Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
Pflugers Arch
2017 Oct 01;46910:1335-1347. doi: 10.1007/s00424-017-2021-z.
Show Gene links
Show Anatomy links
Modulation of the FMRFamide-gated Na+ channel by external Ca2.
Fujimoto A
,
Kodani Y
,
Furukawa Y
.
???displayArticle.abstract???
FMRFamide-gated Na+ channel (FaNaC) is a member of the DEG/ENaC family. Amino acid sequence of the second transmembrane region (TM2) of FaNaC is quite similar to that of the acid-sensing ion channels (ASIC) of the same family. In the upper part of TM2, there are two aspartate residues (D552 and D556 in Aplysia FaNaC, AkFaNaC) which construct two negative rings in the external vestibule. In the present study, we examined the function of D552/D556 mutants of AkFaNaC in Xenopus oocytes with special interest in Ca2+ sensitivity of FaNaC. The FMRFamide-evoked current through AkFaNaC was depressed by submillimolar Ca2+ such that the current in Ca2+-free condition was 2-3-fold larger than that in the control solution which contained 1.8 mM CaCl 2. Both D552 and D556 were found to be indispensable for the sensitivity of FaNaC to submillimolar Ca2+. Unexpectedly, however, both acidic residues were not essential for the inhibition by millimolar Ca2+ concentrations. The Ca2+-sensitive gating of FaNaC was recapitulated by an allosteric model in which Ca2+-bound channels are more difficult to open. The desensitization of FaNaC was also inhibited by Ca2+, which was abolished in some D552/D556 mutants. Structural models of FaNaC made by homology modeling showed that the distance between oxygen atoms of D552 and D556 on the adjacent subunits is close enough to coordinate Ca2+ in the nonconducting desensitized channel but not in the open channel. The results suggest that Ca2+ coordination between oxygen atoms of D552 and D556 disturbs the opening transition as well as the desensitization of FaNaC.
Babini,
Alternative splicing and interaction with di- and polyvalent cations control the dynamic range of acid-sensing ion channel 1 (ASIC1).
2002, Pubmed,
Xenbase
Babini,
Alternative splicing and interaction with di- and polyvalent cations control the dynamic range of acid-sensing ion channel 1 (ASIC1).
2002,
Pubmed
,
Xenbase
Baconguis,
X-ray structure of acid-sensing ion channel 1-snake toxin complex reveals open state of a Na(+)-selective channel.
2014,
Pubmed
Boscardin,
The function and regulation of acid-sensing ion channels (ASICs) and the epithelial Na(+) channel (ENaC): IUPHAR Review 19.
2016,
Pubmed
Cottrell,
The neuropeptide Phe-Met-Arg-Phe-NH2 (FMRFamide) can activate a ligand-gated ion channel in Helix neurones.
1990,
Pubmed
Driscoll,
The mec-4 gene is a member of a family of Caenorhabditis elegans genes that can mutate to induce neuronal degeneration.
1991,
Pubmed
Dürrnagel,
Three homologous subunits form a high affinity peptide-gated ion channel in Hydra.
2010,
Pubmed
,
Xenbase
Dürrnagel,
High Ca(2+) permeability of a peptide-gated DEG/ENaC from Hydra.
2012,
Pubmed
,
Xenbase
Furukawa,
Molecular cloning and functional characterization of the Aplysia FMRFamide-gated Na+ channel.
2006,
Pubmed
,
Xenbase
Golubovic,
A peptide-gated ion channel from the freshwater polyp Hydra.
2007,
Pubmed
Gonzales,
Pore architecture and ion sites in acid-sensing ion channels and P2X receptors.
2009,
Pubmed
Gründer,
Peptide-gated ion channels and the simple nervous system of Hydra.
2015,
Pubmed
Hidalgo,
Revealing the architecture of a K+ channel pore through mutant cycles with a peptide inhibitor.
1995,
Pubmed
,
Xenbase
Horovitz,
Double-mutant cycles: a powerful tool for analyzing protein structure and function.
1996,
Pubmed
Immke,
Protons open acid-sensing ion channels by catalyzing relief of Ca2+ blockade.
2003,
Pubmed
Jasti,
Structure of acid-sensing ion channel 1 at 1.9 A resolution and low pH.
2007,
Pubmed
Jeziorski,
Cloning and expression of a FMRFamide-gated Na(+) channel from Helisoma trivolvis and comparison with the native neuronal channel.
2000,
Pubmed
,
Xenbase
Kellenberger,
A single point mutation in the pore region of the epithelial Na+ channel changes ion selectivity by modifying molecular sieving.
1999,
Pubmed
,
Xenbase
Kellenberger,
On the molecular basis of ion permeation in the epithelial Na+ channel.
1999,
Pubmed
,
Xenbase
Kodani,
Position 552 in a FMRFamide-gated Na(+) channel affects the gating properties and the potency of FMRFamide.
2010,
Pubmed
,
Xenbase
Kodani,
Electrostatic charge at position 552 affects the activation and permeation of FMRFamide-gated Na+ channels.
2014,
Pubmed
,
Xenbase
Krissinel,
Inference of macromolecular assemblies from crystalline state.
2007,
Pubmed
Lefèvre,
Pharmacological and electrophysiological characterization of the human bile acid-sensitive ion channel (hBASIC).
2014,
Pubmed
Li,
Asp433 in the closing gate of ASIC1 determines stability of the open state without changing properties of the selectivity filter or Ca2+ block.
2011,
Pubmed
,
Xenbase
Li,
Outlines of the pore in open and closed conformations describe the gating mechanism of ASIC1.
2011,
Pubmed
,
Xenbase
Lingueglia,
Cloning of the amiloride-sensitive FMRFamide peptide-gated sodium channel.
1995,
Pubmed
,
Xenbase
Lingueglia,
FMRFamide-gated sodium channel and ASIC channels: a new class of ionotropic receptors for FMRFamide and related peptides.
2006,
Pubmed
MONOD,
ON THE NATURE OF ALLOSTERIC TRANSITIONS: A PLAUSIBLE MODEL.
1965,
Pubmed
Paukert,
Candidate amino acids involved in H+ gating of acid-sensing ion channel 1a.
2008,
Pubmed
,
Xenbase
Paukert,
Identification of the Ca2+ blocking site of acid-sensing ion channel (ASIC) 1: implications for channel gating.
2004,
Pubmed
,
Xenbase
Perry,
Neuronal expression of an FMRFamide-gated Na+ channel and its modulation by acid pH.
2001,
Pubmed
Sakai,
Cloning and functional expression of a novel degenerin-like Na+ channel gene in mammals.
1999,
Pubmed
,
Xenbase
Sali,
Comparative protein modelling by satisfaction of spatial restraints.
1993,
Pubmed
Wang,
Towards predicting Ca2+-binding sites with different coordination numbers in proteins with atomic resolution.
2009,
Pubmed
Wiemuth,
The bile acid-sensitive ion channel (BASIC), the ignored cousin of ASICs and ENaC.
2014,
Pubmed
Wiemuth,
A single amino acid tunes Ca2+ inhibition of brain liver intestine Na+ channel (BLINaC).
2010,
Pubmed
,
Xenbase
Zhainazarov,
Single-channel currents of a peptide-gated sodium channel expressed in Xenopus oocytes.
1998,
Pubmed
,
Xenbase
Zhang,
Gating of acid-sensitive ion channel-1: release of Ca2+ block vs. allosteric mechanism.
2006,
Pubmed
,
Xenbase
