Project description:Two-dimensional patterning of the follicular epithelium in Drosophila oogenesis is required for the formation of three-dimensional eggshell structures. Our analysis of a large number of published gene expression patterns in the follicle cells suggests that they follow a simple combinatorial code based on six spatial building blocks and the operations of union, difference, intersection, and addition. The building blocks are related to the distribution of inductive signals, provided by the highly conserved epidermal growth factor receptor and Decapentaplegic (DPP) pathways. We demonstrate the validity of the code by testing it against a set of patterns obtained in a large-scale transcriptional profiling experiment. Using the proposed code, we distinguish 36 distinct patterns for 81 genes expressed in the follicular epithelium and characterize their joint dynamics over four stages of oogenesis. The proposed combinatorial framework allows systematic analysis of the diversity and dynamics of two-dimensional transcriptional patterns and guides future studies of gene regulation. Keywords: EGFR, BMP, gain/loss-of-function RNA was isolated from hand dissected, stage 9-10 egg chambers. Five genetic backgrounds were profiled including: wild type, EGFR gain of function, EGFR loss of function, BMP gain of function, and BMP loss of function. Three biological replicates were hybridized for each pathway perturbation. The samples were split across two rounds of hybridization. Each round of hybridizations included three biological replicates for wild type: The first round included EGFR gof, EGFR lof, BMP gof, and wild type controls A1-A3 (GSM313514-16). For these 12 arrays the extraction, labeling, and hybridization steps were done in parallel. The second round included the BMP lof and wild type controls B1-B3 (GSM313517-19). For these 6 arrays, the extraction, labeling, and hybridization steps were done in parallel.
Project description:We recently identified a missense mutation in Nucleoporin107 (Nup107; D447N) underlying XX-ovarian-dysgenesis (XX-OD), a disorder characterized by underdeveloped and dysfunctional ovaries. Specific knockdown of Nup107 in the somatic gonadal cells and moreover, modelling of the human mutation in Drosophila result in ovarian-dysgenesis-like phenotypes in female flies. The aberrant phenotypes in larval and adult ovaries compromised for Nup107 are associated with hyperactivation of BMP signalling. Transcriptomic analysis identified the somatic sex-determination gene Doublesex (dsx) and the extracellular metalloprotease AdamTS-A as targets of Nup107. Either loss or gain of Dsx in the gonadal soma is sufficient to respectively mimic or rescue the phenotypes induced by Nup107 loss. Furthermore, adamTS-A is transcriptionally regulated by Dsx, and its knockdown in the somatic gonad hyperactivates BMP signaling and to a large extent recapitulates loss of Nup107 phenotypes. Thus, Dsx acts downstream of Nup107 to impact female germline stem cells via sex-specific modulation of the BMP pathway.
Project description:We designed this experiment to investigate the transcriptional changes in gonads as a result of sex transformation. Here we performed transcriptional profiling of the ovary transformed into testis from the tra loss of function (XX_tra_lof), testis transformed into ovary from the tra gain of function (XY_tra_gof) and ovary transformed into testis in dsxM gain of function (XX_DsxM_gof/lof) Drosophila melanogaster third instar larvae in biological quadruplicates. In addition, as controls we sequenced ovaries and testes from the female and male wildtype larvae respectively. We constructed polyA+ libraries of the gonads, cleaned off the fatbody and performed 50 bp, stranded single-end RNA-Seq.
Project description:Two-dimensional patterning of the follicular epithelium in Drosophila oogenesis is required for the formation of three-dimensional eggshell structures. Our analysis of a large number of published gene expression patterns in the follicle cells suggests that they follow a simple combinatorial code based on six spatial building blocks and the operations of union, difference, intersection, and addition. The building blocks are related to the distribution of inductive signals, provided by the highly conserved epidermal growth factor receptor and Decapentaplegic (DPP) pathways. We demonstrate the validity of the code by testing it against a set of patterns obtained in a large-scale transcriptional profiling experiment. Using the proposed code, we distinguish 36 distinct patterns for 81 genes expressed in the follicular epithelium and characterize their joint dynamics over four stages of oogenesis. The proposed combinatorial framework allows systematic analysis of the diversity and dynamics of two-dimensional transcriptional patterns and guides future studies of gene regulation. Keywords: EGFR, BMP, gain/loss-of-function
Project description:We characterized changes of transposon and mRNA expressions in armi, rhino ,aub, ago3 mutants with respect to wild type using Affy tiling array. In most of these mutants, mRNA expressions were mostly unchanged but increased expressions was observed for many transposons indicating the role of these proteins in silencing transposons in Drosophila ovaries Keywords: Tiling array transcriptome profiling
Project description:In Drosophila, efferent neurons gain access to a target-derived BMP signal in the periphery that is required for differentiation and/or synaptic growth and neurotransmission. This requires transcriptional activity of the BMP-activated Smad transcription factors, but the Smad-bound enhancers and BMP-regulated effector genes they control remain unidentified. In the absence of insight into how BMP signaling controls these fundamental aspects of neuronal development and function, here we test whether Smads act directly at widely-deployed archetypal Smad-binding motifs to directly co-regulate batteries of BMP-responsive genes. To target these motifs for analysis, we employed a bioinformatics approach to identify candidate motifs conforming to the consensus 15bp BMP-Activation Element (BMP-AE). After filtering for high conservation and proximity to neuronally-expressed genes, we prioritized 62 BMP-AEs for analysis. Testing the in vivo enhancer activity of 58 genomic fragments containing these BMP-AEs in transgenic reporters, we show that 61% are functional BMP enhancers in diverse motoneuron and neuropeptidergic neuronal populations, and that the BMP-AE motif itself is required for activity. Moreover, 60% of these functional BMP-AEs were located within 20kb of at least one BMP activated gene, as identified by RNAseq analysis. Finally, we show that the BMP-AE motif plays a conserved activator function in the vertebrate nervous system, by electroporation in the developing chick neural tube. Our results provide evidence that BMP signaling controls neuronal development and function by directly coordinating networks of genes through widespread deployment of conserved, consensus Smad-binding motifs.
Project description:Nuclear lamina (NL) contributes to tissue homeostasis. In Drosophila, compromised NL blocks differentiation and causes loss of germline stem cells (GSCs) due to activation of the Chk2 checkpoint kinase. Checkpoint activation occurs upon loss of the NL protein Drosophila emerin or its partner Barrier-to-autointegration factor (BAF). As NL has long been thought to interact with specific genomic loci and regulate transcription, we examined transcriptional changes in emerin-/- and baf KD ovaries. We found thousands of genes are mis-regulated upon loss of emerin or BAF in GSCs. Remarkably, more than 90% of mis-regulated genes are shared between emerin-/- and baf KD. Finally, we show that transcriptional changes are downstream of Chk2 activation, as transcription are restored in chk2, emerin double mutant ovaries.
Project description:Affinity Purification Mass Spectrometry (AP-MS) of Drosophila ovaries expressing an H2A.Z-FlagHA transgene to identify interacting partners of H2A.Z to elucidate potential maternally supplied histone chaperones that deposit H2A.Z on the transcription start site (TSS).