Transduction oxides

In other membranes responsible for energy transduction, oxidation-reduction reactions are the basis for proton movement across the membrane. The classical example is found in mitochondria where electron flow through the respiratory system drives proton movement from the inner matrix to the intermembrane space. The resultant protonmotive force is used to drive ATP synthesis or to maintain mitochondrial membrane potential (negative inside). A similar association between electron transport in a membrane oxidation reduction chain and proton movement... 

Grb-2 facilitates the transduction of an extracellular stimulus to an intracellular signaling pathway, (b) The adaptor protein PSD-95 associates through one of its three PDZ domains with the N-methyl-D-aspartic acid (NMDA) receptor. Another PDZ domain associates with a PDZ domain from neuronal nitric oxide synthase (nNOS). Through its interaction with PSD-95, nNOS is localized to the NMDA receptor. Stimulation by glutamate induces an influx of calcium, which activates nNOS, resulting in the production of nitric oxide. 

Figure 1. Simplified schematic of receptor-mediated signal transduction in neutrophils. Binding of ligand to the receptor activates a guanine-nucleotide-binding protein (G protein), which then stimulates phospholipase C. Phosphatidylinositol 4,5-bis-phosphate is cleaved to produce diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3). DAG stimulates protein kinase C. IP3 causes the release of Ca from intracellular stores, which results in an increase in the cytosolic Ca concentration. This increase in Ca may stimulate protein kinase C, calmodulin-dependent protein kinases, and phospholipase A2. Protein phosphorylation events are thought to be important in stimulating degranulation and oxidant production. In addition, ionic fluxes occur across the plasma membrane. It is possible that phospholipase A2 and ionic channels may be governed by G protein interactions. ...

Dorman G (2000) Photoaffinity Labeling in Biological Signal Transduction. 211 169-225 Drabowicz J, Mikolajczyk M (2000) Selenium at Higher Oxidation States. 208 143-176 Eder B, see Wrodnigg TM (2001) The Amadori and Heyns Rearrangements Landmarks in the History of Carbohydrate Chemistry or Unrecognized Synthetic Opportunities 215 115-175... 

While the fluid mosaic model of membrane stmcture has stood up well to detailed scrutiny, additional features of membrane structure and function are constantly emerging. Two structures of particular current interest, located in surface membranes, are tipid rafts and caveolae. The former are dynamic areas of the exo-plasmic leaflet of the lipid bilayer enriched in cholesterol and sphingolipids they are involved in signal transduction and possibly other processes. Caveolae may derive from lipid rafts. Many if not all of them contain the protein caveolin-1, which may be involved in their formation from rafts. Caveolae are observable by electron microscopy as flask-shaped indentations of the cell membrane. Proteins detected in caveolae include various components of the signal-transduction system (eg, the insutin receptor and some G proteins), the folate receptor, and endothetial nitric oxide synthase (eNOS). Caveolae and lipid rafts are active areas of research, and ideas concerning them and their possible roles in various diseases are rapidly evolving. 

Transduction in an Oscillating Field Electric Breakdown in Anodic Oxide Films 23... 

Jung, H. W. Chung, Y. S. Kim, Y. S. Park, Y.-K. Celastrol inhibits production of nitric oxide and proinflammatory cytokines through MAPK signal transduction and NF-kB in LPS-stimulated BV-2 microglial cells. Exp. Mol. Med. 2007, 39, 715-721. 

FIGURE 8.11 Multiple signal-transduction pathways initiated by calmodulin. Calmodulin bound to Ca2+ interacts and activates many enzymes, opening up a wide range of possible cellular responses. Abbreviations MAP-2, microtubule-associated protein 2 NO, nitric oxide Tau, tubulin assembly unit. 

Developmental exposure to Pb or Mm affect signal transduction process, possibly related to the modulation of nitric oxide as well as alterations in receptor-mediated phosphoinositide hydrolysis and protein kinase C (rats)... 

Owuor, ED. and Kong, AN. 2002. Antioxidants and oxidants regulated signal transduction pathways. Biochem Pharmacol 64 765-770. 

Vranova, E., Inze, D. and Van Breusegem, F. (2002). Signal transduction during oxidative stress. Journal of Experimental Botany 53 1227-1236. 

L.J. Ignarro, Nitric-Oxide - A novel signal transduction mechanism for transcellular communication. 

Our work on thiolato oxidation is of broader relevance, as there is much current interest in the function of protein cysteinyl sulfenates in signal transduction, oxygen metabolism, oxidative stress, and their role in the activity of nitrile hydratase (98-100). 

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