| Modification Notes |
The ErbB-2 receptor tyrosine kinase evolved as a shared coreceptor of all ErbB-specific growth factors and acts as a coordinator of a variety of biological signaling networks (1,2). ErbB-2 couples ErbB receptors to the migration/invasion machinery of carcinoma cells by employing adaptor proteins, such as p130CAS and c-CrkII, which regulate the actin-myosin cytoskeleton of migratory cells (2,3). ErbB-2 is expressed in basal cells of sqamous epithelia and is important in the morphogenesis and oncogenesis of secretory epithelia (4,5). In epithelia, ErbB-2 employs the adaptor protein ERBIN (ErbB-2 interacting protein), which functions in the localization and signaling of ErbB-2 (4). ERBIN contains a PDZ domain that directly and specifically interacts with ErbB-2, causing ERBIN and ErbB-2 to colocalize to the lateral membrane of intestinal epithelial cells (4). ERBIN provides further evidence to support the claim that the tumorigenic action of ErbB-2 may be attributed to its ability to acts as a shared signaling subunit, rather than functioning as a distinct receptor (5). |