Project description:RNA was extracted from adult male and adult female Drosophila melanogaster with reversed sex-chromosome parent-of-origin (e.g. maternal-X/paternal-Y vs. paternal-X/maternal-Y)
Project description:RNA was extracted from adult male and adult female Drosophila melanogaster with reversed sex-chromosome parent-of-origin (e.g. maternal-X/paternal-Y vs. paternal-X/maternal-Y) Parent-of-origin effects were assayed in X/Y males, XY/Y males, and XY/X females. Direct comparisons were made between individuals with the same karyotype (e.g. X/Y males or XY/Y males) incorporating dye-swaps.
Project description:Intralocus sexual conflict, where males and females have different fitness optima for the same trait, has been suggested to potentially be resolved by genomic imprinting, whereby expression in offspring is altered according to parent-of-origin. However, this idea has not yet been empirically tested. Here, we designed an experimental evolution protocol in Drosophila melanogaster which enabled us to look for imprinting effects on the X-chromosome. We enforced father-to-son transmission of the X-chromosome for many generations, and compared fitness and gene expression levels between control males, males with a control X-chromosome that had undergone one generation of father-son transmission (CDX), and males with an X-chromosome that had undergone many generations of father-son transmission (MLX). Although fitness differences were consistent with lowered fitness of males with a paternally inherited X-chromosome, expression differences suggested that this was due to deleterious maternal effects rather than imprinting. We conclude that imprinting is unlikely to resolve intralocus sexual conflict in Drosophila melanogaster.
Project description:We generate 36 otherwise isogenic Drosophila melanogaster strains differing only in the geographical origin of their mitochondrial genome and Y chromosome to experimentally examine the effects of the uniparentaly inherited parts of the genome, as well as their interaction, in males. We assay gene expression through RNA-sequencing and detect an important role for both mitochondrial and Y-linked genes, as well as extensive mitochondrial-Y chromosome epistasis.
Project description:Intralocus sexual conflict, where males and females have different fitness optima for the same trait, has been suggested to potentially be resolved by genomic imprinting, whereby expression in offspring is altered according to parent-of-origin. However, this idea has not yet been empirically tested. Here, we designed an experimental evolution protocol in Drosophila melanogaster which enabled us to look for imprinting effects on the X-chromosome. We enforced father-to-son transmission of the X-chromosome for many generations, and compared fitness and gene expression levels between control males, males with a control X-chromosome that had undergone one generation of father-son transmission (CDX), and males with an X-chromosome that had undergone many generations of father-son transmission (MLX). Although fitness differences were consistent with lowered fitness of males with a paternally inherited X-chromosome, expression differences suggested that this was due to deleterious maternal effects rather than imprinting. We conclude that imprinting is unlikely to resolve intralocus sexual conflict in Drosophila melanogaster. 18 samples were analyzed. There were 3 replicate populations within each of 3 treatments (Control, CDX, and MLX), and two males were analyzed from each population, for a total of 18 males.
