09-P065 Tal1 regulates tight junction establishment during endocardial tube formation

extending and retracting numerous actin-rich protrusions during tubule morphogenesis. Interestingly, tubule morphogenesis fails in mutant embryos lacking tip cells and supports a role for tip cells during this phase of tubule development. Moreover, the tip cells make highly specific contacts with target tissues once tubule morphogenesis is complete and these persist during larval life, raising the intriguing possibility that tip cells may have additional post-embryonic roles. This data, together with previous studies in other systems, suggest that tip cell-driven morphogenesis may be a common feature during organogenesis of tubular networks.