Differential regulation of protein kinase C isoenzymes during sphinganine potentiation of retinoic acid-induced granulocytic differentiation in human leukemia HL-60 cells.
Differential changes in the expression of PKC isoenzymes in the RA-induced differentiation were noted. As measured by Western blot analysis, our results indicated the expressions of PKC-alpha, and -beta isoenzymes decreased in the cell membrane but increased in the cytosol during the RA-induced granulocytic differentiation. The amounts of PKC-gamma, on the other hand, decreased in the cell membrane while there was no significant changes in the cytosol. Similarly, the expression of PKC-delta was not altered in the cytosol, but was slightly reduced during the SP enhancement of RA-induced differentiation. In contrast, there were virtually little changes in the expression of PKC-epsilon and -zeta in the cell membrane or in the cytosol during the RA-induced differentiation in the absence or presence of SP. Concomitant with the decreased total PKC activity, there was a decline in the generation of sn-1,2-diacylglycerol (DAG) during the RA-induced differentiation. SP, enhancing the RA-induced differentiation, also potentiated the decrease of DAG content.
Yung
B Y
BY
Department of Pharmacology, Chang Gung Medical College, Taiwan, Republic of China.
Hui
E K
EK
D015153:Blotting, Western; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D002460:Cell Line; D004075:Diglycerides / Q000378:metabolism; D004357:Drug Synergism; D004591:Electrophoresis, Polyacrylamide Gel; D006098:Granulocytes / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology; D006801:Humans; D007527:Isoenzymes / Q000302:isolation & purification / Q000378:metabolism*; D015473:Leukemia, Promyelocytic, Acute; D011493:Protein Kinase C / Q000302:isolation & purification / Q000378:metabolism*; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000494:pharmacology; D014212:Tretinoin / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D004075:Diglycerides; D007527:Isoenzymes; D014212:Tretinoin; D011493:Protein Kinase C; D013110:Sphingosine; C005682:safingol