Recent advances have started to elucidate the developmental functions and biochemistry of
Eph receptor tyrosine kinases and their membrane-bound ligands, ephrins. Interactions
between these molecules are promiscuous, but they largely fall into two groups: EphA
receptors bind to GPI-anchored ephrin-A ligands, while EphB receptors bind to ephrin-B
proteins that have a transmembrane and cytoplasmic domain. Remarkably, ephrin-B
proteins transduce signals, such that bidirectional signaling can occur upon interaction with …