Divalent Cation Selectivity in a Cyclic Nucleotide-Gated Ion Channel

Biochemistry ◽  
1995 ◽  
Vol 34 (41) ◽  
pp. 13328-13333 ◽  
Author(s):  
Chul-Seung Park ◽  
Roderick MacKinnon
Keyword(s):  
Ion Channel ◽  
Divalent Cation ◽  
Cyclic Nucleotide ◽  
Cation Selectivity

scholarly journals Divalent Cation Selectivity Is a Function of Gating in Native and Recombinant Cyclic Nucleotide–gated Ion Channels from Retinal Photoreceptors

1999 ◽  
Vol 113 (6) ◽  
pp. 799-818 ◽  
Author(s):  
David H. Hackos ◽  
Juan I. Korenbrot
Keyword(s):  
Divalent Cation ◽  
Cyclic Nucleotide ◽  
Divalent Cations ◽  
Ion Selectivity ◽  
Ion Concentration ◽  
Cone Photoreceptors ◽  
Cation Selectivity ◽  
Channel Opening ◽  
Α And Β Subunits ◽  
Α Subunits

The selectivity of Ca2+ over Na+ is ∼3.3-fold larger in cGMP-gated channels of cone photoreceptors than in those of rods when measured under saturating cGMP concentrations, where the probability of channel opening is 85–90%. Under physiological conditions, however, the probability of opening of the cGMP-gated channels ranges from its largest value in darkness of 1–5% to essentially zero under continuous, bright illumination. We investigated the ion selectivity of cGMP-gated channels as a function of cyclic nucleotide concentration in membrane patches detached from the outer segments of rod and cone photoreceptors and have found that ion selectivity is linked to gating. We determined ion selectivity relative to Na+ (PX/PNa) from the value of reversal potentials measured under ion concentration gradients. The selectivity for Ca2+ over Na+ increases continuously as the probability of channel opening rises. The dependence of PCa/PNa on cGMP concentration, in both rods and cones, is well described by the same Hill function that describes the cGMP dependence of current amplitude. At the cytoplasmic cGMP concentrations expected in dark-adapted intact photoreceptors, PCa/PNa in cone channels is ∼7.4-fold greater than that in rods. The linkage between selectivity and gating is specific for divalent cations. The selectivity of Ca2+ and Sr2+ changes with cGMP concentration, but the selectivity of inorganic monovalent cations, Cs+ and NH4+, and organic cations, methylammonium+ and dimethylammonium+, is invariant with cGMP. Cyclic nucleotide–gated channels in rod photoreceptors are heteromeric assemblies of α and β subunits. The maximal PCa/PNa of channels formed from α subunits of bovine rod channels is less than that of heteromeric channels formed from α and β subunits. In addition, Ca2+ is a more effective blocker of channels formed by α subunits than of channels formed by α and β subunits. The cGMP-dependent shift in divalent cation selectivity is a property of αβ channels and not of channels formed from α subunits alone.

Perfect divalent cation selectivity with capacitive deionization

2021 ◽  
pp. 117959
Author(s):  
Rana Uwayid ◽  
Eric N. Guyes ◽  
Amit Shocron ◽  
Jack Gilron ◽  
Menachem Elimelech ◽  
...  
Keyword(s):  
Divalent Cation ◽  
Capacitive Deionization ◽  
Cation Selectivity

Cyclic Nucleotide Gated Ion Channel 6 is involved in extracellular ATP signaling and plant immunity

2021 ◽  
Author(s):  
Ha N. Duong ◽  
Sung‐Hwan Cho ◽  
Limin Wang ◽  
An Q. Pham ◽  
Julia M. Davies ◽  
...  
Keyword(s):  
Ion Channel ◽  
Cyclic Nucleotide ◽  
Plant Immunity ◽  
Extracellular Atp ◽  
Atp Signaling

Binding orientation and specificity of calmodulin to rat olfactory cyclic nucleotide-gated ion channel

2013 ◽  
Vol 31 (4) ◽  
pp. 414-425 ◽  
Author(s):  
Deli Irene ◽  
Jian-Wen Huang ◽  
Tse-Yu Chung ◽  
Feng-Yin Li ◽  
Jason T.-C. Tzen ◽  
...  
Keyword(s):  
Ion Channel ◽  
Cyclic Nucleotide ◽  
Binding Orientation

Phosphodiesterase 3 and 5 and cyclic nucleotide-gated ion channel expression in rat trigeminovascular system

2006 ◽  
Vol 404 (1-2) ◽  
pp. 202-207 ◽  
Author(s):  
Lars S. Kruse ◽  
Nicolai T.H. Sandholdt ◽  
Steen Gammeltoft ◽  
Jes Olesen ◽  
Christina Kruuse
Keyword(s):  
Ion Channel ◽  
Cyclic Nucleotide ◽  
Trigeminovascular System ◽  
Phosphodiesterase 3 ◽  
Channel Expression

scholarly journals The Arabidopsis dnd1 "defense, no death" gene encodes a mutated cyclic nucleotide-gated ion channel

2000 ◽  
Vol 97 (16) ◽  
pp. 9323-9328 ◽  
Author(s):  
S. J. Clough ◽  
K. A. Fengler ◽  
I-c. Yu ◽  
B. Lippok ◽  
R. K. Smith ◽  
...  
Keyword(s):  
Ion Channel ◽  
Cyclic Nucleotide

Expression of subunits for the cAMP-sensitive ‘olfactory’ cyclic nucleotide-gated ion channel in the cochlea: implications for signal transduction

2002 ◽  
Vol 98 (1-2) ◽  
pp. 1-14 ◽  
Author(s):  
Marian J Drescher ◽  
Roberto L Barretto ◽  
Deepti Chaturvedi ◽  
Kirk W Beisel ◽  
James S Hatfield ◽  
...  
Keyword(s):  
Signal Transduction ◽  
Ion Channel ◽  
Cyclic Nucleotide
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