Dictyostelium Discoideum Case Study

The development of Dictyostelium discoideum was compared in two varying temperatures after 30 hrs of development. The D. discoideum cultures were observed for developmental differences in multicellular aggregate forms of slugs and fruiting bodies in 10°C and 22°C. The mean percent of organisms was higher in less developed stages for both temperatures. The average percent of aggregates were higher at 41.625% for the D. discoideum cultures that developed at 22°C. The average precent of fingers were higher at 41.41% for the D. discoideum cultures that developed at 10°C. The results from this study suggest that D. discoideum development is not affected by change in temperature. The species used for this study is the Amoebozoan, Dictyostelium
disciodeum. In a study conducted by Bonner and Lamont, the morphology and behaviors of different cellular slime molds were analyzed under different conditions. They found that in D. disciodeum thrived equally on nutrient soil and a non-nutrient agar dishes (Bonner & Lamont, 2005). Similarly to the experiment preformed by Bonner and Lamont, we evaluated growth patterns of D. disciodeum on non-nutrient agar dishes. Another study conducted by Fisher, found that certain genetic factors increase the movement and development of D. disciodeum amoebae within a temperature gradient (Fisher,1997). Within this study, we examined the effect of differing temperature on slug and sporangia development in D. disciodeum. Our hypothesis was slug and sporangia development would increase in the slime molds growing in warmer temperatures. Using the methods described below, we examined and analyzed our hypothesis. The Dictyostelium discoiodeum amoebae culture was prepared for this experiment. A culture of D. discoideum amoebae and E. coli were added to an agar dish and allowed 29 hours of development at room temperature. They cultures were refrigerated and continued to slowly develop for several days. Before being used for this experiment, the D. discoideum amoebae were rinsed with cold BSS and centrifuged to separate and harvest the aggregation-competent
We recorded the number of cells in each stage of development from least developed to more developed, which included aggregate/hats, fingers, slugs, culminating forms, and sporangia (fruiting bodies). Using the data pool that was collected, we calculated the totals and percent of organisms in each stage of development and compared the effects of temperature on the development of Dictyostelium discoideum. Using the percent of organisms at each stage, we statistically analyzed the D. discoideum cultures by calculating the mean and stand deviation. After calculating the total number of organisms at each experimental group, we determined the percentage of organism in the five developmental stages for each group. Using these parentages, we further calculated the average percent of organisms overall within each developmental stage. These results are shown above in figure 1, the blue bars represent the average percent of organisms for each stage that developed at 10 °C and the orange bars represent the organisms which developed at 22 °C. The average percent of organisms for both temperature was higher in the less developed forms. There was more development of culminating forms and sporangia in the D. discoideum that matured at