Erythropoietin (Epo) elicits cell-specific responses upon interacting with its receptor EpoR. Activation of EpoR by Epo results in receptor homodimerization, which induces a cascade of signaling events.Epo is a major activator of the Ras/MAPK pathway. This activation is achieved via signaling through GRB2, SHC, GAB2 and the PTB domain containing proteins. GRB2 constitutively associates with SOS and binds to EpoR either via an interaction with GAB2 or by binding to EpoR-associated tyrosine-phosphorylated SHC...