DNA interstrand crosslinking agents are highly deleterious lesions and potent mutagens to which humans are exposed from both exogenous and endogenous sources. In addition, this class of drugs, which include cyclophosamide, cis-platin, busulfan, and mitomycin C, are widely used as anti-cancer chemotherapeutics. Nevertheless, the cellular responses to these drugs in terms of both the cell cycle and DNA repair remain poorly understood. During the last grant cycle we were able to identify a number of novel proteins involved in the cellular ICL response. In addition, we have developed a number of new assays that have increased our ability to probe the mechanisms of ICL repair. There appears to be at least two distinguishable pathways of ICL repair in mammalian cells one of which occurs in G1/G0, and a second that is induced by stalled replication forks during S phase. The focus of this project will be on increasing our understanding of the various aspects of the S phase pathway of ICL repair. Specifically, we examine recruitment of repair and checkpoint proteins to ICLs using a novel laser microirradiation approach which can be used to crosslink psoralen to a defined subregion of the mammalian nucleus. Secondly, we will examine the mechanisms of fork collapse, and define proteins that are directly involved in ICL removal. Thirdly, we will investigate the role of candidate proteins in various stages of ICL repair processing. Fourthly, we will isolate stalled replication forks and using mass spectrometry we will identify proteins involved in repair and checkpoint functions that are recruited to these structures. Together the successful completion of these aims should greatly increase our understanding of the mechanisms by which ICLs are processed in mammalian cells, and thereby lead to potential new or enhanced chemotherapies for cancer.
This Project is part of a multicomponent Program Project with the theme of understanding the processing of complex DNA damage by mammalian cells. The significance to human health is to generate new knowledge and paradigms for modeling DNA repair of DNA interstrand crosslinks (ICLs), to improve therapy using ICL-inducing compounds, and to identify new therapeutic targets for cancer treatment.
|Tomida, Junya; Takata, Kei-Ichi; Bhetawal, Sarita et al. (2018) FAM35A associates with REV7 and modulates DNA damage responses of normal and BRCA1-defective cells. EMBO J 37:|
|Klages-Mundt, Naeh L; Li, Lei (2017) Formation and repair of DNA-protein crosslink damage. Sci China Life Sci 60:1065-1076|
|Malaby, Andrew W; Martin, Sara K; Wood, Richard D et al. (2017) Expression and Structural Analyses of Human DNA Polymerase ? (POLQ). Methods Enzymol 592:103-121|
|Manandhar, Mandira; Lowery, Megan G; Boulware, Karen S et al. (2017) Transcriptional consequences of XPA disruption in human cell lines. DNA Repair (Amst) 57:76-90|
|Mukherjee, Anirban; Vasquez, Karen M (2016) Tools to Study the Role of Architectural Protein HMGB1 in the Processing of Helix Distorting, Site-specific DNA Interstrand Crosslinks. J Vis Exp :|
|Zhang, Xiaoshan; Lu, Xiaoyan; Akhter, Shamima et al. (2016) FANCI is a negative regulator of Akt activation. Cell Cycle 15:1134-43|
|Mukherjee, Anirban; Vasquez, Karen M (2016) HMGB1 interacts with XPA to facilitate the processing of DNA interstrand crosslinks in human cells. Nucleic Acids Res 44:1151-60|
|Lange, Sabine S; Tomida, Junya; Boulware, Karen S et al. (2016) The Polymerase Activity of Mammalian DNA Pol ? Is Specifically Required for Cell and Embryonic Viability. PLoS Genet 12:e1005759|
|Wood, Richard D; Doublié, Sylvie (2016) DNA polymerase ? (POLQ), double-strand break repair, and cancer. DNA Repair (Amst) 44:22-32|
|Tian, Yanyan; Paramasivam, Manikandan; Ghosal, Gargi et al. (2015) UHRF1 contributes to DNA damage repair as a lesion recognition factor and nuclease scaffold. Cell Rep 10:1957-66|
Showing the most recent 10 out of 83 publications