PIPKIIα is widely expressed in hematopoietic-derived cells and may play a role in the expression of alpha- and gamma-globins in K562 cells

Characterized for the first time in erythrocytes, phosphatidylinositol phosphate kinases (PIP kinases) belong to a family of enzymes that generate various lipid messengers and participate in several cellular processes, including gene expression regulation. Recently, the PIPKII alpha gene was found to be differentially expressed in reticulocytes from two siblings with hemoglobin H disease, suggesting a possible relationship between PIPKII alpha and the production of globins. Here, we investigated PIPKII alpha gene and protein expression and protein localization in hematopoietic-derived cells during their differentiation, and the effects of PIPKII alpha silencing on K562 cells. PIPKII alpha silencing resulted in an increase in alpha and gamma globins and a decrease in the proliferation of K562 cells without affecting cell cycle progression and apoptosis. In conclusion, using a cell line model, we showed that PIPKII alpha is widely expressed in hematopoietic-derived cells, is localized in their cytoplasm and nucleus, and is upregulated during erythroid differentiation. We also showed that PIPKII alpha silencing can induce alpha and gamma globin expression and decrease cell proliferation in K562 cells.