Hedgehog signaling and the axial patterning ofDrosophilawings

Abstract

Growth and cell fate in the anterior-posterior (A/P) axis of the developing wing of Drosophila melanogaster are controlled by a stripe of cells bisecting the axis called the A/P organizer. Hedgehog (Hh) signaling from posterior to anterior cells induces the organizer. Several Hh-responsive genes expressed by cells of the organizer mediate its patterning activity. The Hh-signaling pathway controls the post-translational modification of the transcription factor Cubitus-interruptus (Ci) and the resulting local activation of Ci is required for the correct location of the A/P organizer.

A Genetic Screen in Drosophila for Identifying Novel Components of the Hedgehog Signaling Pathway

“…In the absence of Hh, the full-length Ci protein (Ci-155) is degraded into a smaller, repressor form (Ci-75). The activation of Hh signaling inhibits this degradation and induces the stabilization and accumulation of Ci-155 in anterior cells along the A/P compartment boundary (Brook 2000). The upregulation Ci-155 can be detected with the rat monoclonal anti-2A1 (see Figure 6, A, C, D, partment that abuts the A/P boundary ( Figure 6, D-F).…”

“…Hh was low-threshold genes are expressed (see Brook 2000). The ability of Hh to induce differential responses can originally identified as a segment polarity gene in Drosophila where it is required for the patterning of the be partially explained by the dual activity of the zincfinger transcription factor Cubitus interruptus (Ci), the embryonic cuticle.…”

The bristle pattern development in Drosophila melanogaster: the prepattern and achaete-scute genes

“…At this stage, the cells differ in the amounts of some proteins, which later on determine the main stages in disc com partmentalization. These proteins include EN, DPP, Dis talless (DLL), Vestigial (VG), WG, and HH (Blair, 1995;Brook, 2000;Held, 2002;Hooper, Scott, 2005;Beira, Paro, 2016). Note that DPP, WG, and HH form a concentration gra dient, while the EN protein is confined to a narrow band with a width of one cell.…”

“…The dorsal disc region is determined by coexpression of the vg and ap genes and the ventral region, by expression of the gene wg. The regions where the genes determining compartments are expressed do not overlap and the corresponding boundaries are indentified as conditional anterior -posterior and dorsal -ventral axes of the disc (Brook, 2000;Delanoue et al, 2002).…”