Mitochondrial ARtificial Targeting (or MART) to Augment mtDNA Repair

Mitochondria, often referred to as the powerhouses of cells, are essential for producing the energy required to sustain life. However, they are also a significant source of harmful molecules called reactive oxygen species, which can damage mitochondrial DNA and impair cellular function. This damage is further exacerbated by external factors like pollution, potentially leading to a myriad of maladies.

This project aims to enhance the natural repair mechanisms of mitochondrial DNA by improving the targeting of key repair enzymes to mitochondria without disrupting their other cellular roles. In addition to advancing fundamental knowledge, this research fosters interdisciplinary collaboration, engages students and researchers at all levels, and promotes outreach efforts to inspire the next generation of scientists.

The dovetailing of cutting-edge computational modeling and experimental methods will allow exploration of innovative ways to protect mitochondrial health while contributing to future strategies to mitigate mitochondrial dysfunction.

This project addresses a critical gap in the understanding of mitochondrial base excision repair (mtBER), a pathway essential for maintaining mitochondrial DNA (mtDNA) integrity in the face of oxidative damage. The project will focus on re-engineering the mitochondrial localization signals of five DNA glycosylases that specifically excise oxidized DNA damage, namely OGG1, NTHL1, NEIL1, NEIL2, and NEIL3 to improve their targeting to mitochondria while preserving their nuclear localization.

A novel computational framework will be used to optimize mitochondrial targeting signals through sequence modifications that enhance mitochondrial import efficiency. The re-engineered glycosylases will be validated experimentally for localization and their enzymatic activity assessed through biochemical assays. The functional impact of enhanced mitochondrial localization will be evaluated by examining oxidative damage repair capacity, mtDNA stability, and mitochondrial function.

Overall, this research will address the extent to which glycosylase trafficking to the mitochondria could serve a protective role against oxidized DNA damage and improve repair, offering critical insights into the mechanisms safeguarding mitochondrial integrity. This project is jointly funded by the Genetic Mechanisms program in the Division of Molecular and Cellular Biosciences and the Established Program to Stimulate Competitive Research (EPSCoR).

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.