Xenopus embryos have an `odd man out' of nodal-related proteins– Xnr3. It is structurally different to other Xnrs, and, uniquely among them, induces cellular finger-like protrusions when ectopically expressed. This led Janet Heasman and colleagues to investigate the role of Xnr3in convergent extension movements during embryogenesis with morpholino oligos. They report, on p. 2199, that Xnr3– embryos have gastrulation and neurulation defects, and that Xnr3– cells fail to undergo convergent extension movements in gastrulae explants. Xnr3 requires the FGF receptor FGFR1 to induce these cell elongation movements, and also interacts synergistically with FRL1 (an FGFR-binding, EGF-CFC protein), indicating that Xnr3 regulates cell movement through FGFR signalling. Importantly, because Xnr3 is a target of the maternal Wnt/β-catenin pathway, these findings link the allocation of early cell fate by this pathway to the subsequent movement of cells from the organizer.

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