Biopolym. Cell. 2002; 18(2):110-113.
Regulation of phosphatidylinositol 3-kinase activity during the megakaryocytic differentiation in human erythroleukemia cell line K562 induced by phorbol 12-myristate 13-acetate
1Ilnytska O. M., 1Oleksyn H. O., 1Kusen' S. J., 1Drobot L. B.
  1. Institute of Cell Biology, NAS of Ukraine
    14/16, Drahomanov Str., Lviv, Ukraine, 79005


An influence of phorbol 12-myristate 13-acetate (PMA) on the expression of p85α regulatory subunit of phosphatidylinositol (PI) 3-kinase, and on the PI 3-kinase activity during the megakaryocytic differentiation of K562 cells has been studied. It has been shown that the level of p85α expression does not change during 72 h culturing in both control and PMA-induced cells. At the same time, the coordinated changes of PI 3-kinase activity in differentiated cells in comparison with control ones suggest a differential role of PI 3-kinase signalling pathway in the proliferation regulation and in PMA-dependent megakaryocytic differentiation of K562 cells.


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