Project description:Adult leg muscle precursors are associated to leg imaginal disc, here we provide bulk RNA sequecing of FACS sorted myoblasts from dissected imaginal leg discs at beginning of pupation.
Project description:The progenitors of Drosophila leg tendon are specified among leg disc epithelium during third larval instar. At the end of larval stages and beiginning of pupae formation, tendon cells invaginate and then collectively migrate to form a tube-shaped structure.
Project description:Although the majority of genomic binding sites for the insulator protein CTCF are constitutively occupied, a subset show variable occupancy. Such variable sites provide an opportunity to assess context-specific CTCF functions in gene regulation. Here we have identified a variably occupied CTCF site in the Ultrabithorax (Ubx) gene in Drosophila. This site is occupied in tissues where Ubx is active (third thoracic imaginal leg disc) but is not bound in tissues where the Ubx gene is repressed (first thoracic imaginal leg disc). Comparison of CTCF binding in T1 leg disc vs T3 leg disc in from 3rd instar larva
Project description:Although the majority of genomic binding sites for the insulator protein CTCF are constitutively occupied, a subset show variable occupancy. Such variable sites provide an opportunity to assess context-specific CTCF functions in gene regulation. Here we have identified a variably occupied CTCF site in the Ultrabithorax (Ubx) gene in Drosophila. This site is occupied in tissues where Ubx is active (third thoracic imaginal leg disc) but is not bound in tissues where the Ubx gene is repressed (first thoracic imaginal leg disc).
Project description:We report on changes in gene expression resulting from the ecdysone-directed broad-based transcriptional regulatory hierarchy in Drosophila melanogaster leg imaginal discs by comparing expression in white1118 third-instar larvae (-18 hrs relative to pupariation) and white prepupae (0 hrs) to examine the transcriptional effects of the late larval ecdysone pulse, as well comparing expression in white1118 and broad5 white prepupal leg imaginal discs to examine the transcriptional effects of the early ecdysone responder, broad. Using this approach, we were able to identify critical leg disc elongation genes that are differentially regulated in broad mutants
Project description:Regeneration of fragmented Drosophila imaginal discs occurs in an epimorphic manner, involving local cell proliferation at the wound site. Following disc fragmentation, cells at the wound site activate a restoration program through wound healing, regenerative cell proliferation and repatterning of the tissue. However, the interplay of signaling cascades, driving these early reprogramming steps, is not well understood. Here we profiled the transcriptome of regenerating cells in the early phase within twenty-four hours after wounding. We found that JAK/STAT signaling becomes activated at the wound site and promotes regenerative cell proliferation in cooperation with Wingless (Wg) signaling. In addition, we demonstrated that the expression of Drosophila insulin-like peptide 8 (dilp8), which encodes a paracrine peptide to delay the onset of pupariation, is controlled by JAK/STAT signaling in early regenerating discs. Our findings suggest that JAK/STAT signaling plays a pivotal role in coordinating regenerative disc growth with organismal developmental timing. In order to analyze transcriptome change in early regenerating imaginal disc, Drosophila prothorasic leg discs were fragmented (to anterior one-quarter or posterior three-quarters) and cultured ex vivo in adult fly abdomen. Regenerating cells in early regeneration phase (at 12 or 24 hours after wounding) were subjected to transcriptome profiling with Affymetrix microarrays. For control samples, the corresponding regions of uncut-cultured discs and uncut-uncultured discs were used.
Project description:Animal limb development relies on the establishment of organizing centers, which govern limb outgrowth and patterning by regulating the spatial and temporal expression of secreted signaling molecules. On a molecular level the establishment of organizing centers occurs via cis regulatory modules (CRMs), also known as transcriptional enhancers, that integrate upstream temporal and spatial inputs. We elucidated the mechanism that governs the establishment of an Epidermal Growth Factor Receptor (EGFR) organizing center (EOC) during leg development in Drosophila melanogaster. We find that EGFR activation occurs by sequential activation of the EGFR ligand Vein (Vn) and the EGFR ligand-processing protease Rhomboid (Rho), each through single CRMs. These CRMs integrate in a distinct manner inputs from the Wingless (Wg) and Decapentaplegic (Dpp) signaling pathways, and from the leg selector transcription factors Distal-less (Dll) and Sp1. Elimination of the vn (vnE) and rho (rhoE) EOC enhancers eliminates the expression of these genes in the center of the leg imaginal discs, respectively. A vnE rhoE double deficiency, but not single deletions, demonstrates an absolute requirement of these CRMs for specifying the most distal, but not more proximal, leg fates. In addition, the cis-regulatory logic of vnE and rhoE transcends the leg EOC developmental program, because genomic regions with similar inputs, based on predicted and genome-wide binding by the transcription factors that establish the EOC, faithfully predicts novel CRMs active in the distal leg. The combinatorial input of Wg, Dpp, Dll and Sp1 at these CRMs reveals a molecular signature for coordinating gene expression in the Drosophila leg that might be analogous to many other multi-cellular systems.