Adaptation to a Starch Environment and Regulation of alpha-Amylase in Drosophila

The adaptation to glucose and starch foods insix species, D. melanogaster, D.virilis, D. saltans, D. funebris,D. levanonensis and D. americana, wasstudied by measuring productivity. D.melanogaster and D. virilis adapted more to thestarch environment than to the glucose environment,while D. saltans adapted more to the glucoseenvironment than to the starch environment. D.funebris, D. levanonensis, and D. americana did not distinctlyadapt to either environment. In addition, the regulationof amylase in the six species was investigated bymeasuring the levels of amylase activity with glucoseand starch food environments. The levels of amylaseactivity in D. levanonensis and D.saltans were substantially low, indicating thatthese species cannot utilize starch as a carbon source.The starch-adapted species, D. melanogaster and D.virilis, showed higher levels of amylase activitywith the starch environment and higher inducibility.These results suggest that changing the regulation ofamylase is important for the adaptation to a starch environment inDrosophila.