Erythropoietin (EPO) mediates its biologic actions in responsive cells
through the 78 kDa cell surface form of the EPO receptor. The biosynt
hesis, activations, and destruction of EPO receptors are described. Th
e binding of EPO to its receptor leads to the activation of a tyrosine
protein kinase(s) that results in the phosphorylation of the receptor
and other proteins.