Nucleotide-gated ion channels

Kaupp UB, Seifert R (2002) Cyclic nucleotide-gated ion channels. Physiol Rev 82 769-824... 

Trudeau, M. C. and Zagotta, W. N. Calcium/calmodulin modulation of olfactory and rod cyclic nucleotide-gated ion channels. /. Biol. Chem. 278 18705-18708, 2003. 

POMC peptides derived from rat pituitary extracts prolactin-releasing peptides in the bovine hypothalamic extract pseudechetoxin, a peptide blocker of cyclic nucleotide-gated ion channels pseudo-peptide analogues of thiol proteinase inhibitors relaxin-like molecule from the male atlantic stingray, Dasyatis sabina... 

However, at this point a role for other second messengers in insect olfaction cannot be excluded. In fact, the observation that distinct cyclic nucleotide-gated ion channels are expressed in insect antennae (Baumann el al., 1994 Krieger el al., 1999a) may be the first evidence for functional implications of a cyclic nucleotide pathway. 

Ion channels Cng eag Cyclic-nucleotide-gated ion channel protein ether a go-go... 

Adenyl cyclase can be activated or inhibited by G-proteins, which are coupled to membrane receptors and thus can respond to hormonal or other stimuli. Following activation of adenyl cyclase, the resulting cAMP acts as a second messenger by interacting with and regulating other proteins, such as protein kinase A and cyclic nucleotide-gated ion channels. 

CNG channels (cyclic nucleotide-gated ion channels) are activated by the binding of cyclic GMP. They mediate sensory signal transduction in photoreceptors and olfactory cells. Six mammahan CNG channel genes are known and some human visual disorders are caused by mutations in retinal rod or cone CNG genes. ... 

Pifferi, S., Boccaccio, A., Menini, A. Cyclic nucleotide-gated ion channels in sensory transduction. FEBS Lett. 2006, 580, 2853-2859. 

Kruse LS, Sandholdt NTH, Gammeltoft S et al (2006) Phosphodiesterase 3 and 5 and cyclic nucleotide-gated ion channel expression in rat trigeminovascular system. Neurosci Lett 404 202-207... 

Pseudochetoxin inhibitors of cyclic nucleotide-gated ion channels [512]... 

Figure 2.5. The synapse. GPCR = guanine nucleotide-binding protein-coupled receptor, LGICR = ligand-gated ion channel receptor, SB = synaptic bouton, T = neurotransmitter, YOC = voltage-operated ion channel protein, YOCC = voltage-operated calcium channel protein, Ast = astrocyte, AA = axoaxonal synapse, ASD = axosomatic or axodendritic synapse. GPCR 1 = receptor protein, 2 = G-protein, 3 = enzyme, 4 = ion channel protein.

Cyclic nucleotide-modulated ion channels (Table 6-2) are not K+-selective. Nevertheless, their inward current of Na+ and Ca2+ ions is conducted through a channel that is similar in overall architecture to Shaker K+ channels. This protein family includes the CNG channels, which respond only to cyclic nucleotides, and the HCN channels, which are activated synergistically by hyperpolarization and cyclic nucleotide binding [38,40]. The CNG channels are involved in signaling of visual and olfactory information and serve as cyclic nucleotide-gated Ca2+ channels. In contrast, the HCN channels are required for normal rhythmic electrical discharges by the sinoatrial node in the heart and the pacemaker cells of the thalamus. 

Abstract Adenine-based purines, such as adenosine and ATP, are ubiquitous molecules that, in addition to their roles in metabolism, act as modulators of neurotransmitter release through activation of presynaptic PI purinoceptors or adenosine receptors (activated by adenosine) and P2 receptors (activated by nucleotides). Of the latter, the P2Y receptors are G protein-coupled, whereas the P2X receptors are ligand-gated ion channels and not covered in this review. 

Hatt, H. and Ache, B. W., Cyclic nucleotide- and inositol phosphate-gated ion channels in lobster olfactory receptor neurons, Proc. Natl. Acad. Sci. USA, 91, 6264, 1994. 

Pivotal role of nucleotide P2X2 receptor subunit of the ATP-gated ion channel mediating ventilatory responses to hypoxia. J Neurosci 23 11315-11321. 

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