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.
Expression of the alpha(2)delta subunit interferes with prepulse facilitation in cardiac L-type calcium channels.
Platano D
,
Qin N
,
Noceti F
,
Birnbaumer L
,
Stefani E
,
Olcese R
.
???displayArticle.abstract???
We investigated the role of the accessory alpha(2)delta subunit on the voltage-dependent facilitation of cardiac L-type Ca(2+) channels (alpha(1C)). alpha(1C) Channels were coexpressed in Xenopus oocytes with beta(3) and alpha(2)delta calcium channel subunits. In alpha(1C) + beta(3), the amplitude of the ionic current (measured during pulses to 10 mV) was in average approximately 1.9-fold larger after the application of a 200-ms prepulse to +80 mV. This phenomenon, commonly referred to as voltage-dependent facilitation, was not observed when alpha(2)delta was coexpressed with alpha(1C) + beta(3). In alpha(1C) + beta(3), the prepulse produced a left shift ( approximately 40 mV) of the activation curve. Instead, the activation curve for alpha(1C) + beta(3) + alpha(2)delta was minimally affected by the prepulse and had a voltage dependence very similar to the G-V curve of the alpha(1C) + beta(3) channel facilitated by the prepulse. Coexpression of alpha(2)delta with alpha(1C) + beta(3) seems to mimic the prepulse effect by shifting the activation curve toward more negative potentials, leaving little room for facilitation. The facilitation of alpha(1C) + beta(3) was associated with an increase of the charge movement. In the presence of alpha(2)delta, the charge remained unaffected after the prepulse. Coexpression of alpha(2)delta seems to set all the channels in a conformational state from where the open state can be easily reached, even without prepulse.
Artalejo,
Three types of bovine chromaffin cell Ca2+ channels: facilitation increases the opening probability of a 27 pS channel.
1991, Pubmed
Artalejo,
Three types of bovine chromaffin cell Ca2+ channels: facilitation increases the opening probability of a 27 pS channel.
1991,
Pubmed
Bangalore,
Influence of L-type Ca channel alpha 2/delta-subunit on ionic and gating current in transiently transfected HEK 293 cells.
1996,
Pubmed
Barish,
A transient calcium-dependent chloride current in the immature Xenopus oocyte.
1983,
Pubmed
,
Xenbase
Bean,
Neurotransmitter inhibition of neuronal calcium currents by changes in channel voltage dependence.
1989,
Pubmed
Birnbaumer,
The naming of voltage-gated calcium channels.
1994,
Pubmed
Bourinet,
Voltage-dependent facilitation of a neuronal alpha 1C L-type calcium channel.
1994,
Pubmed
,
Xenbase
Cens,
Coexpression of the beta2 subunit does not induce voltage-dependent facilitation of the class C L-type Ca channel.
1996,
Pubmed
,
Xenbase
Cens,
Promotion and inhibition of L-type Ca2+ channel facilitation by distinct domains of the subunit.
1998,
Pubmed
,
Xenbase
Cloues,
Beta-adrenergic stimulation selectively inhibits long-lasting L-type calcium channel facilitation in hippocampal pyramidal neurons.
1997,
Pubmed
Costantin,
Long lasting facilitation of the rabbit cardiac Ca2+ channel: correlation with the coupling efficiency between charge movement and pore opening.
1998,
Pubmed
,
Xenbase
Dai,
The role of subunit composition on prepulse facilitation of the cardiac L-type calcium channel.
1999,
Pubmed
Dolphin,
Facilitation of Ca2+ current in excitable cells.
1996,
Pubmed
Fedida,
Mechanism of the use dependence of Ca2+ current in guinea-pig myocytes.
1988,
Pubmed
Felix,
Dissection of functional domains of the voltage-dependent Ca2+ channel alpha2delta subunit.
1997,
Pubmed
,
Xenbase
Gurnett,
Dual function of the voltage-dependent Ca2+ channel alpha 2 delta subunit in current stimulation and subunit interaction.
1996,
Pubmed
,
Xenbase
Ikeda,
Voltage-dependent modulation of N-type calcium channels by G-protein beta gamma subunits.
1996,
Pubmed
Johnson,
Voltage-dependent potentiation of L-type Ca2+ channels in skeletal muscle cells requires anchored cAMP-dependent protein kinase.
1994,
Pubmed
Kavalali,
Multiple voltage-dependent mechanisms potentiate calcium channel activity in hippocampal neurons.
1996,
Pubmed
Lee,
Potentiation of the calcium-channel currents of internally perfused mammalian heart cells by repetitive depolarization.
1987,
Pubmed
Neely,
Potentiation by the beta subunit of the ratio of the ionic current to the charge movement in the cardiac calcium channel.
1993,
Pubmed
,
Xenbase
Neely,
Ca(2+)-dependent inactivation of a cloned cardiac Ca2+ channel alpha 1 subunit (alpha 1C) expressed in Xenopus oocytes.
1994,
Pubmed
,
Xenbase
Noble,
The calcium and frequency dependence of the slow inward current 'staircase' in frog atrium.
1981,
Pubmed
Noble,
Voltage-dependent potentiation of the slow inward current in frog atrium.
1981,
Pubmed
Olcese,
Coupling between charge movement and pore opening in vertebrate neuronal alpha 1E calcium channels.
1996,
Pubmed
,
Xenbase
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
Perez-Reyes,
Cloning and expression of a cardiac/brain beta subunit of the L-type calcium channel.
1992,
Pubmed
,
Xenbase
Pietrobon,
Novel mechanism of voltage-dependent gating in L-type calcium channels.
1990,
Pubmed
Qin,
Direct interaction of gbetagamma with a C-terminal gbetagamma-binding domain of the Ca2+ channel alpha1 subunit is responsible for channel inhibition by G protein-coupled receptors.
1997,
Pubmed
,
Xenbase
Qin,
Unique regulatory properties of the type 2a Ca2+ channel beta subunit caused by palmitoylation.
1998,
Pubmed
,
Xenbase
Qin,
Modulation of human neuronal alpha 1E-type calcium channel by alpha 2 delta-subunit.
1998,
Pubmed
,
Xenbase
Rakowski,
Charge movement by the Na/K pump in Xenopus oocytes.
1993,
Pubmed
,
Xenbase
Sanford,
Gamma-subunits of G proteins, but not their alpha- or beta-subunits, are polyisoprenylated. Studies on post-translational modifications using in vitro translation with rabbit reticulocyte lysates.
1991,
Pubmed
Shirokov,
Inactivation of gating currents of L-type calcium channels. Specific role of the alpha 2 delta subunit.
1998,
Pubmed
Singer-Lahat,
Cardiac calcium channels expressed in Xenopus oocytes are modulated by dephosphorylation but not by cAMP-dependent phosphorylation.
1994,
Pubmed
,
Xenbase
Stefani,
Cut-open oocyte voltage-clamp technique.
1998,
Pubmed
,
Xenbase
Wei,
Increase in Ca2+ channel expression by deletions at the amino terminus of the cardiac alpha 1C subunit.
1996,
Pubmed
,
Xenbase
Wei,
Heterologous regulation of the cardiac Ca2+ channel alpha 1 subunit by skeletal muscle beta and gamma subunits. Implications for the structure of cardiac L-type Ca2+ channels.
1991,
Pubmed
,
Xenbase
Zygmunt,
Stimulation-dependent facilitation of the high threshold calcium current in guinea-pig ventricular myocytes.
1990,
Pubmed
