Protein kinase C zeta isoform is critical for mitogenic signal transduction.
The requirement of protein kinase C zeta (zeta PKC) for maturation of X. laevis oocytes in response to insulin, p21ras, and phosphatidylcholine-hydrolyzing phospholipase C has recently been shown. Here we present experimental evidence demonstrating that activation of zeta PKC is not only necessary but also sufficient by itself to activate maturation in oocytes and to produce deregulation of growth control in mouse fibroblasts. Furthermore, by using a dominant kinase-defective mutant of zeta PKC, we confirm that this kinase is required for mitogenic activation in oocytes and fibroblasts. These results permit us to propose zeta PKC as a critical step downstream of p21ras in mitogenic signal transduction.
Berra
E
E
Centro de Biología Molecular, Universidad Autonoma de Madrid, Canto Blanco, Spain.
Diaz-Meco
M T
MT
Dominguez
I
I
Municio
M M
MM
Sanz
L
L
Lozano
J
J
Chapkin
R S
RS
Moscat
J
J
D016475:3T3 Cells; D000595:Amino Acid Sequence; D000818:Animals; D001409:Bacillus cereus / Q000201:enzymology; D001483:Base Sequence; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004261:DNA Replication / Q000187:drug effects; D005260:Female; D005822:Genetic Vectors; D006133:Growth Substances / Q000494:pharmacology; D007328:Insulin / Q000494:pharmacology; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D009865:Oocytes / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D010766:Phosphorylation; D010957:Plasmids; D006656:Protamine Kinase / Q000494:pharmacology; D011493:Protein Kinase C / Q000235:genetics / Q000378:metabolism*; D016283:Proto-Oncogene Proteins p21(ras) / Q000378:metabolism; D012313:RNA / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D014162:Transfection; D010738:Type C Phospholipases / Q000302:isolation & purification / Q000494:pharmacology; D014982:Xenopus laevis
D006133:Growth Substances; D007328:Insulin; D007527:Isoenzymes; D009838:Oligodeoxyribonucleotides; D012313:RNA; D006656:Protamine Kinase; D011493:Protein Kinase C; D010738:Type C Phospholipases; D016283:Proto-Oncogene Proteins p21(ras)