16-P009 Wtip regulates the formation of multiple ciliated cells in the zebrafish pronephros

septum formation. Migration assays performed on primary cell cultures of myofibroblasts from wild type and Rfx3 / lungs show that Rfx3 / myofibroblasts loose their capacities to respond to environmental factors as guidance cues. We are currently dissecting the signaling cascades that are impaired in Rfx3-deficient myofibroblasts. In conclusion, RFX3 regulates primary ciliary growth and governs myofibroblast differentiation program in the developing lungs. Our work therefore suggests a novel function of primary cilia during lung development in vivo.