Normal cells replicate their genomes with high fidelity (approximately 10-10 mutations/nt/replication cycle). This is achieved through the combined actions of polymerase base selectivity, exonucleolytic proofreading (exo), mismatch correction and DNA damage repair. We recently created """"""""knock-in"""""""" mice with an inactivating point mutation (Pold1D400A) in the 3'-->5' exonucleolytic proofreading domain of DNA polymerase d (Pol d) and showed that homozygous mutants develop a unique spectrum of early-onset epithelial tumors (skin and lung, but not intestine). Here we propose to use these novel Pol delta exo-mice and derivative cell lines to characterize the role of Pol delta proofreading in the maintenance of genetic stability and avoidance of cancer in mammals.
The specific aims are: 1. Characterize the mutator phenotype of Pol delta exo-cells and mice. To ascertain the extent and nature of the mutator phenotype conferred by loss of Pol delta proofreading, we will determine rates, frequencies and spectra of spontaneous mutations arising in Poldelta1D400A cells in culture and tissues in vivo. 2. Examine cooperativity of Pol delta proofreading with mismatch repair (MMR). Mice and cells carrying combinations of Pol delta proofreading and MMR alleles will be studied to assess how these error correction systems cooperate in mammals at the phenotypic level (survival, mutator and cancer phenotypes). Together, these studies will significantly contribute to our understanding of mutator phenotypes in cancer and will characterize the contribution of Pol delta proofreading to mutation- and cancer-avoidance in mammals.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA098243-02
Application #
6881590
Study Section
Cancer Etiology Study Section (CE)
Program Officer
Okano, Paul
Project Start
2004-04-06
Project End
2008-03-31
Budget Start
2005-04-01
Budget End
2006-03-31
Support Year
2
Fiscal Year
2005
Total Cost
$248,624
Indirect Cost
Name
University of Washington
Department
Pathology
Type
Schools of Medicine
DUNS #
605799469
City
Seattle
State
WA
Country
United States
Zip Code
98195
Williams, Lindsey N; Herr, Alan J; Preston, Bradley D (2013) Emergence of DNA polymerase ? antimutators that escape error-induced extinction in yeast. Genetics 193:751-70
Herr, Alan J; Ogawa, Masanori; Lawrence, Nicole A et al. (2011) Mutator suppression and escape from replication error-induced extinction in yeast. PLoS Genet 7:e1002282
Wright, Jocelyn H; Modjeski, Kristina L; Bielas, Jason H et al. (2011) A random mutation capture assay to detect genomic point mutations in mouse tissue. Nucleic Acids Res 39:e73
Herr, Alan J; Williams, Lindsey N; Preston, Bradley D (2011) Antimutator variants of DNA polymerases. Crit Rev Biochem Mol Biol 46:548-70
Preston, Bradley D; Albertson, Tina M; Herr, Alan J (2010) DNA replication fidelity and cancer. Semin Cancer Biol 20:281-93
Treuting, Piper M; Albertson, Tina M; Preston, Bradley D (2010) Case series: acute tumor lysis syndrome in mutator mice with disseminated lymphoblastic lymphoma. Toxicol Pathol 38:476-85
Albertson, Tina M; Ogawa, Masanori; Bugni, James M et al. (2009) DNA polymerase epsilon and delta proofreading suppress discrete mutator and cancer phenotypes in mice. Proc Natl Acad Sci U S A 106:17101-4
Venkatesan, Ranga N; Hsu, Jessica J; Lawrence, Nicole A et al. (2006) Mutator phenotypes caused by substitution at a conserved motif A residue in eukaryotic DNA polymerase delta. J Biol Chem 281:4486-94