The relationship between human megakaryocyte nuclear DNA content and gene expression.

Increased platelet reactivity has been implicated in various vascular diseases. Since the protein content of platelets is determined mainly by the megakaryocyte, alterations in megakaryocyte mRNA expression may influence platelet protein content and therefore activity. In order to determine whether DNA content (ploidy) of a megakaryocyte influences its mRNA expression, we have developed a method to investigate the relationship between megakaryocyte ploidy and gene expression. By measuring the ploidy and mRNA expression in individual cells, we have shown that in the physiological state there is an increase in mRNA expression for beta-actin, glycoprotein IIb and neuropeptide Y with increase in ploidy and that this increase levels off at high ploidy values. This may have relevance in the understanding of platelet reactivity in pathological events.