Ion channel gating

Tieleman, D. P., Shrivastava, I. H., Ulmschneider, M. R., and Sansom, M. S. (2001) Pro-line-induced hinges in transmembrane helices possible roles in ion channel gating. Proteins 44, 63-72. 

Ion channels gated by ligands or membrane potential are central to signaling in neurons and other cells. 

Blatt, M.R. Thiel, G. (1993). Hormonal control of ion channel gating. Ann. Rev. Plant Physiol. Plant Mol. Biol. 44, 543-567. 

I. Goychuk and P. Hanggi, Ion channel gating A first-passage time analysis of the Kramers type. Proc. Natl. Acad. Sci. USA 99(6) 3552-3556 (2002). 

Fig. 5. (A) Mechanism for potassium ion channel gating as proposed by MacKinnon...

Stora T, Lakey JH, Vogel H. Ion-channel gating in transmembrane receptor proteins Functional activity in tethered lipid membranes. Angew. Chem. Int. Ed. 1999 38 389-392. 

As illustrated in Fig. 2, nonlinear time-series analyses are necessary to precisely represent the system dynamics at various spatial levels. The time scales can span from nanoseconds to seconds, from hours to days, years, and decades. For example, the ion channel gating events can be measured at the microsecond scale, the depolarization of the heart can be measured at the millisecond scale, and the stability of the cardiac cycle can be measured at the second scale [22], In addition, the longevity and aging of the organism can be measured at the gigasecond scale. 

Electrical conduction in normal myocardium is dependent upon the precise tem -ral orchestration of the gating kinetics of ion channels, which collectively result in the initiation and propagation of an action potential. During myocardial ischemia, the kinetics of ion channel gating are altered, resulting in changes in electrophysi-ological properties which predispose ischemic myocardium to lethal ventricular dysrhythmias, such as ventricular tachycardia and fibrillation. 

Inhibits L-type Ca " channels in cardiac and vascular smooth muscle cells by modulating ion channel gating mechanisms decreases systemic blood pressure and heart contractility... 

Inhibits L-type Ca" channels in cardiac and vascular smooth muscle cells more selective for the myocardium with minimal vasodilatory effects compared with dihydropyridines class IV antiarrhythmic agents Inhibits L-type Ca " " channels in cardiac and vascular smooth muscle cells by modulating ion channel gating mechanisms decreases systemic blood pressure and heart contractility Binds with high affinity to the alpha2-delta subunit of voltagegated Ca " " channels in CNS anticonvulsant drug Inhibits neuronal fast Nay channels, and thus blocks the action potential inhibits also cardiac Nay channels... 

Kienker, P. Matching Fractal Ion Channel Gating Models with Markov Models Preprint, 1989. 

This means that the molecular configuration of ion channel gating may be realized by relatively simple amino acid residues, and by peptides only. If so, the observed channeling phenomena both in BLM with the presence of HIM and in proteinoid vesicles may be understood. 

Bio membranes are fluid structures in which the phospholipid molecules and some of the embedded proteins diffnse rapidly in the plane of the membrane. They contain ion channels, gates, pumps and so forth and ntilise various mechanisms to allow the transport of ions or molecnles through them (in a perpendicnlar direction). 

Key words Pore water-electric fields-ion channels - gating... 

Millhauser, G. L, Salpeter, E. E. Oswald, R. E. (1988). Diffusion models of ion-channel gating and the origin of power-law distributions from singlechannel recording. Proceerttngs of the NatUmal Academy of ScietKes, USA, 85, 1503-7. 

In addition to the examples mentioned in Sect. 4, methyl-TROSY has also been used to explore co-translational folding of a ribosome-bound nascent chain [56] as well as the structural basis for ion channel gating [57]. It is worth mentioning that most membrane proteins fall into the size range of TROSY experiments, and the methods reviewed here are relevant to their study. 

HT3 Ion channel Gating of Na+ and K+. Activation leads to desensitising depolarization. 

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