| Modification Notes |
Thrombopoietin (TPO or THPO), also known as c-Mpl ligand (c-Mpl L), is a cytokine that plays a central role in megakaryopoiesis by influencing the development and maturation of megakaryocytes and platelet production from hematopoietic stem cells (1,2). TPO exerts its biological effects through the TPO receptor, c-Mpl (3). c-Mpl is a member of the cytokine receptor superfamily, and its expression is restricted to hematopoietic tissues and cells, such as bone marrow, spleen, fetal liver and CD34+ cells (3). Stimulation of c-Mpl with TPO results in the activation of the Janus tyrosine kinase family members, Tyk 2 and JAK2, which in turn phosphorylate Stat5 and Stat3, causing their nuclear translocation and the transcription of Stat responsive genes (4,5). Mutations in c-Mpl have been implicated as the cause of certain human disorders, including congenital amegakaryocytic thrombocytopenia (CAMT) and thrombo- cytopenia with absent radii (TAR) syndrome (6,7). |