Lymphocyte antigen receptor signal integration and regulation by the SHC adaptor

The Shc adaptor protein transduces signals from transmembrane receptors to the Has pathway of cell activation by providing binding sites for the recru itment to the submembrane compartment of the Grb2/Sos G-nucleotide exchange complex. The need for Shc in this process is however unclear since Grb2 ca n be recruited directly to phosphotyrosine containing membrane receptors th rough its src-homology-2 domain. Evidence from studies in lymphocytes indic ates that Shc is multifunctional and is involved in the integration of inde pendent signals to the Has pathway. Furthermore, Shc may be a key control p oint at which signaling can be modulated both by interfering signals and by feedback mechanisms. Here we review recent literature to support these fun ctions for Shc.