Diabetes is characterized by major changes in the microvascular system. Multiple pathways exist that explain the occurrence of vascular and cellular changes in diabetes. These are abnormalities in oxidation pathways, polyol pathways, glycation end products and protein kinase C (PKC) pathways. Drugs that inhibit PKC-beta are being developed and some of the drugs such as riboxstaurin that are bei...

The ability of insulin to stimulate protein synthesis and cellular growth is mediated through the insulin receptor (IR), which phosphorylates Tyr residues in the insulin receptor substrate-signaling proteins (IRS-1 and IRS-2), Gab-1, and Shc. These phosphorylated substrates directly bind and activate enzymes such as phosphatidylinositol 3'-kinase (PI3K) and the guanine nucleotide exchange facto...

The nonstructural protein 3 (NS3) of hepatitis C virus (HCV) inhibits the nuclear transport and the enzymatic activity of the catalytic subunit of protein kinase A. This inhibition is mediated by an arginine-rich domain localized between amino acids 1487-1500 of the HCV polyprotein. The data presented here indicate that the arginine-rich domain, when embedded in recombinant fragments of NS3, in...

Protein kinase C (PKC) (EC 2.7.11.13) (Enzyme Nomenclature 1992), represents a family of phospholipid-dependent serine/threonine phosphotransferases which are members of the protein kinase A (PKA), G and C superfamily. Most isoforms of PKC are activated in the presence of calcium (Ca) and diacylglycerol (DAG) (Nishizuka 1995). Once activated, these isozymes play central regulatory roles in a mu...

Stimulation of the B cell Ag receptor (BCR) induces activation of tyrosine kinases such as Lyn and Syk, phosphorylation and activation of multiple signaling components, and eventually, the expression of several genes including c-myc. Syk is required for activation of phospholipase C-gamma 2 and the subsequent phosphatidylinositol hydrolysis, leading to protein kinase C (PKC) activation and intr...

Using two types of anti-phosphopeptide antibodies which specifically recognize vimentin phosphorylated by protein kinase C (PKC) at two distinct PKC sites, we found that PKC acted as a mitotic vimentin kinase. Temporal change of vimentin phosphorylation by PKC differed form changes by cdc2 kinase. The mitosis-specific vimentin phosphorylation by PKC was dramatically enhanced by treatment with a...

Repeated intermittent treatment with amphetamine (AMPH) induces both neurite outgrowth and enhanced AMPH-stimulated dopamine (DA) release in PC12 cells. We investigated the role of protein kinases in the induction of these AMPH-mediated events by using inhibitors of protein kinase C (PKC), mitogen activated protein kinase (MAP kinase) or protein kinase A (PKA). PKC inhibitors chelerythrine (100...

Wang, L. D., M. Wang, A. Todisco, E. Grand, and J. Del Valle. The human histamine H2 receptor regulates c-jun and c-fos in a differential manner. Am J Physiol Cell Physiol 278: C1246–C1255, 2000.—Previously, we demonstrated that activation of the human H2 receptor (hH2R) leads to an increase in c-fos transcription and cell proliferation. The purpose of these studies was to examine whether hH2R ...