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.
Coexpression of cloned alpha(1B), beta(2a), and alpha(2)/delta subunits produces non-inactivating calcium currents similar to those found in bovine chromaffin cells.
Cahill AL
,
Hurley JH
,
Fox AP
.
???displayArticle.abstract???
Chromaffin cells express N-type calcium channels identified on the basis of their high sensitivity to block by omega-conotoxin GVIA (omega-CgTx GVIA). In contrast to neuronal N-type calcium currents that inactivate during long depolarizations and that require negative holding potentials to remove inactivation, many chromaffin cells exhibit N-type calcium channel currents that show little inactivation during maintained depolarizations and that exhibit no decrease in channel availability at depolarized holding potentials. N-type calcium channels are thought to be produced by combination of the pore-forming alpha(1B) subunit and accessory beta and alpha(2)/delta subunits. To examine the molecular composition of the non-inactivating N-type calcium channel, we cloned the alpha(1B) and accessory beta (beta(1b), beta(1c,) beta(2a), beta(2b), and beta(3a)) subunits found in bovine chromaffin cells. Expression of the subunits in either Xenopus oocytes or human embryonic kidney 293 cells produced high-threshold calcium currents that were blocked by omega-CgTx GVIA. Coexpression of bovine alpha(1B) with beta(1b), beta(1c), beta(2b), or beta(3a) produced currents that were holding potential dependent. In contrast, coexpression of bovine alpha(1B) with beta(2a) produced holding potential-independent calcium currents that closely mimicked native non-inactivating currents, suggesting that non-inactivating N-type channels consist of bovine alpha(1B), alpha(2)/delta, and beta(2a).
Albillos,
omega-Agatoxin-IVA-sensitive calcium channels in bovine chromaffin cells.
1993, Pubmed
Albillos,
omega-Agatoxin-IVA-sensitive calcium channels in bovine chromaffin cells.
1993,
Pubmed
Artalejo,
Omega-conotoxin GVIA blocks a Ca2+ current in bovine chromaffin cells that is not of the "classic" N type.
1992,
Pubmed
Artalejo,
Three types of Ca2+ channel trigger secretion with different efficacies in chromaffin cells.
1994,
Pubmed
Bezprozvanny,
Functional impact of syntaxin on gating of N-type and Q-type calcium channels.
1995,
Pubmed
,
Xenbase
Birnbaumer,
Structures and functions of calcium channel beta subunits.
1998,
Pubmed
,
Xenbase
Bourinet,
Splicing of alpha 1A subunit gene generates phenotypic variants of P- and Q-type calcium channels.
1999,
Pubmed
,
Xenbase
Cens,
Regulation of Ca-sensitive inactivation of a 1-type Ca2+ channel by specific domains of beta subunits.
1999,
Pubmed
,
Xenbase
Chien,
Identification of palmitoylation sites within the L-type calcium channel beta2a subunit and effects on channel function.
1996,
Pubmed
Collin,
Cloning, chromosomal location and functional expression of the human voltage-dependent calcium-channel beta 3 subunit.
1994,
Pubmed
,
Xenbase
Coppola,
Molecular cloning of a murine N-type calcium channel alpha 1 subunit. Evidence for isoforms, brain distribution, and chromosomal localization.
1994,
Pubmed
Cox,
Inactivation of N-type calcium current in chick sensory neurons: calcium and voltage dependence.
1994,
Pubmed
De Waard,
Subunit regulation of the neuronal alpha 1A Ca2+ channel expressed in Xenopus oocytes.
1995,
Pubmed
,
Xenbase
Dubel,
Molecular cloning of the alpha-1 subunit of an omega-conotoxin-sensitive calcium channel.
1992,
Pubmed
Dunlap,
Exocytotic Ca2+ channels in mammalian central neurons.
1995,
Pubmed
Ellinor,
Functional expression of a rapidly inactivating neuronal calcium channel.
1993,
Pubmed
,
Xenbase
Fujita,
Primary structure and functional expression of the omega-conotoxin-sensitive N-type calcium channel from rabbit brain.
1993,
Pubmed
Hamill,
Improved patch-clamp techniques for high-resolution current recording from cells and cell-free membrane patches.
1981,
Pubmed
Hans,
The blocking effects of omega-conotoxin on Ca current in bovine chromaffin cells.
1990,
Pubmed
Jones,
Overview of voltage-dependent calcium channels.
1998,
Pubmed
Lacerda,
Normalization of current kinetics by interaction between the alpha 1 and beta subunits of the skeletal muscle dihydropyridine-sensitive Ca2+ channel.
1991,
Pubmed
Letts,
The mouse stargazer gene encodes a neuronal Ca2+-channel gamma subunit.
1998,
Pubmed
Lin,
Identification of functionally distinct isoforms of the N-type Ca2+ channel in rat sympathetic ganglia and brain.
1997,
Pubmed
,
Xenbase
Lin,
Alternative splicing of a short cassette exon in alpha1B generates functionally distinct N-type calcium channels in central and peripheral neurons.
1999,
Pubmed
,
Xenbase
Mermelstein,
Properties of Q-type calcium channels in neostriatal and cortical neurons are correlated with beta subunit expression.
1999,
Pubmed
Olcese,
The amino terminus of a calcium channel beta subunit sets rates of channel inactivation independently of the subunit's effect on activation.
1994,
Pubmed
,
Xenbase
Page,
The intracellular loop between domains I and II of the B-type calcium channel confers aspects of G-protein sensitivity to the E-type calcium channel.
1997,
Pubmed
Parent,
Subunit regulation of the human brain alpha 1E calcium channel.
1997,
Pubmed
,
Xenbase
Patil,
Preferential closed-state inactivation of neuronal calcium channels.
1998,
Pubmed
Powers,
Skeletal muscle and brain isoforms of a beta-subunit of human voltage-dependent calcium channels are encoded by a single gene.
1992,
Pubmed
Qin,
Unique regulatory properties of the type 2a Ca2+ channel beta subunit caused by palmitoylation.
1998,
Pubmed
,
Xenbase
Sather,
Distinctive biophysical and pharmacological properties of class A (BI) calcium channel alpha 1 subunits.
1993,
Pubmed
,
Xenbase
Stanley,
Characterization of a calcium current in a vertebrate cholinergic presynaptic nerve terminal.
1991,
Pubmed
Stea,
A beta-subunit normalizes the electrophysiological properties of a cloned N-type Ca2+ channel alpha 1-subunit.
1993,
Pubmed
,
Xenbase
Takahashi,
Different types of calcium channels mediate central synaptic transmission.
1993,
Pubmed
Tareilus,
A Xenopus oocyte beta subunit: evidence for a role in the assembly/expression of voltage-gated calcium channels that is separate from its role as a regulatory subunit.
1997,
Pubmed
,
Xenbase
Turner,
Multiple Ca2+ channel types coexist to regulate synaptosomal neurotransmitter release.
1993,
Pubmed
Varadi,
Acceleration of activation and inactivation by the beta subunit of the skeletal muscle calcium channel.
1991,
Pubmed
Wheeler,
Roles of N-type and Q-type Ca2+ channels in supporting hippocampal synaptic transmission.
1994,
Pubmed
Williams,
Structure and functional expression of alpha 1, alpha 2, and beta subunits of a novel human neuronal calcium channel subtype.
1992,
Pubmed
,
Xenbase
Williams,
Structure and functional expression of an omega-conotoxin-sensitive human N-type calcium channel.
1992,
Pubmed
Zhang,
Molecular determinants of voltage-dependent inactivation in calcium channels.
1994,
Pubmed
,
Xenbase
