scholarly journals Phosphatidylcholine-dependent protein kinase C activation. Effects of cis-fatty acid and diacylglycerol on synergism, autophosphorylation and Ca2+-dependency

1992 ◽  
Vol 284 (1) ◽  
pp. 221-226 ◽  
Author(s):  
S G Chen ◽  
D Kulju ◽  
S Halt ◽  
K Murakami
Keyword(s):  
Protein Kinase C ◽  
Fatty Acid ◽  
Protein Kinase ◽  
Acid Activation ◽  
Type Iii ◽  
Kinase C ◽  
Synergistic Activation ◽  
Protein Kinase C Activity ◽  
Fatty Acid Activation ◽  
Protein Kinase C Activation

A long-chain neutral phospholipid, dioleoylphosphatidylcholine, was found to support protein kinase C activation by cis-fatty acid and diacylglycerol (DAG). This effect of phosphatidylcholine (PC) is totally dependent on the presence of cis-fatty acid; PC greatly stimulates the cis-fatty acid-induced protein kinase C activity, but it does not activate protein kinase C at all, even in the presence of DAG, if cis-fatty acid is absent. DAG, however, plays a modulatory role in the presence of Ca2+; it further enhances the PC-potentiated cis-fatty acid activation of protein kinase C. Although the activities of all three protein kinase C subtypes tested (types I, II and III) are supported by this PC mechanism, type III is most sensitive to the DAG effect, and it is activated synergistically by cis-fatty acid and DAG. The potency of PC to support the synergistic activation of this subtype is equivalent to that of phosphatidylserine (PS). There are several differences, however, between PC- and PS-supported synergism observed in type III protein kinase C: (1) Ca(2+)-sensitivity is different; PC requires higher concentrations of Ca2+ (10-20 microM-Ca2+) than those required for PS (micromolar Ca2+); (2) PC/cis-fatty acid/DAG-induced autophosphorylation of protein kinase C subtypes (types I, II and III) is very weak, whereas PS/cis-fatty acid/DAG strongly stimulate autophosphorylation of these subtypes under the conditions at which both PC and PS systems fully activate the protein kinase C in terms of histone phosphorylation. These observations suggest that a neutral phospholipid such as PC may also participate in the activation and differential regulation of protein kinase C.

scholarly journals Synergistic activation of type III protein kinase C by cis-fatty acid and diacylglycerol

1992 ◽  
Vol 282 (1) ◽  
pp. 33-39 ◽  
Author(s):  
S G Chen ◽  
K Murakami
Keyword(s):  
Protein Kinase C ◽  
Fatty Acid ◽  
Protein Kinase ◽  
Second Messengers ◽  
Type I ◽  
Physiological Concentration ◽  
Type Iii ◽  
Kinase C ◽  
Synergistic Activation ◽  
Protein Kinase C Activation

Micromolar concentrations of cis-fatty acid synergistically activate type III protein kinase C with diacylglycerol. This synergistic effect occurs at low concentrations of cis-fatty acid and diacylglycerol, and it is capable of inducing almost full activation of this protein kinase C subtype at a physiologically relevant Ca2+ concentration (2 microM). The synergistic activation mode can be observed even in the absence of Ca2+, but micromolar Ca2+ significantly enhances the type III protein kinase C activation. cis-Fatty acid also augments the diacylglycerol-induced activation of other subtypes (type I and II), although the effect is smaller than that observed in type III. Neither the diacylglycerol- nor the cis-fatty acid-dependent mode of activation can fully activate any of these subtypes at a physiological concentration of Ca2+ (2 microM). Our results suggest that the generation of three second messengers, i.e. the increase in intracellular Ca2+ concentration and the generation of both cis-fatty acid and diacylglycerol in the cell, may be necessary signals for protein kinase C activation, particularly for type III protein kinase C.

scholarly journals Effect of cis-unsaturated fatty acids on aortic protein kinase C activity

1989 ◽  
Vol 258 (1) ◽  
pp. 171-175 ◽  
Author(s):  
K R Dell ◽  
D L Severson
Keyword(s):  
Fatty Acids ◽  
Protein Kinase C ◽  
Oleic Acid ◽  
Fatty Acid ◽  
Protein Kinase ◽  
Unsaturated Fatty Acids ◽  
Acid Activation ◽  
Kinase C ◽  
Protein Kinase C Activity ◽  
Fatty Acid Activation

Long-chain cis-unsaturated fatty acids could substitute for phosphatidylserine and activate bovine aortic protein kinase C in assays with histone as substrate. The optimal concentration was 24-40 microM for oleic, linoleic and arachidonic acids. With arachidonic acid, the Ka for Ca2+ was 130 microM and kinase activity was maximal at 0.5 mM-Ca2+. Diolein only slightly activated the oleic acid-stimulated enzyme at low physiological Ca2+ concentrations (0.1 and 10 microM). Oleic acid also stimulated kinase C activity, determined with a Triton X-100 mixed-micellar assay. Under these conditions, the fatty acid activation was absolutely dependent on the presence of diolein, but a Ca2+ concentration of 0.5 mM was still required for maximum kinase C activity. The effect of fatty acids on protein kinase C activity was also investigated with the platelet protein P47 as a substrate, since the properties of kinase C can be influenced by the choice of substrate. In contrast with the results with histone, fatty acids did not stimulate the phosphorylation of P47 by the aortic protein kinase C. Activation of protein kinase C by fatty acids may allow the selective phosphorylation of substrates, but the physiological significance of fatty acid activation is questionable because of the requirement for high concentrations of Ca2+.

Free fatty acids and protein kinase C activation induce GPR120 (free fatty acid receptor 4) phosphorylation

2014 ◽  
Vol 723 ◽  
pp. 368-374 ◽  
Author(s):  
Omar B. Sánchez-Reyes ◽  
M. Teresa Romero-Ávila ◽  
Jean A. Castillo-Badillo ◽  
Yoshinori Takei ◽  
Akira Hirasawa ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Protein Kinase C ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Protein Kinase ◽  
Free Fatty Acids ◽  
Acid Receptor ◽  
Kinase C ◽  
Free Fatty Acid Receptor ◽  
Protein Kinase C Activation
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