Graduation Year
2020
Document Type
Master's Thesis
Degree
Master of Science
Program
Biological Science
Program Director
Meredith Protas, PhD
First Reader
Chuankai Zhou, PhD
Second Reader
Tyler Johnson, PhD
Abstract
Mitochondrial dysfunction is a hallmark of aging and has been closely tied to age-related pathologies, such as cancer, cardiovascular diseases, neurodegenerative disorders, and metabolic syndromes. Though the consequences of mitochondrial defects are well documented, little is known about the molecular events that occur with age that transform healthy mitochondria into dysfunctional ones. Past studies have attempted to uncover the underlying proteomic changes in age, however, most of these results do not take into account population heterogeneity often associated with aging, thus highlighting the need for single-cell analysis. Technological barriers have impeded in-depth proteomic studies of aging mitochondria on a single cell level. We have created a new apparatus and method, collectively known as the High-Throughput Aging System (HTAS), which is optimized for the purification of aged Saccharomyces cerevisiae cells.
Utilizing HTAS, we performed a microscopy-based screen to quantify and track the localization of mitochondrial proteins during aging through the use of GFP fusion proteins. Our screen has revealed several age-related phenotypes such as mislocalization and depletion of specific mitochondrial proteins, including some of which are essential for cell viability. By highlighting proteins that undergo the most change in age, our results provide the first steps in identifying key pathways that may become compromised during the aging process. Thus, the proteins highlighted in our screen may further act as markers of mitochondrial dysfunction that can be targeted for repair in age and age-related diseases.