Project description:These experiments measure genome-wide RNA Pol II binding in precisely staged wild-type embryos at five time points spanning the maternal to zygotic transition (nuclear cycles 12 through 14) of Drosophila melanogaster. In addition, RNA Pol II binding at nuclear cycle 13 is measured in embryos mutant for either mei-41/ATR or zelda. To correlate RNA Pol II binding with replication stress, genome-wide profiles of Replication protein A (70kDa subunit, RpA-70 EGFP) were generated in parallel with RNA Pol II for both wild-type and zelda at nuclear cycle 13.
Project description:In most embryos, the mid-blastula transition is a complex process featuring maternal RNA degradation, cell cycle pause, zygotic transcriptional activation and morphological changes. The nucleocytoplasmic (N/C) ratio has been proposed to control the multiple events at MBT. To understand the global transcriptional response to the changes of the N/C ratio, we profiled wild type and haploid embryos using cDNA microarrays at three developmental stages. Keywords: time course and different genotype
Project description:Transcriptional profiling of developmentally staged D. mel. Embryos for three genotypes: wild type, eve3 and ftz11 For additional information, please see Liu et al., 2009. Abstract: We constructed a large-scale functional network model in Drosophila melanogaster built around two key transcription factors involved in the process of embryonic segmentation. Analysis of the model allowed the identification of a new role for the ubiquitin E3 ligase complex factor SPOP. In Drosophila, the gene encoding SPOP is a target of segmentation transcription factors. Drosophila SPOP mediates degradation of the Jun-kinase phosphatase Puckered thereby inducing TNF/Eiger dependent apoptosis. In humans we found that SPOP plays a conserved role in TNF-mediated JNK signaling and was highly expressed in 99% of clear cell renal cell carcinoma (RCC), the most prevalent form of kidney cancer. SPOP expression distinguished histological subtypes of RCC and facilitated identification of clear cell RCC as the primary tumor for metastatic lesions. Keywords: 2 channel transcription timecourse
Project description:These experiments measure genome-wide RNA Pol II binding in precisely staged wild-type embryos at five time points spanning the maternal to zygotic transition (nuclear cycles 12 through 14) of Drosophila melanogaster. In addition, RNA Pol II binding at nuclear cycle 13 is measured in embryos mutant for either mei-41/ATR or zelda. To correlate RNA Pol II binding with replication stress, genome-wide profiles of Replication protein A (70kDa subunit, RpA-70 EGFP) were generated in parallel with RNA Pol II for both wild-type and zelda at nuclear cycle 13. Two replicates each for 5 time points for wild type RNA Pol II. Two replicates for mei-41 RNA Pol II, nuclear cycle 13. Two replicates for zelda RNA Pol II, nuclear cycle 13. Two replicates each for Rpa70-EGFP in wild-type or zelda, nuclear cycle 13, matched to the corresponding RNA Pol II sample.
Project description:In most embryos, the mid-blastula transition is a complex process featuring maternal RNA degradation, cell cycle pause, zygotic transcriptional activation and morphological changes. The nucleocytoplasmic (N/C) ratio has been proposed to control the multiple events at MBT. To understand the global transcriptional response to the changes of the N/C ratio, we profiled wild type and haploid embryos using cDNA microarrays at three developmental stages. Experiment Overall Design: For the diploid transcriptional profile, we prepared cDNA from hand selected wild-type embryos at cycle 13 interphase (15min after the nuclear division of cycle 12) and at early and late cycle 14 interphase (15min and 40 min after the nuclear division of cycle 13), respectively. For the haploid, cDNA was prepared from cycle 14 embryos (15min after the nuclear division of cycle 13) and early and late cycle 15 embryos (15min and 40 minutes after the nuclear division of cycle 14). The collection was designed in this way so that each cell cycle stage of the diploid has a counterpart stage with matched N/C ratio in the haploid (e.g. cycle 13 in the diploid has the same N/C ratio as cycle 14 in the haploid). In all experiments, the cell cycle progression was monitored by the Histone-GFP pattern. Triplicates of about 50 embryos each with right age were collected for each time point.
Project description:During animal development, a fertilized egg is initially under the control of maternal products and only starts zygotic transcription after several cell divisions. In animals such as Xenopus, zebrafish and Drosophila, a massive increase in zygotic transcription occurs during the mid-blastula transition (MBT), when cells shift from rapid, synchronous cell divisions without gap phases to prolonged asynchronous divisions. Before MBT, only a few so-called pre-MBT genes are expressed. How transcription is set up during these early stages is poorly understood. For example, paused RNA Polymerase (Pol II) is frequently found at developmental control genes in mammalian embryonic stem cells and Drosophila embryos but when Pol II pausing is first established in the embryo is unknown. We have analyzed the genome-wide Pol II occupancy during the maternal-to-zygotic transition in hand-staged Drosophila embryos. The results show that massive Pol II recruitment and pausing is established during MBT. The ~100 genes that are transcribed before MBT are particularly short, consistent with a need for rapid transcription during these early cell divisions. Remarkably, most of these genes are transcribed without Pol II pausing and this correlates with a TATA-enriched promoter type. This suggests that distinct strategies are used for activation in the early Drosophila embryo and this may reflect general dynamic properties of promoters used throughout development. Mnase-seq in staged Drosophila embryos