Natural and synthetic alleles provide complementary insights into the nature of selection acting on the Men polymorphism of Drosophila melanogaster.

ABSTRACT: Two malic enzyme alleles, Men(113A) and Men(113G), occur at approximately equal frequency in North American populations of Drosophila melanogaster, while only Men(113A) occurs in African populations. We investigated the population genetics, biochemical characteristics, and selective potential of these alleles. Comparable levels of nucleotide polymorphism in both alleles suggest that the Men(113G) allele is not recently derived, but we find no evidence in the DNA sequence data for selection maintaining the polymorphism. Interestingly, the alleles differ in both V(max) and K(m) for the substrate malate. Triglyceride concentration and isocitrate dehydrogenase (IDH) and glucose-6-phosphate dehydrogenase (G6PD) activities are negatively correlated with the in vivo activities of the Men alleles.

SUBMITTER: Merritt TJ 

PROVIDER: S-EPMC1456097 | biostudies-literature | 2005 Dec

REPOSITORIES: biostudies-literature