DNA replication is a fundamental process that includes the accurate duplication of the genome as well as the re-establishment of chromatin modifications and epigenetic information. DNA damage interferes with replication fidelity, leading to an accumulation of mutations and chromosomal translocations, which cause genome instability. The DNA damage response (DDR) functions to resolve replication problems by recruiting repair proteins, activating checkpoints and promoting apoptosis. Cancers are characterized by genome instability and have a greater need for functional DDR pathways. This provides opportunities for therapeutic intervention, and in recent years, inhibitors have been developed targeting components of the DDR. The overall goal of this proposal is to elucidate the mechanisms of genome maintenance that operate during DNA replication. To address this broad goal, I propose three aims ? 1) To determine the mechanisms by which the single strand DNA binding protein, RPA, regulates the DDR protein, SMARCAL1 2) Discovery and functional characterization of a novel alternative single strand DNA binding protein and 3) Mechanistic understanding of how DNA repair proteins work in the context of chromatin structure.
While aims 1 and 2 will be completed by the end of my pre-doctoral studies, aim 3 represents the research direction I will adopt in my post-doctoral work. To accomplish these aims, I will utilize new methods such as single molecule, genome wide and proteomic approaches, as well as biochemical, molecular and genetic techniques. Completion of the proposed aims will yield significant insights into novel genome maintenance pathways and will further our understanding of the mechanisms underlying cancer biogenesis.

Public Health Relevance

Genomic instability is an underlying hallmark of cancers, and in recent years, therapies based on inhibiting the DNA damage response (DDR) have proven useful for targeting tumors lacking specific DDR functions. The complexity of cellular genome maintenance pathways may result in partial redundancy and contributes to drug resistance in certain genetic backgrounds. This proposal aims to provide critical insights into these pathways utilizing cellular, biochemical, proteomic and genetic approaches.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Project #
5F99CA212435-02
Application #
9354425
Study Section
Special Emphasis Panel (ZCA1)
Program Officer
Mcguirl, Michele
Project Start
2016-09-21
Project End
2018-03-31
Budget Start
2017-09-01
Budget End
2018-03-31
Support Year
2
Fiscal Year
2017
Total Cost
Indirect Cost
Name
Vanderbilt University Medical Center
Department
Biochemistry
Type
Schools of Medicine
DUNS #
965717143
City
Nashville
State
TN
Country
United States
Zip Code
37240
Bhat, Kamakoti P; Krishnamoorthy, Archana; Dungrawala, Huzefa et al. (2018) RADX Modulates RAD51 Activity to Control Replication Fork Protection. Cell Rep 24:538-545
Bhat, Kamakoti P; Cortez, David (2018) RPA and RAD51: fork reversal, fork protection, and genome stability. Nat Struct Mol Biol 25:446-453
Dungrawala, Huzefa; Bhat, Kamakoti P; Le Meur, Rémy et al. (2017) RADX Promotes Genome Stability and Modulates Chemosensitivity by Regulating RAD51 at Replication Forks. Mol Cell 67:374-386.e5