First published online July 19, 2004
Development 131, 1504e (2004)
© The Company of Biologists Limited
Repulsed but not by Slit
During the morphogenesis of the Drosophila embryonic respiratory
(tracheal) system, epithelial cells form a branched, tubular network that
extends along stereotyped paths towards specific target tissues. Gallio et al.
now report that Rhomboid 3 (Rho3) stops tracheal ganglionic branches (GBs)
crossing the midline of the ventral nerve cord (VNC) in Drosophila
(see p. 3605).
Previous genetic analyses have uncovered several factors that guide the
migration of the GBs, which provide oxygen to the VNC, including Slit, the
main repulsive cue for axons at the midline. To identify additional factors,
the researchers screened a collection of P-element mutant flies for GB
pathfinding phenotypes. They report that Rho3, an intramembrane protease that
activates epidermal growth factor receptor (Egfr) ligands, guides GBs
independently of Slit, and propose that Rho3 activates one or more Egfr
ligands, which then repel migrating GBs from the VNC midline.
Related articles in Development:
- Rhomboid 3 orchestrates Slit-independent repulsion of tracheal branches at the CNS midline
- Marco Gallio, Camilla Englund, Per Kylsten, and Christos Samakovlis
Development 2004 131: 3605-3614.
[Abstract]
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