Organelle Size Scaling Regulation in Saccharomyces cerevisiae Optogenetically Grown to Immense Cell Size
By: Brenda Sofia Garibay
Department: Cellular & Molecular Biology
Faculty Advisor: Dr. Mark Chan
The yeast Saccharomyces cerevisiae has organelles that serve as biochemical reactors in the cell; specifically, the vacuole maintains pH, ion homeostasis, and degrades proteins. Previous studies found that the vacuole organelle in S. cerevisiae shows a scaling trend with cell size, suggesting a size-coordination regulating mechanism. Inheritance plays a significant role in organizing vacuole size. Yeast strains defective in vacuole inheritance, vac8Δ and vac17Δ, result in a loss of vacuole to cell size scaling compared to wildtype. In this study, we work to uncover how vacuole inheritance perturbation causes a change in size-scaling through optogenetics. I expect to generate enlarged cells with enlarged vacuoles by optogenetically blocking Bem1, and that vacuole size will continue to accumulate due to the loss of inheritance. Furthermore, I will measure the effects of genetically inhibiting vacuole inheritance in these optogenetically enlarged cells using the vac8Δ and vac17Δ. I have engineered a cell line that utilizes an optogenetics system to temporally inhibit cell budding, which leads to a significant increase in cell size. Understanding the cellular mechanisms present during a cell’s response to excess vacuole and size contributes to advancing the knowledge of biological systems and translating new therapeutic approaches to clinical practice.