Regulation of enzyme activities in Drosophila: genetic variation affecting induction of glucose 6-phosphate and 6-phosphogluconate dehydrogenase in larvae.

The genetic basis of modulation by dietary sucrose of the enzyme activities glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD) activities in third instar larvae of Drosophila melanogaster was investigated, using isogenic lines derived from wild populations. Considerable genetically determined variation in response was detected among lines that differed only in their third chromosome constitution. Comparison of cross-reacting material between a responding and a nonresponding line showed that the G6PD activity variation is due to changes in G6PD protein level.

Autosomal factors with correlated effects on the activities of the glucose 6-phosphate and 6-phosphogluconate dehydrogenases in Drosophila melanogaster.

Isogenic lines, in which chromosomes sampled from natural populations of C. melanogaster are substituted into a common genetic background, were used to detect and partially characterize autosomal factors that affect the activities of the two pentose phosphate pathway enzymes, glucose 6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD). The chromosome 3 effects on G6PD and 6PGD are clearly correlated; the chromosome 2 effects, which are not so great, also appear to be correlated, but the evidence in this case is not so strong.

The effects of lethal selection on the EST-6 to PGM region of chromosome 3 in Drosophila melanogaster.

A powerful means of studying the effects of selection on chromosome segments in Drosophila melanogaster has been described by Clegg et. al. (1976, 1978).

Studies of esterase-6 in Drosophila melanogaster. II. The genetics and frequency distributions of naturally occurring variants studied by electrophoretic and heat stability criteria.

Measurements of the electrophoretic mobility and thermostability of esterase-6 allozymes have been used to determine the amount of allelic variation at the esterase-6 locus in Drosophila melanogaster. We studied 398 homozygous lines obtained from four natural populations. Use of a spectrophotometric assay for esterase-6 activity has allowed precise quantitation of heat-stability variants.

Studies of esterase 6 in Drosophila melanogaster. I. The genetics of a posttranslational modification.

A locus has been found, an allele of which causes a modification of some allozymes of the enzyme esterase 6 in Drosophila melanogaster. There are two alleles of this locus, one of which is dominant to the other and results in increased electrophoretic mobility of affected allozymes. The locus responsible has been mapped to 3-56.