G-proteins


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G-proteins

cell membrane receptor proteins that interact with inflammatory mediators to induce intracellular changes; myasthenia gravis and familial hypercholesterolaemia are both caused by G-protein defects
References in periodicals archive ?
Activated RTKs activate small G-proteins (from the Ras, Rho, and Raf families), which in turn activate guanine nucleotide exchange factors such as SOS1.
Finally, ethanol treatment had differential effects on various G-proteins in cells expressing only D2S or D2L, eliciting a marked increase in Gs expression and a decrease in Gi3 expression in D2S cells but a moderate increase in Gs and marked increase in Gi3 expression in D2L (Sengupta and Sarkar 2012).
This pointed in the direction that other GPCRs turning on G-proteins would also have this form, which has turned out to be the case with the more than 800 members of this family that are now known in humans.
The cholera toxin prevents the inactivation of G-proteins in intestinal cells, causing uncontrolled secretion of water and salts into the gastro-intestinal tract and severe watery diarrhoea.
The signaling cascades involved in mast cell activation are interaction of an antigen with its specific IgE antibody on mast cell surface, tyrosines phosphophorylation of phospholipase C-g1 (PLC-g1), hydrolysis of phosphatidyl inositol 4,5-biphosphate, formation of inositol triphosphate (IP3) and diacylglycerol (DAG), activation of protein kinase C (PKC), intracellular Ca2+ mobilization by IP3, increase of Ca2+ influx to cytoplasma, activation of mitogen-activated protein kinase (MAP kinases) and G-protein.
Here's an example: I started out doing G-protein coupled receptor drug discovery (which was the source of all my mistaken confidence about nuclear receptors).
The bottom line is that in order to effectively suppress aldosterone production, you need to inhibit beta-arrestin-1 in addition to inhibiting G-proteins," said Lymperopoulos.
The G-proteins are so named because they can bind the nucleotides GTP and GDP When a neurotransmitter binds to the receptor, the exchange of GTP for GDP at the intracellular side of the protein is accelerated, and this causes the G-protein to separate into two parts (the [alpha]-and [beta]/[gamma]-subunits), which dissociate from the receptor protein.
Known for its enabling, innovative solutions to help understand the biology of kinases, chromatin, g-proteins and cytokines, Upstate's advanced cell biology tools - drug screening services, enzymes, state specific antibodies, siRNA kits, multiplex assays are used by thousands of customers worldwide, every day to accelerate improving human health.
As all components of the AC activation pathway (GPCR-s, G-proteins, and AC) are membrane-bound proteins, the signal transduction has to function also in cell membrane preparations.
Small GTP-binding proteins (G-proteins) of the Rho family have been shown to regulate cytoskeleton reorganization, whereas G-proteins of the Rab family have been shown to regulate intracellular trafficking and vesicle transport (1).
The examples of conformation switching for enzyme proteins and G-proteins clearly demonstrate the point.