Learn More
In the wing imaginal disc, the decapentaplegic (dpp) gene is expressed in a stripe of anterior cells near the anterior-posterior compartment boundary, and it is required solely in these cells for the entire disc to develop. In some viable segment polarity mutants, alterations in dpp expression have been demonstrated that correlate with changes in wing(More)
In the Drosophila wing imaginal disc, the Hedgehog (Hh) signal molecule induces the expression of decapentaplegic (dpp) in a band of cells abutting the anteroposterior (A/P) compartment border. It has been proposed that Dpp organizes the patterning of the entire wing disc. We have tested this proposal by studying the response to distinct levels of ectopic(More)
The genes decapentaplegic (dpp) and wingless (wg), which encode secreted factors of the TGF-beta and Wnt families, respectively, are required for the proper development of the imaginal discs. The expression of these genes must be finely regulated since their ectopic expression induces overgrowth and pattern alterations in wings and legs. Genes like patched(More)
The adult Drosophila wing (as the other appendages) is subdivided into anterior and posterior compartments that exhibit characteristic patterns. The engrailed (en) gene has been proposed to be paramount in the specification of the posterior compartment identity. Here, we explore the adult en function by targeting its expression in different regions of the(More)
The patterning of cells in insect segments requires the exchange of information between cells, which in Drosophila depends on the activity of members of the segment-polarity class of genes. Here we report the molecular characterization of one such gene, patched. We find that patched encodes a large protein with several possible membrane-spanning domains and(More)
The Hedgehog (Hh) family of signaling molecules function as organizers in many morphogenetic processes. Hh signaling requires cholesterol in both signal-generating and -receiving cells, and it requires the tumor suppressor Patched (Ptc) in receiving cells in which it plays a negative role. Ptc both blocks the Hh pathway and limits the spread of Hh. Sequence(More)
 The genital disc of Drosophila, which gives rise to the genitalia and analia of adult flies, is formed by cells from different embryonic segments. To study the organization of this disc, the expressions of segment polarity and homeotic genes were investigated. The organization of the embryonic genital primordium and the requirement of the engrailed and(More)
Mouse tumors induced by gamma radiation are a useful model system for oncogenesis. DNA from such tumors contains an activated K-ras oncogene that can transform NIH 3T3 cells. This report describes the cloning of a fragment of the mouse K-ras oncogene containing the first exon from both a transformant in rat-2 cells and the brain of the same mouse that(More)
The abdominal-A (abd-A) gene of Drosophila specifies abdominal segments two through eight (A2-A8). We have found that the uniform expression of the abd-A protein under heat shock control transforms embryonic segments anterior to the abd-A domain into an abdominal segment of the A2-A6 type. Posterior abdominal segments and telson undergo little or no(More)
In Drosophila, the homeotic gene Distal-less (Dll) has a fundamental role in the establishment of the identity of ventral appendages such as the leg and antenna. This study reports the expression pattern of Dll in the genital disc, the requirement of Dll activity for the development of the terminalia and the activation of Dll by the combined action of the(More)