Identification of multiple PKC isoforms in Swiss 3T3 cells: differential down-regulation by phorbol ester.
The expression of members of the Ca2+ and phospholipid-dependent protein kinase (PKC) family were studied in murine Swiss 3T3 cells. In addition to PKC-alpha, the presence of immunoreactive PKC-delta, -epsilon, and zeta was detected. Treatment with 500 nM 12-0-tetradecanoylphorbol-13-acetate (TPA) led to the down-regulation of alpha, delta, and epsilon isoforms, but not that of zeta. Higher concentrations of TPA similarly had no effect on the level of PKC-zeta. In contrast to PKC-alpha, the membrane localization of PKC-delta, -epsilon, and -zeta was not enhanced by extraction in Ca(2+)-containing buffers, whereas acute TPA treatment increased membrane association of PKC-alpha, -delta, and -epsilon but not that of PKC-zeta.
Olivier
A R
AR
Protein Phosphorylation Laboratory, Imperial Cancer Research Fund, London, United Kingdom.
Parker
P J
PJ
D016475:3T3 Cells; D000818:Animals; D015153:Blotting, Western; D002460:Cell Line; D015536:Down-Regulation; D007527:Isoenzymes / Q000378:metabolism*; D051379:Mice; D011493:Protein Kinase C / Q000378:metabolism*; D013347:Subcellular Fractions / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
D007527:Isoenzymes; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate