Erythropoietin

Erythropoietin, also known as erythropoetin or erthropoyetin (/ɨˌrɪθrɵˈpɔɪ.ɨtɨn/, /ɨˌrɪθrɵˈpɔɪtən/, and /ɨˌriːθrɵ-/) or EPO, is a glycoprotein hormone that controls erythropoiesis, or red blood cell production. It is a cytokine (protein signaling molecule) for erythrocyte (red blood cell) precursors in the bone marrow. Human EPO has a molecular weight of 34,000.