The Use of a Drosophila Laminin A Mutant as a Model for Gestational Diabetes. Joana M. Hubickey, Lauren Perkins- Ross, Laura K. Reed. University of Alabama , Tuscaloosa , AL.

   Mutations in the Laminin A (LanA) gene show significant metabolic effects on Drosophila melanogaster adults; these include changes in TAG storage and body weight. Since these phenotypes correlate to the development of diabetes, this finding led us to our present study. We aim to model gestational diabetes in Drosophila using a previously implicated LanA mutant. In humans, gestational diabetes is characterized by high blood glucose and triglyceride levels in the mothers, as well as the mothers giving birth to larger babies. Therefore, we measured the following phenotypes in the flies; total glucose concentration, total triglyceride concentration, egg volume, and pupae weight of the Drosophila LanA mutant, 1389B, in comparison to its wildtype counterpart Canton S (CSB). The results showed that the mutant flies had significantly higher glucose concentrations, and lay larger eggs than the wildtype, which correlates to what is seen in humans. However, the mutant had significantly lower lipid concentrations, and pupae weight than the wildtype. A second aspect of the experiment was the effect of dietary perturbations on the phenotypes. The specialty diets consisted of 6 sugar, 12% sugar, and 1.5% fat. The 6% sugar and 1.5% fat diet caused the most variance in glucose concentration, lipid concentration, and pupae weight in the mutant fly from the wildtype. Moreover, all three specialty diets caused significant variation in egg volume in the mutant while the egg volume of the wildtype remained stable. Additionally, we found that age of the mother dramatically affects egg volume in the mutant. 15 day old mothers laid significantly smaller eggs than the wildtype, while 30 day old mothers laid significantly larger eggs. These findings support the continued explanation of this model for gestational diabetes.