PROJECT SUMMARY
Arsenic is a widespread toxin in drinking water that affects millions of people, increasing the risks of
neurodegenerative and cardiovascular diseases and cancers. High doses of arsenic cause DNA damage and
genome instability. However, the health effects associated with low-dose arsenic are controversial. Recently,
we discovered that large networks of DNA damageome proteins (DDPs) promote DNA damage and genome
instability (Xia et al. Cell 2019). We also found that Aquaporin 3 (AQP3) is a new lung cancer-associated DDP.
This application describes the mechanism by which AQP3 interacts with low-dose arsenic to promote DNA
damage, an approach to map AQP3, arsenic-induced double-strand break (DSB) hotspots, and associated
mutation signatures in human cells and populations. Specifically, it will (1) provide mechanistic insights into
how AQP3 potentiates arsenic-induced DNA Damage, (2) map DSBs caused by AQP3 and low-dose arsenic
interactions, and (3) identify AQP3 and arsenic-induced genome instability and mutational signatures. The
proposed studies will bring function to endogenous DNA damage and the DNA damageome proteins when
interacting with environmental toxicants. Mechanistic insights into how low-dose arsenic interacts with risk
genes are critical knowledge for the prevention, diagnosis, and treatment of arsenic-associated diseases. This
project will identify early biomarkers to predict the long-term health impacts of arsenic, and uncover mutational
signatures to infer cancer etiology and reveal past arsenic exposure. Lastly, the platform developed in this
proposal will be useful for uncovering the effects of environmental toxicants and/or carcinogens with host
genes. In addition to its scientific proposal, this application also lays out a comprehensive training plan that will
help the candidate achieve his career goal of becoming an independent investigator who will apply his unique
background in endogenous DNA damage to better understand genes-exogenous environmental agents (e.g.
arsenic) interactions. Further interdisciplinary knowledge in environmental health, formal bioinformatics, and
quantitative genomics training, as well as CRISPR and organoid training will put him in a unique position to
tackle challenging environmental health research problems. Dr. Chris Amos, Director of the Institute for Clinical
and Translational Research at the Baylor College of Medicine will lead a group of co-mentors and advisory
committee members to provide advice on research and career development with advancement to a tenure
track position.