Characterizing the impact of oocyte nutrient-sensitive genes on reproductive aging in Caenorhabditis elegans
| dc.contributor.author | Rossander, Emma | |
| dc.date.accessioned | 2026-02-23T17:15:07Z | |
| dc.date.available | 2026-02-23T17:15:07Z | |
| dc.date.issued | 2025 | |
| dc.description.abstract | Reproductive aging is the gradual decline in reproductive function over time, encompassing reductions in fertility, hormonal changes, and diminished germ cell quality. This process is highly sensitive to nutrient conditions, as sufficient energy availability is essential for maintaining reproductive function. However, nutrient surplus may accelerate aging and impair fertility. Prior studies have demonstrated that Caenorhabditis elegans (C. elegans) exposed to a high-glucose diet exhibit reduced reproductive capacity and compromised oocyte quality. Poor oocyte quality is a well-documented contributor to reproductive dysfunction in both C. elegans and humans, underscoring the importance of understanding the molecular mechanisms that influence reproductive health under obesogenic diets. Genes whose transcription is regulated in a nutrient-sensitive manner play a critical role in mediating the relationship between diet and reproductive function. This study aimed to determine the impact of two such genes, icmt-1 and psme-4, on the reproductive capacity of C. elegans by using RNAi-mediated knockdown. C. elegans were exposed to lifelong RNAi and subject to elevated glucose exposure (20 mM glucose) starting at the fourth larval stage to coincide with establishment of the reproductive system. To assess the reproductive capacity in aging worms, C. elegans were mated on day five (D5) of adulthood, and their reproductive success was evaluated based on progeny production. Additionally, D5 oocytes were imaged using DIC imaging to assess morphological changes and overall oocyte quality in response to gene knockdown and high-glucose exposure. This study found that the RNAi knockdown of icmt-1 significantly reduced reproductive success in aging C. elegans, potentially due to systemic effects rather than direct impact on oocyte quality. Since icmt-1 regulates Ras protien localization and apoptotic pathways, its knockdown may cause widespread cellular stress and metabolic disruptions that impair reproduction. Conversely, psme-4 knockdown significantly improved age-related reproductive success and oocyte quality under glucose-enriched conditions, suggesting that reducing proteasomal activity may mitigate glucose-induced reproductive decline. psme-4 knockdown did not significantly affect reproductive capacity under normal dietary conditions, indicating that its glucose-induced upregulation may play a role in the reproductive defects observed under high-glucose conditions. These findings suggest that icmt-1 and psme-4 influence reproductive responses to dietary glucose, offering insight into the genetic basis of diet-induced infertility. | |
| dc.description.reviewstatus | Unreviewed | |
| dc.description.scholarlevel | Undergraduate | |
| dc.identifier.uri | https://hdl.handle.net/1828/23342 | |
| dc.language.iso | en | |
| dc.subject.department | Department of Biology | |
| dc.title | Characterizing the impact of oocyte nutrient-sensitive genes on reproductive aging in Caenorhabditis elegans | |
| dc.type | Honours thesis |