Artemis has been shown recently to be involved in a human severe combined immunodeficiency syndrome (SCID) in which an absence of development of T and B cells is observed. This defect is due to a requirement for Artemis in the coding joint formation step of V(D)J recombination. In addition, patient cell lines were shown to be hypersensitive to ionizing radiation suggesting that Artemis is also involved in cellular responses to DNA damage. The goals of this application are to characterize the function of Artemis in regard to its role in mediating the cellular response to DNA damage. Specifically, we will determine the nature of proteins that Artemis interacts with, and examine its cellular localization before and exposure to genotoxic agents. Our findings show that Artemis is rapidly phosphorylated upon exposure of cells to DNA damage including that induced by both IR and UV. We have also shown that this phosphorylation is mediated by the PI3 kinases DNA-PK, ATM, and ATR. We will characterize this phosphorylation of Artemis and prepare phosphospecific antibodies that will be utilized for functional studies of Artemis. These functional studies will be conducted on cells defective in Artemis to determine its role in either DNA repair and/or cell cycle checkpoint pathways. It is expected that these studies will elucidate the function of Artemis in DNA damage response pathways, and thus provide an explanation for the radiosensitivity of the RS-SCID syndrome. Finally, we will prepare a knock-in mutant of Artemis in the mouse that is mutated at sites of phosphorylation mediated by ATM. This experiment is designed to determine if the modification of Artemis by ATM is involved in the immunodeficiency observed in AT patients.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA096574-05
Application #
7394440
Study Section
Chemical Pathology Study Section (CPA)
Program Officer
Pelroy, Richard
Project Start
2004-03-01
Project End
2010-02-28
Budget Start
2008-03-01
Budget End
2010-02-28
Support Year
5
Fiscal Year
2008
Total Cost
$293,511
Indirect Cost
Name
University of Texas MD Anderson Cancer Center
Department
Genetics
Type
Other Domestic Higher Education
DUNS #
800772139
City
Houston
State
TX
Country
United States
Zip Code
77030
Yan, Yiyi; Zhang, Xiaoshan; Legerski, Randy J (2011) Artemis interacts with the Cul4A-DDB1DDB2 ubiquitin E3 ligase and regulates degradation of the CDK inhibitor p27. Cell Cycle 10:4098-109
Yan, Yiyi; Akhter, Shamima; Zhang, Xiaoshan et al. (2010) The multifunctional SNM1 gene family: not just nucleases. Future Oncol 6:1015-29
Wang, Haiyong; Zhang, Xiaoshan; Geng, Liyi et al. (2009) Artemis regulates cell cycle recovery from the S phase checkpoint by promoting degradation of cyclin E. J Biol Chem 284:18236-43
Zhang, X; Zhu, Y; Geng, L et al. (2009) Artemis is a negative regulator of p53 in response to oxidative stress. Oncogene 28:2196-204
Geng, Liyi; Zhang, Xiaoshan; Zheng, Shu et al. (2007) Artemis links ATM to G2/M checkpoint recovery via regulation of Cdk1-cyclin B. Mol Cell Biol 27:2625-35
Ahkter, Shamima; Richie, Christopher T; Zhang, Nianxiang et al. (2005) Snm1-deficient mice exhibit accelerated tumorigenesis and susceptibility to infection. Mol Cell Biol 25:10071-8
Zhang, Xiaoshan; Succi, Janice; Feng, Zhaohui et al. (2004) Artemis is a phosphorylation target of ATM and ATR and is involved in the G2/M DNA damage checkpoint response. Mol Cell Biol 24:9207-20
Akhter, Shamima; Richie, Christopher T; Deng, Jian Min et al. (2004) Deficiency in SNM1 abolishes an early mitotic checkpoint induced by spindle stress. Mol Cell Biol 24:10448-55