Protein kinase C pathway

Blumberg PM (1991) Complexities of the protein kinase C pathway Mol Carcinog 4 339-344... 

As a result of the action of IP3, [Ca2+], is increased, i.e., the calcium signal is generated. The other product of PIP2 hydrolysis, DG, has been shown to activate a protein kinase (protein kinase C) [8], The DG/protein kinase C pathway appears to function in the modulation of the calcium signal. Protein kinase can phospho-rylate and activate the 5-phosphomonoesterase thereby lowering the IP3 concentration and subsequently decreasing the intracellular free calcium concentration. 

Bradykinin, endothelin and prostacyclin are released in myocardial ischemia. Bradykinin acts through B2 and Bj receptor and is inactivated by ACE and NEP (cell surface zinc metalloprotease). Figure 13. Activation of B2 receptor can confer protection through activation of the nitric oxide/protein kinase C pathway or through the activation of PI3K/Akt prosurvival pathway (see figures 10,11). Furthermore, activation of B, receptor mediates protection to endothelium, limits noradrenaline outflow and reduces the occurrence of arrhythmias induced by ischemia and reperfusion.99... 

Antibodies recognizing both nuclear and cytosolic forms of FGF-2 have been employed in ultrastructural and cell fractionation analyses of the neuron-like adrenal chromaffin cells (Stachowiak et al., 1994 Bieger et al., 1995). Interestingly, in these studies, Nuclear (amino-terminally extended) and cytoplasmic forms were found in both nuclear and cytosolic fractions. A substantial fraction of FGF-2 was located on the outer surface of the cell membrane, consistent with the well-documented presence of FGF-2 in the extracellular matrix. Most of the cytoplasmic FGF-2 was found in endosome-like structures, while secretory granules, which had previously been reported to contain FGF-2 (Westermann et al., 1990), were devoid of label at the ultrastructural level. Accumulation of FGF in the nucleus or the cytoplasm could be triggered by activating either cAMP or protein kinase C pathways. However, the mechanism by... 

Cell-surface receptors use secondary messengers to generate a cell response. Cyclic AMP, cyclic GMP, and Ca + ions act as secondary messengers. Secondary messengers activate protein kinase A and protein kinase C pathways, both of which can phosphorylate and activate intracellular proteins, leading to mediation of cellular response (Figure 7.5). 

Recent reports suggest the existence in plant cells of all of the main components of this IP3/Ca+ and DAG/protein kinase C signal transduction system. A protein kinase C-like enzyme was partially purified from zucchini [17] and wheat cells [14]. It was also recently reported that IP3/Ca and DAG/protein kinase C pathways are involved in carrot cell response to an elicitor [9]. 

Enan E, Matsumura F (1993) Activation of phosphoinositide protein kinase C pathway in rat brain tissue by pyrethroids. Biochem Pharmacol 45 703... 

H.J. Im, etal, Basic fibroblast growth factor stimulates matrix metalloproteinase-13 via the molecular cross-talk between the mitogen-activated protein kinases and protein kinase c pathways in human adult articular chondrocytes, J. Biol Chem., 282 (15), 11110-11121, 2007b. http //dx.doi.org/10.1074/jbc.M609040200. 

Blumberg, P.M., G.R. Pettit, B.S. Warren, A. Szallasi, L.D. Schuman, N.A. Sharkey, H. Nakakuma, M.L. Dell Aquila, and D.J. de Vries The Protein Kinase C Pathway in Tumor Promotion. In Skin Carcinogenesis Mechanisms and Human Relevance, p. 201. Alan R. Liss, Inc. 1989. 

We have already seen how the two products of phosphatidylinositol bisphosphate hydrolysis can interact through their cellular effects. A good example is liver, where the inositol 1,4,5-triphosphate/Ca pathway controls the activity of phosphorylase kinase whereas the diacylglycerol/ protein kinase C pathway switches off glycogen synthetase. 

---