Expression patterns of ShcD and Shc family adaptor proteins during mouse embryonic development.

The Src homology and collagen (Shc) proteins function as molecular adaptors in signaling pathways mediated by a variety of cell surface receptors. Of the four mammalian Shc proteins, ShcD is the least characterized. To this end, ShcD expression was documented and compared to that of other Shc family proteins. In the developing mouse embryo, expression of ShcD overlaps with that of other Shc proteins in the central nervous system, with specific distribution in post-mitotic neurons. In addition, robust ShcD expression is seen within differentiated epithelial cells of several organs, as well as in skeletal and cardiac muscle, and various tissues of neural crest origin. Interestingly, all Shc family members are expressed in hypertrophic chondrocytes, the first report of Shc protein expression in the developing skeleton. The unique tissue distribution patterns of Shc proteins likely contribute to their complex tissue-specific signaling functions during embryogenesis.