Protein kinase C PKC

The spatial and steric requirements for high affinity binding to protein kinase C (PKC), a macromolecule that has not yet been crystallized, were determined. Protein kinase C plays a critical role in cellular signal transduction and is in part responsible for cell differentiation. PKC was identified as the macromolecular target for the potent tumor-promoting phorbol esters (25). The natural agonists for PKC are diacylglycerols (DAG) (26). The arrows denote possible sites of interaction. 

The tjipanazoles (18, 19a-d, 20a-b) a group of A-glycosides of indolo-[2,3-a]carbazole, have been isolated from the moderately antifungal extract of the blue-green alga Tolypothrix tjipanasensis. These alkaloids do not exhibit antitumor or protein kinase C (PKC) inhibitory activity, which is in contrast with the... 

Apelin receptors activate several signalling pathways including coupling through inhibitory G-proteins (G ) and Ras-independent activation of extracellular-regulated kinases (ERKs) via protein kinase C (PKC). The apelin receptor is one of number of G-protein-coupled receptors that can act as an alternative coreceptor for entry into cells of HIV and simian immunodeficiency vims (SIV) strains in human U87 cells expressing CD4 in vitro. Apelin peptides blocks entry of HIV but display different potencies, with apelin-36 being more effective than shorter sequences [3]. 

Heterologous desensitization is a form of desensitization which does not require agonist binding of the receptor. Second messenger dependent kinases such as protein kinase A (PKA) and protein kinase C (PKC) are involved in this form of receptor desensitization. Heterologous desensitization simply depends on the overall kinase activity which is regulated by many different stimuli. 

Fat Increased glucose transport GLUT4-translocation PI 3-kinase/Akt mediated translocation of GLUT4 into the plasma membrane. Potential involvement of atypical forms of protein kinase C (PKC and A)... 

Protein kinase C (PKC) is an enzyme family whose members are activated by agonists that cause receptor-mediated generation of lipid second messengers. The activated enzymes transduce information from such agonists by phosphorylating relevant downstream substrates. 

Koivunen J, Aaltonen V, Peltonen J (2006) Protein kinase C (PKC) family in cancer progression. Cancer Letts 235 1-10... 

TRPVl, also known as the capsaicin- or vanilloid-receptor, is a nonselective cation channel expressed e.g., in neurons of the dorsal root and trigeminal ganglions, which integrates multiple pain-producing stimuli including heat, protons, capsaicin, and resiniferatoxin. In addition, TRPVl currents can be activated by ananda-mide, protein kinase C (PKC), and by hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2). 

In chronic myelogenous leukemia (CML) as well as in a subset of acute lymphoblastic leukemia (ALL) Bcr-Abl, a fusion protein of c-Abl and the breakpoint cluster region (bcr), is expressed in the cytosol of leukemic cells. This fusion protein forms homo-oligomeric complexes that display elevated kinase activity and is the causative molecular abnormality in CML and certain ALL. The transforming effect of Bcr-Abl is mediated by numerous downstream signaling pathways, including protein kinase C (PKC), Ras-Raf-ERK MAPK, JAK-STAT (see below), and PI3-kinase pathways. 

Genes involved in the uptake and degradation of tocopherols - Genes implicated with lipid uptake and. Mi / °f J - Protein kinase C (PKC) - Cyclooxygenase - 5-Lipoxygenase - Cytokine release (IL-1P)... 

DAG is a potent activator of protein kinase C (PKC). It has been long known that ACh causes an increase in the number of effective L-channels in many smooth muscle cells. This effect is mimicked by phorbol esters (known to activate PKC) and DAG itself Therefore, it has been suggested that one of the actions of ACh involves the activation of L-channels via the evoked increase of DAG. 

Recent evidence indicates that the 5-HT transporter is subject to post-translational regulatory changes in much the same way as neurotransmitter receptors (Blakeley et al. 1998). Protein kinase A and protein kinase C (PKC), at least, are known to be involved in this process. Phosphorylation of the transporter by PKC reduces the Fmax for 5-HT uptake and leads to sequestration of the transporter into the cell, suggesting that this enzyme has a key role in its intracellular trafficking. Since this phosphorylation is reduced when substrates that are themselves transported across the membrane bind to the transporter (e.g. 5-HT and fi -amphetamine), it seems that the transport of 5-HT is itself linked with the phosphorylation process. Possibly, this process serves as a homeostatic mechanism which ensures that the supply of functional transporters matches the demand for transmitter uptake. By contrast, ligands that are not transported (e.g. cocaine and the selective serotonin reuptake inhibitors (SSRIs)) prevent the inhibition of phosphorylation by transported ligands. Thus, such inhibitors would reduce 5-HT uptake both by their direct inhibition of the transporter and by disinhibition of its phosphorylation (Ramamoorthy and Blakely 1999). 

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