Freriksen Astrid, de Ruiter Barbara L A, Groenenberg Hendrik-Jan, Scharloo Willem, Heinstra Pieter W H
Department of Plant Ecology and Evolutionary Biology, Section of Evolutionary Genetics, University of Utrecht, Padualaan 8, 3584 CH Utrecht, The Netherlands, 3584 CH, Utrecht, The Netherlands.
Evolution. 1994 Jun;48(3):781-790. doi: 10.1111/j.1558-5646.1994.tb01361.x.
Prior studies showed that differences in alcohol dehydrogenase (ADH) activity across genotypes of Drosophila are decisive for the outcome of selection by ethanol. In the present paper, the effect on ADH activity and egg-to-adult survival of combinations of ethanol, propan-2-ol, and acetone in naturally occurring concentrations is examined. Propan-2-ol is converted into acetone by ADH in vitro. Acetone is considered a competitive inhibitor of ethanol for the ADH enzymes. The melanogaster-ADH-S allozyme is two times more sensitive towards inhibition by acetone than either simulans-ADH or melanogaster-ADH-F. The physiological implications of these in vitro differences for larvae were studied in short-term in vivo and long-term exposure experiments. No major differences in acetone accumulation or fitness parameters were found between the strains in response to ecologically relevant concentrations of acetone or propan-2-ol. Ethanol, however, strongly decreased egg-to-pupal survival in both Drosophila simulans strains and increased developmental time in four out of the five strains tested. Therefore, under physiological conditions only ethanol was shown to act as a selective agent on the ADH polymorphism during egg-to-pupa development in Drosophila.
先前的研究表明，果蝇不同基因型的乙醇脱氢酶（ADH）活性差异对于乙醇选择的结果具有决定性作用。在本文中，研究了自然存在浓度下乙醇、异丙醇和丙酮组合对ADH活性以及卵到成虫存活率的影响。异丙醇在体外被ADH转化为丙酮。丙酮被认为是乙醇对ADH酶的竞争性抑制剂。黑腹果蝇-ADH-S同工酶对丙酮抑制的敏感性是拟果蝇-ADH或黑腹果蝇-ADH-F的两倍。通过短期体内和长期暴露实验研究了这些体外差异对幼虫的生理影响。在响应生态相关浓度的丙酮或异丙醇时，各品系之间在丙酮积累或适合度参数方面未发现重大差异。然而，乙醇显著降低了两个拟果蝇品系中卵到蛹的存活率，并增加了所测试的五个品系中四个品系的发育时间。因此，在生理条件下，仅乙醇被证明在果蝇卵到蛹发育过程中对ADH多态性起选择作用。
