Project description:Differences in the selective pressures experienced by males and females are believed to be ubiquitous in dioecious organisms and are expected to result in the evolution of sexually antagonistic alleles, thereby driving the evolution of sexual dimorphism. Negative genetic correlation for fitness between the sexes has been documented, however, the identity, number and location of loci causing this relationship are unknown. Here we show that a large proportion of Drosophila melanogaster transcripts are associated with the interaction between genomic haplotype and gender and that at least 8% of loci in the fly genome are currently evolving under sexually antagonistic selection.
Project description:Differences in the selective pressures experienced by males and females are believed to be ubiquitous in dioecious organisms and are expected to result in the evolution of sexually antagonistic alleles, thereby driving the evolution of sexual dimorphism. Negative genetic correlation for fitness between the sexes has been documented, however, the identity, number and location of loci causing this relationship are unknown. Here we show that a large proportion of Drosophila melanogaster transcripts are associated with the interaction between genomic haplotype and gender and that at least 8% of loci in the fly genome are currently evolving under sexually antagonistic selection. We measured gene expression of adult males and females of Drosophila melanogaster from 15 hemiclone lines, showing either high-male/low-female fitness, high-female/lowmale fitness or average fitness in both sexes. Data from four replicates for each sex/line are presented, giving a total of 120 arrays.
Project description:In Drosophila melanogaster, mating radically transforms female physiology and behavior. Post-mating responses include an increase in the oviposition rate, a reduction in female receptivity, and an activation of the immune system . The fitness consequences of mating are similarly dramatic – females must mate once in order to produce fertile eggs, but additional matings have a clear negative effect. Previously, microarrays have been used to examine gene expression of females differing in their reproductive status with the aim of identifying genes influenced by mating. However, since only virgin and single mated females were compared, transcriptional changes associated with reproduction (under natural selection) and the effects of male-induced harm (under sexually antagonistic selection) cannot be disentangled. We partitioned these fundamentally different effects by instead examining the expression profiles of virgin, single mated and double mated females. We found substantial effects relating to reproduction and further effects that are only attributable to a second mating. Immune response genes dominate this male-induced harm effect indicating that the cost of mating may be due partly to this system's activation. We propose that both sexually antagonistic and natural selection have been important in the evolution of the innate immunity genes, thereby contributing to the sexual dimorphismand rapid evolution at these loci. Keywords: Female response to mating
Project description:Thermal acclimation study on Drosophila melanogaster reared at 3 different temperatures (12, 25, and 31oC). The proteomic profiles of D. melanogaster under these different temperatures were analyzed and compared using label-free tandem mass spectrometry.