PT - JOURNAL ARTICLE AU - Boyd, Andrew W. AU - Lackmann, Martin TI - Signals from Eph and Ephrin Proteins: A Developmental Tool Kit AID - 10.1126/stke.2001.112.re20 DP - 2001 Dec 11 TA - Science's STKE PG - re20--re20 VI - 2001 IP - 112 4099 - http://stke.sciencemag.org/content/2001/112/re20.short 4100 - http://stke.sciencemag.org/content/2001/112/re20.full SO - Sci. STKE2001 Dec 11; 2001 AB - Interactions between Eph receptors and their ligands the ephrin proteins are critically important in many key developmental processes. Emerging evidence also supports a role for these molecules in postembryonic tissues, particularly in pathological processes, including tissue injury and tumor metastasis. We review the signaling mechanisms that allow the 14 Eph and nine ephrin proteins to deliver intracellular signals that regulate cell shape and movement. What emerges is that the initiation of these signals is critically dependent on which Eph and ephrin proteins are expressed, the level of their expression, and, in some cases, which splice variants are expressed. Diversity at the level of initial interaction and in the downstream signaling processes regulated by Eph-ephrin signaling provides a subtle, versatile system of regulation of intercellular adhesion, cell shape, and cell motility.