Extended vs. Condensed: Determination of Mitochondrial Compartment Structure in Saccharomyces cerevisiae

Mitochondria are organelles that produce ATP, and are also responsible for signaling and cell death. Wild-type yeast mitochondria exhibit extended mitochondrial structure, described as long and tubular networks. Induction of mutations into these cells causes a percentage to exhibit condensed mitochondrial compartments that can be described as "blobby" under a microscope. The purpose of this experiment is to decide whether or not mitochondrial structure of a given daughter cell is dependent on structure of the mother cell. Two strains of yeast were studied, one with an mdm33Δ, and the other strain with a gem1Δ. To test the hypothesis, we used the idea that an isolated colony has arisen from one single cell, the "mother cell," and therefore the percentage of extended vs. condensed mitochondrial structure was counted from a heavy smear (representing the mother cell) and in 10 colonies isolated from this smear. These distributions were examined using mitochondrial targeted GFP. Upon counting the structures of the "mother cells", and 10 colonies arisen from this cell, it was determined that the distribution of morphology is quite variable, with 40-66% extended, and 34-57% condensed. Because the distribution is so variable, we need to further focus on the issues associated with the assay, such as the brightness of the GFP, and perhaps continue with more counts in order to obtain a more balanced distribution.