Alcohol dehydrogenase polymorphism in populations of Drosophila melanogaster. II. Relation between ADH activity and adult mortality

Strains of Drosophila melanogaster homozygous either for the AdhF or the Adhs allele, were kept on food supplemented with ethanol. After 90 generations these strains (FFE and SSE) were tested for tolerance to ethanol and compared with control strains (FFN and SSN) from regular food. The E strains showed increased tolerance to ethanol, both in the adult and in the juvenile life stages. In the adults the increase in tolerance was not accompanied by an increase in ADH activity. In the juvenile life stages there were significant differences in ADH activity between the E and N strains, both on regular food and on food containing ethanol. However, ADH activity was not the only factor involved in the increased tolerance to ethanol.The Adh genotype of the mother was of paramount importance to egg-to-adult survival because of a maternal effect on ethanol tolerance in the eggs and first instar larvae. Furthermore developmental times of the E strains were longer than those of the corresponding N strains. It is concluded that the adaptation to ethanol-containing food was not realised in the same way in the FFE and SSE strains.

Section: Ethanol Concentrat!on(% V/v)supporting

confidence: 85%

Section: Introductionmentioning

confidence: 99%

Development of tolerance to ethanol in relation to the alcohol dehydrogenase locus in Drosophila melanogaster 1. Adult and egg-to-adult survival in relation to ADH activity

Kerver

Delden

1985

“…These results confirm earlier conclusions that ADH takes a paramount position in the detoxification of alcohols and that genotypes who lack or have reduced ADH activity (as in the case of heterozygotes for Adh°a nd Adh positive alleles) possess increased mortalities even at low ethanol concentrations (David et al, 1976;Kamping and Van Delden, 1978;Kerver and Rotman, 1987). When using the combined viability estimates for the construction of a curve of Adh° frequency decline on ethanol food a perfect fit with the observed curve in the F/ 0 populations is obtained.…”

Section: Discussionsupporting

confidence: 88%

Selection against Adh null alleles in Drosophila melanogaster

Delden

Kamping

1988

Populations of Drosophila melanogaster polymorphic for an Adh null and an Adh positive allele (either Adhs or AdhF), were founded on regular food, on food supplemented with ethanol and on food suplemented with methanol. On ethanol-supplemented food Adh null was rapidly eliminated, but on regular food and on food supplemented with methanol a consistent decline in the frequency of the Adh null allele was also observed. Estimates of fitness, based on the rate of elimination of Adh nulls in the polymorphic populations were compared with estimates derived from egg-to-adult survival of F2's from crosses between homozygotes for Adh null alleles and homozygotes for Adh positive alleles. On 1-pentene-3-ol a rise in Adh null frequency was observed. Even in the absence of alcohol stress the Adh null genotypes are at a selective disadvantage which is relevant to the metabolic role of ADH and the Adh polymorphism in natural populations.

“…Ethanol tolerance is positively correlated with the enzymatic activity found in the fly (Oakeshott, 1976;Kamping and Van Delden, 1978). Analysis of the Colmar selected strain revealed an increase in its ADH activity (McDonald et al, 1977).…”

Section: Resultsmentioning

confidence: 99%

Alcohol tolerance and alcohol utilisation in Drosophila: Partial independence of two adaptive traits

Herrewege

David

1980

SUMMARYThree natural populations of D. melanogaster with different ethanol tolerance, and a population of D. simulans were successfully selected for an increased capacity to withstand alcohol. Alcohol utilisation, measured by the increase of life duration in the presence of low concentrations of alcohol, was clearly improved only in two cases. Alcohol tolerance and utilisation, two physiological traits that both depend on the presence of an active ADH, are thus controlled, at least partly, by different genetic mechanisms. In Drosophila species breeding on fermenting fruits or in wine cellars, both traits may be under the control of natural selection.