Human TPO

Thrombopoietin (Tpo) is a key regulator of megakaryocytopoiesis and thrombopoiesis. It is principally produced in the liver and is bound and internalized by the receptor Tpo R/c mpl. Defects in the Tpo Tpo R signaling pathway are associated with a variety of platelet disorders. The 353 amino acid (aa) human Tpo precursor is cleaved to yield the 332 aa mature protein. Tpo promotes the differentiation, proliferation, and maturation of MK and their progenitors. Tpo additionally promotes platelet production, aggregation, ECM adhesion, and activation. Aside from its hematopoietic effects, Tpo is expressed in the brain where it promotes the apoptosis of hypoxia sensitized neurons and inhibits neuronal differentiation by blocking NGF induced signaling _1-5_.