Grb2 mediates the EGF-dependent activation of guanine nucleotide exchange on Ras

Overexpression of Grb2 increases guanine-nucleotide exchange rate by working up a complex with the ligand-activated receptor. This coupling regulates tyrosine kinase that modulates Ras activity and mitogen-activated protein kinase. The ability of Grb2 to enhance Ras activity by facilitating guanine-nucleotide exchange rate is observed as a conserved mechanism that developed to advance receptor signals to Ras. Translocation can bond receptor activation to undiminished exchange factor activity, by transporting the factor to the subcellular compartment.