Figure 2.

Shc acts as a bridge connecting the extracellular signal and the different intracellular signalling pathways. Shc is recruited by activated cell surface receptors or integrins. Shc can then be phosphorylated either by receptor tyrosine kinases (EGFR) or cytosolic tyrosine kinases (Fyn, a protein of the Src family). Phosphorylated Shc can then interact with Grb2, leading to the activation of different pathways such as MAPK, PI3K/Akt and RhoA via the activation of Ras. Therefore, Shc proteins trigger different intracellular cascades, resulting in various cellular responses (adapted from Zhu and Parada, 2002).