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Gating of heteromeric retinal rod channels by cyclic AMP: role of the C-terminal and pore domains.
Bennett N
,
Ildefonse M
,
Pagès F
,
Ragno M
.
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Cyclic nucleotide-gated channels are tetramers composed of homologous alpha and beta subunits. C-terminal truncation mutants of the alpha and beta subunits of the retinal rod channel were expressed in Xenopus oocytes, and analyzed for cGMP- and cAMP-induced currents (single-channel records and macroscopic currents). When the alpha subunit truncated downstream of the cGMP-binding site (alpha D608stop) is co-injected with truncated beta subunits, the heteromeric channels present a drastic increase of cAMP sensitivity. A partial effect is observed with heteromeric alpha R656stop-containing channels, while alpha K665stop-containing channels behave like alpha wt/beta wt. The three truncated alpha subunits have wild-type activity when expressed alone. Heteromeric channels composed of alpha wt or truncated alpha subunits and chimeric beta subunits containing the pore domain of the alpha subunit have the same cAMP sensitivity as alpha-only channels. The results disclose the key role of two domains distinct from the nucleotide binding site in the gating of heteromeric channels by cAMP: the pore of the beta subunit, which has an activating effect, and a conserved domain situated downstream of the cGMP-binding site in the alpha subunit (I609-K665), which inhibits this effect.
Becchetti,
Cyclic nucleotide-gated channels. Pore topology studied through the accessibility of reporter cysteines.
1999, Pubmed,
Xenbase
Becchetti,
Cyclic nucleotide-gated channels. Pore topology studied through the accessibility of reporter cysteines.
1999,
Pubmed
,
Xenbase
Becchetti,
Cyclic nucleotide-gated channels: intra- and extracellular accessibility to Cd2+ of substituted cysteine residues within the P-loop.
2000,
Pubmed
,
Xenbase
Biel,
Molecular cloning and expression of the Modulatory subunit of the cyclic nucleotide-gated cation channel.
1996,
Pubmed
Bradley,
Heteromeric olfactory cyclic nucleotide-gated channels: a subunit that confers increased sensitivity to cAMP.
1994,
Pubmed
Bucossi,
Time-dependent current decline in cyclic GMP-gated bovine channels caused by point mutations in the pore region expressed in Xenopus oocytes.
1996,
Pubmed
,
Xenbase
Bönigk,
The native rat olfactory cyclic nucleotide-gated channel is composed of three distinct subunits.
1999,
Pubmed
Chen,
A new subunit of the cyclic nucleotide-gated cation channel in retinal rods.
1993,
Pubmed
,
Xenbase
Corpet,
ProDom and ProDom-CG: tools for protein domain analysis and whole genome comparisons.
2000,
Pubmed
Cortes,
Molecular architecture of full-length KcsA: role of cytoplasmic domains in ion permeation and activation gating.
2001,
Pubmed
Doyle,
The structure of the potassium channel: molecular basis of K+ conduction and selectivity.
1998,
Pubmed
Eismann,
A single negative charge within the pore region of a cGMP-gated channel controls rectification, Ca2+ blockage, and ionic selectivity.
1994,
Pubmed
,
Xenbase
Flynn,
Conformational changes in S6 coupled to the opening of cyclic nucleotide-gated channels.
2001,
Pubmed
,
Xenbase
Gavazzo,
A point mutation in the pore region alters gating, Ca(2+) blockage, and permeation of olfactory cyclic nucleotide-gated channels.
2000,
Pubmed
,
Xenbase
Gerstner,
Molecular cloning and functional characterization of a new modulatory cyclic nucleotide-gated channel subunit from mouse retina.
2000,
Pubmed
Gordon,
Altered ligand specificity by protonation in the ligand binding domain of cyclic nucleotide-gated channels.
1996,
Pubmed
,
Xenbase
He,
Constraining the subunit order of rod cyclic nucleotide-gated channels reveals a diagonal arrangement of like subunits.
2000,
Pubmed
,
Xenbase
Johnson,
Rotational movement during cyclic nucleotide-gated channel opening.
2001,
Pubmed
,
Xenbase
Kaupp,
Primary structure and functional expression from complementary DNA of the rod photoreceptor cyclic GMP-gated channel.
1989,
Pubmed
,
Xenbase
Kohl,
Mutations in the CNGB3 gene encoding the beta-subunit of the cone photoreceptor cGMP-gated channel are responsible for achromatopsia (ACHM3) linked to chromosome 8q21.
2000,
Pubmed
Kozak,
Compilation and analysis of sequences upstream from the translational start site in eukaryotic mRNAs.
1984,
Pubmed
Kumar,
Molecular model of the cyclic GMP-binding domain of the cyclic GMP-gated ion channel.
1992,
Pubmed
Körschen,
A 240 kDa protein represents the complete beta subunit of the cyclic nucleotide-gated channel from rod photoreceptor.
1995,
Pubmed
Liman,
Subunit stoichiometry of a mammalian K+ channel determined by construction of multimeric cDNAs.
1992,
Pubmed
,
Xenbase
Liman,
A second subunit of the olfactory cyclic nucleotide-gated channel confers high sensitivity to cAMP.
1994,
Pubmed
,
Xenbase
Liu,
Subunit stoichiometry of cyclic nucleotide-gated channels and effects of subunit order on channel function.
1996,
Pubmed
Liu,
Constraining ligand-binding site stoichiometry suggests that a cyclic nucleotide-gated channel is composed of two functional dimers.
1998,
Pubmed
Liu,
Change of pore helix conformational state upon opening of cyclic nucleotide-gated channels.
2000,
Pubmed
,
Xenbase
Lupas,
Prediction and analysis of coiled-coil structures.
1996,
Pubmed
MONOD,
ON THE NATURE OF ALLOSTERIC TRANSITIONS: A PLAUSIBLE MODEL.
1965,
Pubmed
Pagès,
Coexpression of alpha and beta subunits of the rod cyclic GMP-gated channel restores native sensitivity to cyclic AMP: role of D604/N1201.
2000,
Pubmed
Passner,
Modeling the cAMP-induced allosteric transition using the crystal structure of CAP-cAMP at 2.1 A resolution.
2000,
Pubmed
Perozo,
Structural rearrangements underlying K+-channel activation gating.
1999,
Pubmed
Picco,
Modulation by internal protons of native cyclic nucleotide-gated channels from retinal rods.
1996,
Pubmed
Root,
Identification of an external divalent cation-binding site in the pore of a cGMP-activated channel.
1993,
Pubmed
,
Xenbase
Rost,
Prediction of protein secondary structure at better than 70% accuracy.
1993,
Pubmed
Rubin,
On the nature of allosteric transitions: implications of non-exclusive ligand binding.
1966,
Pubmed
Sautter,
An isoform of the rod photoreceptor cyclic nucleotide-gated channel beta subunit expressed in olfactory neurons.
1998,
Pubmed
Shabb,
Cyclic nucleotide-binding domains in proteins having diverse functions.
1992,
Pubmed
Shammat,
Stoichiometry and arrangement of subunits in rod cyclic nucleotide-gated channels.
1999,
Pubmed
,
Xenbase
Sundin,
Genetic basis of total colourblindness among the Pingelapese islanders.
2000,
Pubmed
Tanaka,
Photoreceptor channel activation by nucleotide derivatives.
1989,
Pubmed
Tibbs,
Allosteric activation and tuning of ligand efficacy in cyclic-nucleotide-gated channels.
1997,
Pubmed
,
Xenbase
Zagotta,
Structure and function of cyclic nucleotide-gated channels.
1996,
Pubmed