Understanding Vacuole Related Mechanisms Under Toxic Metal Stress
By: Ramon Rodriguez
Department: Cellular & Molecular Biology
Faculty Advisor: Dr. Mark Chan
The vacuole in Saccharomyces cerevisiae is responsible for aiding in protein degradation and serves as a storage unit for the cell. In addition, the vacuole is also responsible for storing harmful or toxic metals which in large amounts have been known to cause cellular toxicity. Understanding vacuole related molecular mechanisms within toxic heavy metal environments could further our insight into how the structure of an organelle may affect the functionality of the overall cell. This study focuses on different concentrations of copper chloride, lithium chloride, iron 2 chloride, iron 3 chloride, and sodium chloride and its effects on the vacuole measured in volume. To quantify these results, we studied BY4741 cell strains tagged with a green fluorescent protein on the vacuole membrane. This fluorescent protein will allow us to create a 3D model of the vacuoles to obtain its volume.
Confocal microscopy was used to gather images of the vacuoles that had been exposed to various concentrations of copper chloride and lithium chloride. These images were then analyzed using image J, an analytical imaging software program. Vacuoles exposed to higher concentrations of copper chloride demonstrated a significant increase in both size and volume, whereas vacuoles exposed to lower concentrations displayed a smaller size and volume relative to the size of the cell. Moreover, the vacuoles exposed to lithium chloride concentrations have shown signs of affecting vacuole inheritance. Future experiments with vacuole related mutant strains grown on toxic metal agar plates will further our insight into understanding cell growth with altered vacuole related molecular mechanisms.