Regulation of Myeloid-Specific Calcium Binding Protein Synthesis by Cytosolic Protein Kinase C

• Published in: Journal of biochemistry (Tokyo) 1992-11, Vol.112 (5), p.624-630
• Main Authors: Koike, Tsuneaki, Harada, Naoki, Yoshida, Takeshi, Morikawa, Minoru
• Format: Article
• Language: English
• Subjects: 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; Analytical, structural and metabolic biochemistry; Animals; Binding and carrier proteins; Biological and medical sciences; Blotting, Northern; Calcitriol - pharmacology; Calcium-Binding Proteins - biosynthesis; Calgranulin A; Calgranulin B; Cell Differentiation - drug effects; Cytosol - enzymology; Electrophoresis, Polyacrylamide Gel; Enzyme-Linked Immunosorbent Assay; Fundamental and applied biological sciences. Psychology; Humans; Isoquinolines - pharmacology; Leukemia; Mice; Mice, Inbred BALB C; Piperazines - pharmacology; Protein Kinase C - antagonists & inhibitors; Protein Kinase C - metabolism; Proteins; RNA, Messenger - metabolism; Tetradecanoylphorbol Acetate - pharmacology; Transforming Growth Factor beta - metabolism; Tretinoin - pharmacology; Tumor Cells, Cultured
• ISSN: 0021-924X; 1756-2651
• DOI: 10.1093/oxfordjournals.jbchem.a123950

Two calcium binding proteins, MRP-8 and MRP-14, are specifically synthesized in human myeloid cells. This paper shows that Me2SO, all-trans-retinoic acid (RA) and la,25-dihydroxyvitamin D3 (1α,25(OH)2D3), bat not 12-O-tetradecanoyl phorbol-13-acetate (PMA) are potent inducers of MRP-8/14 protein complex in human leukemic cells. Transforming growth factor-β1 (TGF-β1) is shown to enhance the inductive effect of RA and la,25(OH)2D3. We have examined the possibility that MRP expression is regulated through the protein kinase pathway. Both cytosolic and membrane-bound protein kinase C (PKC) activities increased during differentiation by RA and lα,25(OH)2D3. PMA-treatment led to a decrease of cytosolic PKC activity and an increase of membrane-bound PKC activity in the presence of these differentiation inducers, while PMA alone resulted in low cytosolic and high membrane-bound PKC activities. PKC inhibitor H7 inhibited MRP synthesis in HL-60 cells treated with RA and 1α,25(OH)2D3. These results suggest that cytosolic PKC activity may be involved in a stimulatory pathway of MRP synthesis and that protein phosphorylation reactions may play important roles in MRP expression during myelocytic differentiation.