Understanding thrombocytopenia: physiological role of microRNA in survival of neonatal megakaryocytes.

Neonates are predisposed to developing thrombocytopenia and neonates are affected by megakaryocytic disorders such as thrombocytopenia with absent radius syndrome and transient myeloproliferative disorder. Small double stranded non-coding microRNAs (miRNAs) have been shown to crucially involve in the regulation of stem-cell differentiation in normal as well as malignant haematopoiesis. The regulatory mechanism in developmental megakaryocytopoiesis and role of miRNAs in biological differences between adult and neonatal megakaryopoiesis is unknown. Here in we compared miR-99a levels in megakaryocytes (MKs) derived from cord blood (CB) and peripheral blood using qRT-PCR. CTDSPL is predicted as potential target of miR-99a and was confirmed by western blot. CTDSPL is shown to involve in regulation of cell growth and differentiation and exhibits tumor suppressor activity. We believe that miR-99a regulates CTDSPL, which induces the G1/S transition by increasing Cyclin expression and play a significant role in proliferation of CB-MKs.