Abundant Src Homology Protein

A signal transducing adaptor protein that links extracellular signals to the MAP Kinase Signaling System. Grb2 associates with activated Epidermal Growth Factor Receptor and Platelet-Derived Growth Factor Receptors via its SH2 DOMAIN. It also binds to and translocates the Son of Sevenless Proteins through its SH3 DOMAINS to activate Proto-Oncogene Protein p21(ras).