Graduation Year
2024
Document Type
Master's Thesis
Degree
Master of Science
Program
Biological Science
Program Director
Meredith Protas, PhD
First Reader
Chuankai Zhou, PhD
Second Reader
Fan Zheng, PhD
Abstract
In eukaryotes, mitochondria have their own ribosomes called mitoribosomes (MRC), that synthesize proteins essential for oxidative phosphorylation (OXPHOS). Mutations to mitochondrial ribosomal proteins (MRP) or assembly factors can lead to various pathologies including cardiomyopathies, hearing loss, and cancer. However, the process by which the mitochondrial ribosome is assembled remains largely unknown. So far there are only ~20 MRC assembly factors being identified. In contrast, its counterpart in cytosol, the cytosolic ribosomal assembly requires over 200 assembly factors, implying that more assembly factors for the mitochondrial ribosomes await to be identified. This study focuses on exploring the protein components involved in MRC assembly and nucleoid dynamics in Saccharomyces cerevisiae (S. cerevisiae). To facilitate the studying of MRC, we took advantage of a yeast knockdown strain to alter mitochondrial structure to discern the compartments of the mitochondria. Ribosomes are assembled in the nucleolus of the nucleus, and we hypothesize a similar MRC assembly condensate is present in the mitochondria near nucleoids. To observe the dynamics of nucleoids in S. cerevisiae, we took advantage of the fluorescence recovery after photobleaching (FRAP) of fluorescently tagged mitochondrial DNA (mtDNA) associated protein, Abf2. Overall, this study expands the knowledge base of MRCs by finding assembly factor localization and determining the dynamics of nucleoids.