Phospholipid metabolism in bradykinin-stimulated human fibroblasts. I. Biphasic formation of diacylglycerol from phosphatidylinositol and phosphatidylcholine, controlled by protein kinase C

A protein of Mr approximately 120,000, related to the human erythrocyte membrane skeletal protein alpha-adducin, has been identified by immunological criteria in human fibroblasts. Using similar methods, beta-adducin (an Mr approximately 110,000 protein that forms a dimeric complex with alpha-adducin in the erythrocyte) is not present in fibroblasts. Subcellular distribution studies reveal that fibroblast alpha-adducin is largely associated with the particulate fraction and is most effectively solubilized from that fraction by a combination of nonionic detergent and high salt. Immunocytochemistry of quiescent fibroblasts shows that alpha-adducin is clustered in large perinuclear arrays that may correspond to vesicular structures; weak staining was also found in the sub-plasma membrane region. As in erythrocytes, the phosphorylation of fibroblast alpha-adducin is elevated on exposure of cells to phorbol esters that activate protein kinase C (PK-C). In addition, various mitogens such as serum, bradykinin and vasopressin also stimulate alpha-adducin phosphorylation by a PK-C-dependent pathway. The elevation in alpha-adducin phosphorylation is maintained for up to 30 min after mitogen addition. Peptide maps of phospho-alpha-adducin from both fibroblasts and erythrocytes after PK-C-mediated phosphorylation showed multiple phosphorylated peptides but with dissimilar migration patterns, suggesting divergence of structure around the phosphorylation sites. Adducin appears to play an important role in the regulation of spectrin-actin interactions in the red cell and may play a role in cytoskeletal function in the fibroblasts.

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Comparative effects of polymyxin B, phorbol ester and bryostatin on protein phosphorylation, protein kinase C translocation, phospholipid metabolism and differentiation of HL60 cells

Biochemical and Biophysical Research Communications ◽

10.1016/0006-291x(87)90712-1 ◽

1987 ◽

Vol 146 (1) ◽

pp. 208-215 ◽

Cited By ~ 37

Author(s):

Zoltan Kiss ◽

Eva Deli ◽

Peggy R. Girard ◽

George R. Pettit ◽

J.F. Kuo

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Protein Phosphorylation ◽

Phorbol Ester ◽

Polymyxin B ◽

Phospholipid Metabolism ◽

Hl60 Cells ◽

Kinase C

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Insulin generates free radicals in human fibroblasts ex vivo by a protein kinase C-dependent mechanism, which is inhibited by pravastatin

Free Radical Biology and Medicine ◽

10.1016/j.freeradbiomed.2006.04.015 ◽

2006 ◽

Vol 41 (3) ◽

pp. 473-483 ◽

Cited By ~ 16

Author(s):

G CEOLOTTO ◽

I PAPPARELLA ◽

L LENZINI ◽

M SARTORI ◽

M MAZZONI ◽

...

Keyword(s):

Protein Kinase C ◽

Free Radicals ◽

Protein Kinase ◽

Ex Vivo ◽

Human Fibroblasts ◽

Kinase C ◽

Dependent Mechanism

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High glucose-induced growth factor resistance in human fibroblasts can be reversed by antioxidants and protein kinase C-inhibitors

Cell Biochemistry and Function ◽

10.1002/(sici)1099-0844(199709)15:3<197::aid-cbf740>3.0.co;2-7 ◽

1997 ◽

Vol 15 (3) ◽

pp. 197-201 ◽

Cited By ~ 45

Author(s):

Karin Hehenberger ◽

Anders Hansson

Keyword(s):

Protein Kinase C ◽

Growth Factor ◽

Protein Kinase ◽

High Glucose ◽

Human Fibroblasts ◽

Protein Kinase C Inhibitors ◽

Kinase C

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Inhibition of myogenesis by the H-ras oncogene: implication of a role for protein kinase C.

The Journal of Cell Biology ◽

10.1083/jcb.114.4.809 ◽

1991 ◽

Vol 114 (4) ◽

pp. 809-820 ◽

Cited By ~ 27

Author(s):

T B Vaidya ◽

C M Weyman ◽

D Teegarden ◽

C L Ashendel ◽

E J Taparowsky

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Transcriptional Activation ◽

Signal Transduction Pathway ◽

Phospholipid Metabolism ◽

Skeletal Myogenesis ◽

Wild Type ◽

Myogenic Regulatory Factor ◽

Kinase C ◽

Ras P21

Expression of the oncogenic form of H-ras p21 in the mouse myogenic cell line, 23A2, blocks myogenesis and inhibits expression of the myogenic regulatory factor gene, MyoD1. Previous studies from a number of laboratories have demonstrated that the activation of ras p21 is associated with changes in phospholipid metabolism that directly, or indirectly, lead to elevated levels of intracellular diacylglycerol and the subsequent activation of protein kinase C (PKC). To assess the importance of PKC activity to the ras-induced inhibition of skeletal myogenesis, we examined the levels of PKC activity associated with the terminal differentiation of wild-type myoblasts and with the differentiation-defective phenotype of 23A2 ras cells. We demonstrate that there is a 50% reduction in PKC activity during normal myogenesis and that PKC activity is required for myoblast fusion, but not for the transcriptional activation of muscle-specific genes. In contrast, we found that the differentiation-defective 23A2 ras cells possess two- to threefold more PKC activity than wild-type myofibers and that reducing the PKC activity in these cultures does not reverse their non-myogenic phenotype. On the other hand, if PKC activity is downregulated in 23A2 cells before the expression of activated ras p21, myogenesis is not inhibited. These results suggest that activated ras p21 relies on a PKC-dependent signal transduction pathway to initiate, but not to sustain, its negative effects on 23A2 skeletal myogenesis and underscore the potential importance of PKC activity to the proper control of skeletal muscle differentiation.

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Post-transcriptional regulation of H-ferritin gene expression in human monocytic THP-1 cells by protein kinase C

Biochemical Journal ◽

10.1042/bj3190185 ◽

1996 ◽

Vol 319 (1) ◽

pp. 185-189 ◽

Cited By ~ 9

Author(s):

Jong-Hwei S. PANG ◽

Chia-Jung WU ◽

Lee-Young CHAU

Keyword(s):

Gene Expression ◽

Protein Synthesis ◽

Protein Kinase C ◽

Protein Kinase ◽

Human Fibroblasts ◽

Leukaemic Cell ◽

Protein Synthesis Inhibitor ◽

Kinase C ◽

Ferritin Gene ◽

The Stability

The mRNA coding for H-ferritin was highly induced in human monocytic THP-1 cells following treatment with phorbol 12-myristate 13-acetate (PMA). The induction was detected at 3 h, reached maximal levels at 12 h, and was sustained for up to 48 h subsequent to PMA exposure. PMA-induced up-regulation of H-ferritin gene expression was also observed in other leukaemic cell lines, HL60 and U937, but not in non-leukaemic cell types, including human fibroblasts, endothelial cells and smooth muscle cells. The effect of PMA could be completely blocked by the protein kinase C inhibitor, H-7. Furthermore, treatment of THP-1 cells with bacterial phospholipase C also produced a marked increase in expression of H-ferritin mRNA, suggesting the activation of protein kinase C was responsible for the accumulation of mRNA. Nuclear run-off experiments demonstrated that PMA did not increase the transcriptional rate of the H-ferritin gene. In contrast, the half-life of the H-ferritin mRNA measured in the presence of actinomycin D was greatly prolonged in PMA-treated cells. The induction of H-ferritin mRNA by PMA required no protein synthesis. Conversely, treatment of THP-1 cells with protein synthesis inhibitor, cycloheximide, resulted in a 4–5-fold increase in H-ferritin mRNA. The increase in the stability of the H-ferritin mRNA was also observed in cells treated with cycloheximide. Taken together, these results suggest that the stability of H-ferritin mRNA in THP-1 is subjected to regulation via a protein kinase C-mediated phosphorylation on existing putative protein factor(s).

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