※ Eph family introduction

    Eph receptor tyrosine kinases are known able to bind their ephrin ligands and act as key regulator of cell contact-dependent signaling and patterning. Eph kinase contains fourteen members which can further be classified into two subclasses A and B in human. EphA1-8 and Eph10 belong to subclass A, EphB1-4 and EphB6 belong to subclass B. Eph kinases consist of two regions: intracellular region and extracellular region. The extracellular part contains a globular ligand-binding domain, a cysteine-rich region and two fibronectin type III repeats. The intracellular part contains a short juxtamembrane region, a kinase catalytic domain, a sterile α motif (SAM) protein−protein interaction domain and a PDZ-binding motif. Eph/ephrin binding will lead to very diverse biological readouts including adhesion versus repulsion and increased versus decreased motility. Depending on the different cell type and context, the interaction will lead to different downstream signaling pathway. In addition, evidence shows that endocytosis of Eph/ephrin and associated tissue-specific effectors are essential for diverse biological roles and processes (1).

Reference
1. Pitulescu, M.E. and Adams, R.H. (2010) Eph/ephrin molecules--a hub for signaling and endocytosis. Genes Dev, 24, 2480-2492. PMID: 21078817