Guanine nucleotide dependent receptor

Figure 5. Guanine-nucleotide-dependent receptor interconversion from LRG" to LR. Penneabilized cells (10 /mL) (no GTPyS 1 ml Mg " ) were allowed to bind FLPEP for 1 min. Data analysis begins with the addition of antibody to fluorescein (after 60 s, but not indicated). At 90 s (indicated), GTPyS is added to induce interconversion to the rapidly dissociating state. The guanine nucleotide concentrations are shown (saturated at 10" If). The solid lines are the fit to the onestep model shown in the inset, and the k for the fit is shown at the end of each solid line. Data...

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. ...

Phillips, W. J., and Cerione, R. A. (1988). The intrinsic fluorescence of the a subunit of transducin. Measurement of receptor-dependent guanine nucleotide exchange./ Biol. Chem. 263, 15498-15505. 

Glucagon increases intracellular cAMP by binding to a surface receptor which is coupled to adenylate cyclase by a stimulatory guanine nucleotide binding protein (Gs). The sole target of cAMP in mammalian cells is the cAMP-dependent protein... 

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