Calcium G protein

Somlyo AP, Somlyo AV 2000 Signal transduction by G-proteins, Rho-kinase and protein phosphatase to smooth muscle and non-muscle myosin II. J Physiol 522 177—185 Somlyo AP, Devine CE, Somlyo AV, N orth SR 1971 Sarcoplasmicreticulumand the temperature-dependent contraction of smooth muscle in calcium-free solutions. J Cell Biol 51 722—741 Somlyo AP, Walker JW, Goldman YE et al 1988 Inositol trisphosphate, calcium and muscle contraction. Philos Trans R Soc Lond B Biol Sci 320 399 114 Somlyo AP, Wu X, Walker LA, Somlyo AV 1999 Pharmacomechanical coupling the role of calcium, G-proteins, kinases and phosphatases. Rev Physiol Biochem Pharmacol 134 201-234... 

Pharmacomechanical coupling the role of calcium, G-proteins, kinases and phosphatases... 

The Role of Calcium, G-Proteins, Kinases and Phosphatases By A. P. Somlyo, X. Wu, L. Walker, and A. V. Somlyo, Charlottesville, Virginia, USA... 

The second important compartment for strontium is blood. Analogous to bone, the concentration is influenced by the dietary intake of strontium, calcium, and phosphate [66], Moreover, the values measured may vary strongly with the analytical technique used (Table 1). Within the blood compartment, strontium is bound by serum proteins with a maximal binding capacity of 0.128 mmol strontium/g protein (the maximal binding capacity of calcium amounts to 0.190 mmol calcium/g protein) [47,67],... 

Excitation of smooth muscle via alpha-1 receptors (eg, in the utems, vascular smooth muscle) is accompanied by an increase in intraceUular-free calcium, possibly by stimulation of phosphoUpase C which accelerates the breakdown of polyphosphoinositides to form the second messengers inositol triphosphate (IP3) and diacylglycerol (DAG). IP3 releases intracellular calcium, and DAG, by activation of protein kinase C, may also contribute to signal transduction. In addition, it is also thought that alpha-1 adrenergic receptors may be coupled to another second messenger, a pertussis toxin-sensitive G-protein that mediates the translocation of extracellular calcium. 

Ca2+ sensing receptor, a member of G-protein coupled receptors, is composed of seven transmembrane spanning domains. The extracellular domain contains clusters of negatively charged amino acids sensing even small fluctuations of extracellular calcium. Mutations in this receptor cause inheritable hypo- and hypercalcemic syndromes. 

Krebs J, Heizmann CW (2007) Calcium-binding proteins and the EF-hand principle. In Krebs J, Michalak M (eds) Calcium a matter of life and death, New Comprehensive Biochemistry, vol 41 (Series Bernardi G). Elsevier, pp 51-93... 

Functionally, the Dl-like receptors (Dl, D5) are coupled to the G protein Gas and thus can stimulate adenylyl cyclase. The D2-like receptors (D2, D3, and D4) couple to pertussis toxin sensitive G proteins (Gai/0), and consequently inhibit adenylyl cyclase activity. While the Dl-like receptors almost exclusively signal through Gas-mediated activation of adenylyl cyclase, the D2-like receptors have been reported to modulate the activity of a plethora of signaling molecules and pathways. Many of these actions are mediated through the G(3y subunit. Some of these molecules and pathways include the calcium channels, potassium channels, sodium-hydrogen exchanger, arachidonic acid release, and mitogen-activated protein kinase pathways. 

The ETa receptor activates G proteins of the Gq/n and G12/i3 family. The ETB receptor stimulates G proteins of the G and Gq/11 family. In endothelial cells, activation of the ETB receptor stimulates the release of NO and prostacyclin (PGI2) via pertussis toxin-sensitive G proteins. In smooth muscle cells, the activation of ETA receptors leads to an increase of intracellular calcium via pertussis toxin-insensitive G proteins of the Gq/11 family and to an activation of Rho proteins most likely via G proteins of the Gi2/i3 family. Increase of intracellular calcium results in a calmodulin-dependent activation of the myosin light chain kinase (MLCK, Fig. 2). MLCK phosphorylates the 20 kDa myosin light chain (MLC-20), which then stimulates actin-myosin interaction of vascular smooth muscle cells resulting in vasoconstriction. Since activated Rho... 

S100G S100 calcium binding protein G Calbindin 3 (CALB3), CaBP9K, CABP1 Xp22 NM 004057... 

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