopyrimidines by 8-oxoguanine glycosylases. Biochemistry 47:1043-50
Xue, Liang; Greenberg, Marc M (2007) Facile quantification of lesions derived from 2'-deoxyguanosine in DNA. J Am Chem Soc 129:7010-1
Patro, Jennifer N; Wiederholt, Carissa J; Jiang, Yu Lin et al. (2007) Studies on the replication of the ring opened formamidopyrimidine, Fapy.dG in Escherichia coli. Biochemistry 46:10202-12
Das, Aditi; Boldogh, Istvan; Lee, Jae Wan et al. (2007) The human Werner syndrome protein stimulates repair of oxidative DNA base damage by the DNA glycosylase NEIL1. J Biol Chem 282:26591-602
Kalam, M Abul; Haraguchi, Kazuhiro; Chandani, Sushil et al. (2006) Genetic effects of oxidative DNA damages: comparative mutagenesis of the imidazole ring-opened formamidopyrimidines (Fapy lesions) and 8-oxo-purines in simian kidney cells. Nucleic Acids Res 34:2305-15
Imoto, Shuhei; Patro, Jennifer N; Jiang, Yu Lin et al. (2006) Synthesis, DNA polymerase incorporation, and enzymatic phosphate hydrolysis of formamidopyrimidine nucleoside triphosphates. J Am Chem Soc 128:14606-11

Showing the most recent 10 out of 30 publications