D-Eph-ective endocytosis disrupts topographic mapping

Since the discovery of the ephrin/Eph family of axon guidance molecules in the early '90s, research has often uncovered rather surprising aspects of their biology (Pasquale, 2008). A paper in this issue of The EMBO Journal provides further, novel insights into ephrin/Eph function. Here, the Park lab demonstrates the importance of Eph/ephrin endocytosis for retinotectal mapping, an interesting-though not unexpected-finding in itself. However, the surprise comes with their demonstration that endocytosis of the Eph/ephrin complex into neurons of the target structure, rather than into the retinal axons themselves, is of critical importance.