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Cross-talk between protein kinase C-alpha (PKC-alpha) and -delta (PKC-delta): PKC-alpha elevates the PKC-delta protein level, altering its mRNA transcription and degradation.
- Source :
-
Biochemistry [Biochemistry] 1998 Apr 21; Vol. 37 (16), pp. 5558-65. - Publication Year :
- 1998
-
Abstract
- Studies utilizing the overexpression of individual isoforms indicated that both PKC-alpha and -delta promote a number of biological effects, including inhibition of DNA synthesis associated with rearrangements of the actin cytoskeleton in the murine B-cell lymphoma (Baf3), differentiation of the murine promyelocyte line 32D, and activation of MAP kinase in CHO fibroblasts. We postulated that these results reflect some form of cross-regulation between PKC-alpha and -delta rather than their functional redundancy. In this report, we show that overexpression of PKC-alpha in Baf3 and 32D leads to an elevation of the endogenous PKC-delta mRNA and protein levels. The elevated steady-state PKC-delta mRNA level results from a combination of increased PKC-delta transcription and mRNA stability. Upregulation of PKC-delta mRNA by PKC-alpha occurs even after a selective depletion of the PKC-delta protein. In addition, phorbol ester-induced elevation of PKC-delta mRNA and protein levels can be prevented by the PKC inhibitor GF109203X, an indication of the requirement for PKC kinase activity. Inhibition of new protein synthesis by cycloheximide showed that upregulation of PKC-delta mRNA, as opposed to delayed downregulation of the PKC-delta protein, is primarily responsible for the accumulation of this isoform by PKC-alpha. In parental Baf3 and 32D cells and PKC-alpha overexpressers, PKC-alpha and PKC-delta are uniquely involved in cross-regulation, while PKC-epsilon, PKC-eta, and PKC-mu are not.
- Subjects :
- Animals
Enzyme Activation drug effects
Enzyme Activation genetics
Enzyme Stability drug effects
Enzyme Stability genetics
Indoles pharmacology
Isoenzymes biosynthesis
Isoenzymes physiology
Leukemia, Promyelocytic, Acute
Lymphoma, B-Cell
Maleimides pharmacology
Mice
Protein Kinase C biosynthesis
Protein Kinase C physiology
Protein Kinase C-alpha
Protein Kinase C-delta
Tetradecanoylphorbol Acetate pharmacology
Tumor Cells, Cultured
Up-Regulation drug effects
Up-Regulation genetics
Isoenzymes genetics
Isoenzymes metabolism
Protein Kinase C genetics
Protein Kinase C metabolism
RNA, Messenger metabolism
Transcription, Genetic drug effects
Subjects
Details
- Language :
- English
- ISSN :
- 0006-2960
- Volume :
- 37
- Issue :
- 16
- Database :
- MEDLINE
- Journal :
- Biochemistry
- Publication Type :
- Academic Journal
- Accession number :
- 9548940
- Full Text :
- https://doi.org/10.1021/bi9731807