Alterations in protein kinase C type III-alpha during heat shock of rat embryo fibroblasts.
Heat shock treatment of rat embryo fibroblasts resulted in a 60% increase in cytosolic protein kinase C activity, in contrast to phorbol ester-induced translocation to the membrane. During reversal of the cells back to the normal temperature a decrease in cytosolic PKC activity was observed and paralleled by an increase in protamine kinase activity. Cell lysates prepared from heat shock-treated cells show a marked calcium/phospholipid-dependent phosphorylation of several endogenous PKC substrate proteins, while the 28-kDa stress protein was shown to be a PKC substrate. These cells express the TYPE III-alpha isoform of PKC and, thus, the alterations induced within cells exposed to hyperthermic treatment may reflect a functional significance with regard to the regulation of this specific isoform.
Wooten
M W
MW
Auburn University, Department of Zoology & Wildlife Science, Alabama 36849-5414.
D000818:Animals; D002460:Cell Line; D015180:Electrophoresis, Gel, Two-Dimensional; D006360:Heat-Shock Proteins / Q000378:metabolism*; D006358:Hot Temperature; D066298:In Vitro Techniques; D007527:Isoenzymes / Q000378:metabolism; D008970:Molecular Weight; D010750:Phosphoproteins / Q000737:chemistry / Q000378:metabolism*; D006656:Protamine Kinase; D011493:Protein Kinase C / Q000145:classification / Q000378:metabolism*; D011494:Protein Kinases / Q000378:metabolism; D051381:Rats
D006360:Heat-Shock Proteins; D007527:Isoenzymes; D010750:Phosphoproteins; D011494:Protein Kinases; D006656:Protamine Kinase; D011493:Protein Kinase C