Project description:MicroRNAs detected in Drosophila melanogaster unfertilized eggs Bloomington w[1118] flies were kept at 25ºC on cornmeal based media, with 12 hours light/dark cycles. Virgin females were sorted at the pupae stage to avoid any unwanted fertilization. In a population cage I let 80-100 females to lay eggs in apple juice agar plates for 8 hours, collecting 1 hour after dawn. Eggs were collected with a sieve and washed with saline solution. Small RNA was size selected and sequenced.
Project description:This SuperSeries is composed of the following subset Series: GSE3286: Drosophila Life Cycle GSE3287: Unfertilized eggs GSE3288: Eyes absent mutant adults Abstract: Molecular genetic studies of Drosophila melanogaster have led to profound advances in understanding the regulation of development. Here we report gene expression patterns for nearly one-third of all Drosophila genes during a complete time course of development. Mutations that eliminate eye or germline tissue were used to further analyze tissue-specific gene expression programs. These studies define major characteristics of the transcriptional programs that underlie the life cycle, compare development in males and females, and show that large-scale gene expression data collected from whole animals can be used to identify genes expressed in particular tissues and organs or genes involved in specific biological and biochemical processes. Refer to individual Series
Project description:Using a tiled whole-genome microarray, we found that 58.2% of Tribolium castaneum genes are maternally loaded into eggs. Comparison of known Drosophila melanogaster maternal genes to our results showed widespread conservation of maternal function with T. castaneum. We also found many T. castaneum genes with previously identified gender or tissue specific expression were also maternally loaded into eggs. The microarray design also allowed the detection of 2315 and 4060 novel transcriptionally active regions greater in length than 100 bp in unfertilized and fertilized T. castaneum eggs, respectively. The primary objective of this study was to identify expressed regions of the Tribolium castaneum genome in unfertilized and fertilized eggs using a whole-genome tiled microarray.
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.
Project description:Early embryogenesis is a unique developmental stage where genetic control of development is handed off from mother to zygote. Yet the contribution of this transition to the evolution of gene expression is poorly understood. Here we study two aspects of gene expression specific to early embryogenesis in Drosophila: sex-biased gene expression prior to the onset of canonical X chromosomal dosage compensation, and the contribution of maternally supplied mRNAs. We sequenced mRNAs from individual unfertilized eggs, precisely staged and sexed blastoderm embryos and compared levels between D. melanogaster, D. yakuba, D. pseudoobscura and D. virilis. First, we find that mRNA content is highly conserved for a given stage and that studies relying on pooled embryos may systematically overstate the degree of gene expression divergence. Unlike studies done on larvae and adults, where most species show a larger proportion of genes with male-biased expression, we find that transcripts in Drosophila embryos are largely female-biased in all species, likely due to incomplete dosage compensation prior to the activation of the canonical dosage compensation mechanism. The divergence of sex-biased gene expression across species is observed to be often due to a decrease of expression, the most drastic example of which is the overall reduction of male expression from the neo-X chromosome in D. pseudoobscura, leading to a pervasive female-bias on this chromosome. We see no evidence for a faster evolution of expression on the X chromosome in embryos (no “faster X” effect), unlike in adults and contrary to a previous study on pooled non-sexed embryos. Finally, we find that most genes are conserved in regard to their maternal or zygotic origin of transcription, and present evidence that differences in maternal contribution to the blastoderm transcript pool may be due to species-specific divergence of transcript degradation rates We sequenced mRNA from D. melanogaser, D. yakuba, D. pseudoobscura and D. virilis single unfertilized eggs (1 to 2 per species) and from both single female and male embryos (3 per sex per species).