Abstract
Ethanol tolerance, alcohol dehydrogenase (ADH; EC 1.1.1.1) activity, and tissue-specific expression were examined in species of the cardini group of Drosophila using D. melanogaster as a standard of comparison. In contrast to most fruit-breeding species, all cardini species examined, two from the cardini subgroup and five from the dunni subgroup, were ethanol sensitive (LC50 < or = 2.05%) and the mean ADH activity of males ranges from only 8 to 16% that of D. melanogaster AdhFF. Among all seven cardini species, there were small but significant differences in ethanol tolerance and ADH activity. Differences in enzyme mobility were in accordance with the proposed phylogeny for the dunni-subgroup species. ADH is expressed in the fat body and midgut. Males of D. acutilabella and of D. belladunni have significantly less ethanol tolerance and express less ADH activity than females in zymograms and histological preparations.
