In the Haase lab most of the researchers study the cell cycle of the budding yeast Saccharomyces cerevisiae, an important model eukaryote. Much of the Haase lab’s efforts center on piecing together a complicated network of cyclically transcribed transcription factors. This transcription factor network plays an important role along with cyclins and CDKs in driving the different stages of the cell cycle in eukaryotes. Several researchers in the Haase lab also study the yeast metabolic cycle and other biological oscillators in other microorganisms.
In the Haase lab I am working with graduate student Chun-Yi Cho who has been studying the coupling of the cyclin/CDKs and the transcription factor network. He is interested in how specifically the cyclin/CDKs increase the robustness of the transcription factor oscillations.
For my project, I am studying the phenotype of one specific transcription factor of interest, Sfg1. Our first hypothesis was that this gene might play a role in the yeast cells determining nutrient levels in their environment and then altering their budding rate accordingly. However, it seems that Sfg1’s role and methods in S.cerevisiae may be more complicated than I initially thought and we are conducting more experiments to better understand this transcription factor. For this project, I carry out many synchronized time courses in different medias with both a wild type yeast and the Δsfg1 mutant, which lacks the Sfg1 gene. I then find the ratio of budded cells throughout the time course and plot this data to get a budding curve, which shows the rate at which the synchronized cells are budding. By comparing the budding curves of the two strains, Chun-Yi and I have seen some interesting ways in which Δsfg1 affects budding yeast in different medias. In the next week or two we plan to use yeasts with a different knocked out gene, as well as a different method of synchronization to better understand Sfg1’s specific place in the transcription factor network. We also hope to understand possible confounding factors in the experiments.
So far I feel like I am learning a lot about the transcription factor network and collecting data. Chun-Yi has been helpful in teaching me how to conduct different experiments and in pointing me towards many relevant research papers. Hopefully with more experiments we will learn more about the workings of the Sfg1 transcription factor.
