Rhomboid 3 orchestrates Slit-independent repulsion of tracheal branches at the CNS midline

摘要: EGF-receptor ligands act as chemoattractants for migrating epithelial cells during organogenesis and wound healing. We present evidence that Rhomboid 3/EGF signalling, which originates from the midline of Drosophila ventral nerve cord, repels tracheal ganglionic branches prevents them crossing it. rho3 acts independently main repellent Slit, a different sub-population cells: VUM neurons. Expression dominant-negative Egfr or Ras induces crosses, whereas activation in leading cell branch can induce premature turns away midline. This suggests level intracellular rather than asymmetric receptor on surface, is an important determinant repulsion. propose provides necessary switch interpretation yet unknown function