Calcium trigger

Anderson, J. M., Charbonneau, H., and Cormier, M. J. (1974). Mechanism of calcium induction of Renilla bioluminescence. Involvement of a calcium-triggered luciferin binding protein. Biochemistry 13 1195-1200. 

Deng, L., et al. (2004b). Crystal structure of a Ca2+-discharged photoprotein Implications for mechanisms of the calcium trigger and bioluminescence. J. Biol. Chem. 279 33647-33652. 

Hastings, J. W., and Morin, J. C. (1969). Calcium-triggered light emission in Renilla. A unitary biochemical scheme for coelenterate bioluminescence. Biochem. Biophys. Res. Commun. 37 493-498. 

Kumar, S., et al. (1990). Amino acid sequence of the calcium-triggered luciferin binding protein of Renilla reniformis. FEBS Lett. 268 287-290. 

Shimomura, O., and Johnson, F. H. (1976). Calcium-triggered luminescence of the photoprotein aequorin. Symp. Soc. Exp. Biol. 30 41-54. 

Augustine GJ (2001) How does calcium trigger neurotransmitter release Curr Opin Neurobiol 11 320-326... 

In this review, we consider the evidence that disturbances in calcium triggered by Ap may contribute to the synaptic loss in human AD. Furthermore, we discuss the likelihood that calcium dyshomeostasis in AD, and AD mouse models, may contribute to memory impairments. We have not discussed the role of the presenilins in calcium homeostasis as they have recently been reviewed (LaFerla, 2002 Smith... 

Figure 10-4. The structure of the calciumbinding protein troponin from chicken skeletal muscle. Although this is an exceptionally complicated ligand to a coordination chemist, the binding of calcium ions is to the hard donor sites that might be predicted. Binding of the calcium triggers a conformational change.

Jaiswal, J. K., Fix, M., Takano, T., Nedergaard, M., and Simon, S. M. (2007). Resolving vesicle fusion from lysis to monitor calcium-triggered lysosomal exocytosis in astrocytes. Proc. Natl. Acad. Sci. USA 104, 14151-14156. 

Fig. 15. A schematic representation of the binding site region of calcium trigger proteins (after Kretsinger). Using Ln(III) ions Sykes and coworkers181 demonstrated that the solution and crystal structures were very similar...

The taste receptor mechanism has been more fully described by Kurihara (1987). The process from chemical stimulation to transmitter release is schematically presented in Figure 7-4. The receptor membranes contain voltage-dependent calcium channels. Taste compounds contact the taste cells and depolarize the receptor membrane this depolarization spreads to the synaptic area, activating the voltage-dependent calcium channels. Influx of calcium triggers the release of the transmitter norepinephrine. 

Appel SH, Smith RG, Alexianu M, Siklos L, Engelhard J, Colom LV, Stefani E (1995). Increased intracellular calcium triggered by immune mechanisms in amyotrophic lateral sclerosis. Clin Neu-rosci 3 368-374. 

It should be remarked, however, that calcium plays a crucial role in the actin-myosin association/dissociation process. Calcium has a binding site on troponin, located on the surface of the actin thread, and binding of calcium triggers the contraction cycle. (Without calcium there is no association whatsoever.)... 

Parsons TD, Lenzi D, Aimers W, Roberts WM (1994) Calcium-triggered exocytosis and endocytosis in an isolated presynaptic cell capacitance measurements in saccular hair cells. Neuron 75 875-883. 

Fabiato, A. F. Fabiato. 1975. Contractions induced by a calcium-triggered release of calcium from the sarcoplasmic reticulum of single skinned cardiac cells./. Physiol. (Land.) 249 469-95. 

Due to the report by Manalis and Cooper in 1973 that lead inhibits calcium-triggered release of neurotransmitters (452), much attention has focused on the possibility that lead interacts with calcium proteins and/or affects calcium homeostasis (40, 173, 338-340, 351, 355, 443, 453 64). Indeed, patch clamp studies reveal that lead blocks voltage-dependent calcium channels (459, 464, 465), but the effects are highly dependent on the channel and cell type (460). In addition, lead has been shown to stimulate efflux from nerve cells via Ca -ATPase in a calmodulin-dependent fashion, resulting in a net decrease in... 

Rauh NR, Schmidt A, Bormann J, Nigg EA, Mayer TU. 2005. Calcium triggers exit from meiosis II by targeting the APC/C inhibitor XErpl for degradation. Nature 437(7061) 1048-1052. 

Figure 3 The cascade for vasodilation In mammals. Acetylcholine or bradykinin activates endothelial membrane receptors and activates the eNOS enzyme by enhancing the Intracellular calcium levels. The NO diffuses into the adjacent smooth muscle cells, where it stimulates the guanylate cyclase enzyme to produce cGMP. The latter activates protein kinase G, which stimulates outflux of K+ and Ca + from the cell. The drop in intracellular calcium triggers the relaxation of the muscle tissue. Alternatively, the guanylate cyclase In the smooth muscle cells may be activated by pharmaceutical NO donors in the bloodstream.

The increased intracellular concentration of free calcium triggers a series of hyperactive enzyme reactions with deleterious effects [65]. There are several examples ... 

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