ADDITION OF PHOSPHATIDYLCHOLINE-PHOSPHOLIPASE-C INDUCES CELLULAR REDISTRIBUTION AND PHOSPHORYLATION OF PROTEIN-KINASE-C-ZETA IN C-6 GLIAL-CELLS

Phosphatidylcholine breakdown has been shown to play a critical role i n signal transduction involving generation of a number of second messe ngers [Exton, J.H., Biochim. Biophys. Acta, 1212 (1994) 26-42]. In the present report we demonstrate by immunofluorescence that short-treatm ent of C6 glial cells with phosphatidylcholine-hydrolyzing phospholipa se C (PC-PLC), changes the intracellular localization of protein kinas e C (PKC) zeta from the cytoplasm to a perinuclear region, Western blo t analysis also showed a redistribution of PKC zeta after incubation o f cells with PC-PLC. To test whether these changes were accompanied by an activation of the enzyme, we measured the extent of phosphorylatio n of PKC zeta by immunoprecipitation from P-32-labelled cells, Short-t reatment with PC-PLC resulted in enhanced phosphorylation of the highe r Mr PKC zeta in C6 glial cells.