['Tescalcin is an EF-hand calcium-binding protein that interacts with the Na+/H+ exchanger 1 (NHE1). Levay and Slepak recently proposed a role for tescalcin in megakaryopoiesis that was independent of NHE1 activity. Their studies using K562 and HEL cell lines, and human CD34+ hematopoietic stem cells suggested an essential role for tescalcin in megakaryocyte differentiation.', 'To study the role of tescalcin in megakaryocyte development using a murine model of megakaryopoiesis.', 'We generated a mouse with targeted disruption of tescalcin and investigated megakaryocyte development.', 'Tescalcin-deficient mice had a normal number of megakaryocytes and platelets. The morphology, polyploidization profile, and expression of Fli-1 in bone marrow-derived megakaryocytes were also normal.'] Is megakaryocyte development normal in mice with targeted disruption of Tescalcin?