A recent report proposing that the dpp stripe (the main source of the protein dpp) is dispensable for Drosophila wing disc growth missed the critical role on growth due to imprecise spatial removal of dpp.
Cytonemes mediate, and are essential for, Wingless signaling from the Drosophila wing disc to disc-associated myoblasts and for Delta-Notch signaling from these myoblasts to the dorsal air sac primordium.
Experimental results in Drosophila support a model in which gene expression is fundamentally controlled by morphogens tuning the same transcription parameter for genes that are expressed in highly diverse patterns.
Hedgehog acts as a morphogen by regulating proteolytic processing and activation of full-length Ci/Gli transcriptional effectors but can pattern Drosophila wing discs normally in the absence of regulated proteolytic processing.
A novel role of endosomal machineries retromer and ESCRT in membrane delivery of Drosophila septate junction components is required for maintenance of junction integrity and epithelial barrier function.
Delivery of Hedgehog, Decapentaplegic and Wingless to target cells in the Drosophila wing imaginal disc is regulated in both amount and destination, and is not dependent on constitutive release or uptake from a common pool.
The reduced ability of Drosophila imaginal discs to regenerate as they mature can be explained by the silencing of damage-responsive enhancers that regulate expression of genes required for regeneration.