Evolutionary conservation of the chromosomal configuration and regulation of amylase genes among eight species of the Drosophila melanogaster species subgroup

Nuclear DNA was extracted from each of the eight species comprising theDrosophila melanogaster species subgroup. Southern hybridization of thisDNA by using a molecular probe specific for the alpha-amylase coding regionshowed that the duplicated structure of the amylase locus, first found inD. melanogaster, is conserved among all species of the melanogastersubgroup. Evidence is also presented for the concerted evolution of theduplicated genes within each species. In addition, it is shown that theglucose repression of amylase gene expression, which has been extensivelystudied in D. melanogaster, is not confined to this species but occurs inall eight members of the species subgroup. Thus, both the duplicated genestructure and the glucose repression of Drosophila amylase gene activityare stable over extended periods of evolutionary time.