The survival of all organisms depends on the faithful transmission of DNA from one cell to its daughter cell. Cells respond to DNA damage by arresting the cell cycle and inducing the transcription of DNA repair genes. The Crt 1 protein has been identified as a key regulator of DNA damage-induced transcription of the genes encoding ribonucleotide reductase (RNR). The broad, long-term objective of this research program is to use modem methods in molecular genetics and biochemistry to understand the mechanisms underlying cellular response to DNA damage. The focus of this project is on the functional studies of Crtl, and to relate this understanding to the regulation of DNA damage response. This proposal also seeks to investigate CRT1-independent mechanism(s) involved in DNA damage-induced transcription.
Specific aims of the proposed research are: (1) To characterize the regulation of Crt 1 activities by the upstream checkpoint kinases in order to understand the negative feedback mechanism of the CRTl-mediated DNA damage response. (2) To characterize the interactions between Crtl and the general repressor complex Ssn6/Tup 1 in response to DNA damage in order to understand how the DNA damage checkpoint controls the switch from the repressed state to the induced state. (3) To determine CRTl-independent mechanism(s) involved in the DNA damage-induced transcription of the RNR genes with the ultimate aim of understanding the interplay among different regulatory pathways controlled by the DNA damage checkpoint. Failure of DNA damage response results in genomic instability and cancer predisposition. As a result, this research will contribute to an increased understanding of the complex biology of DNA damage and repair. These studies will also be critical in guiding our efforts to target the DNA damage response process for cancer diagnosis, prevention, and treatment.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA095207-05
Application #
7192534
Study Section
Radiation Study Section (RAD)
Program Officer
Pelroy, Richard
Project Start
2003-03-01
Project End
2010-02-28
Budget Start
2007-03-01
Budget End
2010-02-28
Support Year
5
Fiscal Year
2007
Total Cost
$277,438
Indirect Cost
Name
University of Colorado Denver
Department
Biochemistry
Type
Schools of Medicine
DUNS #
041096314
City
Aurora
State
CO
Country
United States
Zip Code
80045
Wu, Xiaorong; Liu, Lili; Huang, Mingxia (2011) Analysis of changes in protein level and subcellular localization during cell cycle progression using the budding yeast Saccharomyces cerevisiae. Methods Mol Biol 782:47-57
Zhang, Zhen; Yang, Kui; Chen, Chin-Chuan et al. (2007) Role of the C terminus of the ribonucleotide reductase large subunit in enzyme regeneration and its inhibition by Sml1. Proc Natl Acad Sci U S A 104:2217-22
An, Xiuxiang; Zhang, Zhen; Yang, Kui et al. (2006) Cotransport of the heterodimeric small subunit of the Saccharomyces cerevisiae ribonucleotide reductase between the nucleus and the cytoplasm. Genetics 173:63-73
Ortigosa, Allison D; Hristova, Daniela; Perlstein, Deborah L et al. (2006) Determination of the in vivo stoichiometry of tyrosyl radical per betabeta' in Saccharomyces cerevisiae ribonucleotide reductase. Biochemistry 45:12282-94
Zhang, Zhen; An, Xiuxiang; Yang, Kui et al. (2006) Nuclear localization of the Saccharomyces cerevisiae ribonucleotide reductase small subunit requires a karyopherin and a WD40 repeat protein. Proc Natl Acad Sci U S A 103:1422-7
Perlstein, Deborah L; Ge, Jie; Ortigosa, Allison D et al. (2005) The active form of the Saccharomyces cerevisiae ribonucleotide reductase small subunit is a heterodimer in vitro and in vivo. Biochemistry 44:15366-77
Yao, Ruojin; Zhang, Zhen; An, Xiuxiang et al. (2003) Subcellular localization of yeast ribonucleotide reductase regulated by the DNA replication and damage checkpoint pathways. Proc Natl Acad Sci U S A 100:6628-33