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.
J Physiol
2017 May 15;59510:3181-3202. doi: 10.1113/JP274015.
Show Gene links
Show Anatomy links
Protein kinase A regulates C-terminally truncated CaV 1.2 in Xenopus oocytes: roles of N- and C-termini of the α1C subunit.
Oz S
,
Pankonien I
,
Belkacemi A
,
Flockerzi V
,
Klussmann E
,
Haase H
,
Dascal N
.
???displayArticle.abstract???
KEY POINTS: β-Adrenergic stimulation enhances Ca2+ entry via L-type CaV 1.2 channels, causing stronger contraction of cardiac muscle cells. The signalling pathway involves activation of protein kinase A (PKA), but the molecular details of PKA regulation of CaV 1.2 remain controversial despite extensive research. We show that PKA regulation of CaV 1.2 can be reconstituted in Xenopus oocytes when the distal C-terminus (dCT) of the main subunit, α1C , is truncated. The PKA upregulation of CaV 1.2 does not require key factors previously implicated in this mechanism: the clipped dCT, the A kinase-anchoring protein 15 (AKAP15), the phosphorylation sites S1700, T1704 and S1928, or the β subunit of CaV 1.2. The gating element within the initial segment of the N-terminus of the cardiac isoform of α1C is essential for the PKA effect. We propose that the regulation described here is one of two or several mechanisms that jointly mediate the PKA regulation of CaV 1.2 in the heart.
ABSTRACT: β-Adrenergic stimulation enhances Ca2+ currents via L-type, voltage-gated CaV 1.2 channels, strengthening cardiac contraction. The signalling via β-adrenergic receptors (β-ARs) involves elevation of cyclic AMP (cAMP) levels and activation of protein kinase A (PKA). However, how PKA affects the channel remains controversial. Recent studies in heterologous systems and genetically engineered mice stress the importance of the post-translational proteolytic truncation of the distal C-terminus (dCT) of the main (α1C ) subunit. Here, we successfully reconstituted the cAMP/PKA regulation of the dCT-truncated CaV 1.2 in Xenopus oocytes, which previously failed with the non-truncated α1C . cAMP and the purified catalytic subunit of PKA, PKA-CS, injected into intact oocytes, enhanced CaV 1.2 currents by ∼40% (rabbit α1C ) to ∼130% (mouse α1C ). PKA blockers were used to confirm specificity and the need for dissociation of the PKA holoenzyme. The regulation persisted in the absence of the clipped dCT (as a separate protein), the A kinase-anchoring protein AKAP15, and the phosphorylation sites S1700 and T1704, previously proposed as essential for the PKA effect. The CaV β2b subunit was not involved, as suggested by extensive mutagenesis. Using deletion/chimeric mutagenesis, we have identified the initial segment of the cardiac long-N-terminal isoform of α1C as a previously unrecognized essential element involved in PKA regulation. We propose that the observed regulation, that exclusively involves the α1C subunit, is one of several mechanisms underlying the overall PKA action on CaV 1.2 in the heart. We hypothesize that PKA is acting on CaV 1.2, in part, by affecting a structural 'scaffold' comprising the interacting cytosolic N- and C-termini of α1C .
Abernethy,
Structure-functional diversity of human L-type Ca2+ channel: perspectives for new pharmacological targets.
2002, Pubmed
Abernethy,
Structure-functional diversity of human L-type Ca2+ channel: perspectives for new pharmacological targets.
2002,
Pubmed
Anand,
Cyclic AMP- and (Rp)-cAMPS-induced conformational changes in a complex of the catalytic and regulatory (RI{alpha}) subunits of cyclic AMP-dependent protein kinase.
2010,
Pubmed
Balijepalli,
Localization of cardiac L-type Ca(2+) channels to a caveolar macromolecular signaling complex is required for beta(2)-adrenergic regulation.
2006,
Pubmed
Bear,
Cl- channel activity in Xenopus oocytes expressing the cystic fibrosis gene.
1991,
Pubmed
,
Xenbase
Beavo,
Activation of protein kinase by physiological concentrations of cyclic AMP.
1974,
Pubmed
Benmocha Guggenheimer,
Interactions between N and C termini of α1C subunit regulate inactivation of CaV1.2 L-type Ca(2+) channel.
2016,
Pubmed
,
Xenbase
Bers,
Calcium fluxes involved in control of cardiac myocyte contraction.
2000,
Pubmed
Bers,
Calcium cycling and signaling in cardiac myocytes.
2008,
Pubmed
Biel,
Primary structure and functional expression of a high voltage activated calcium channel from rabbit lung.
1990,
Pubmed
,
Xenbase
Blumenstein,
A novel long N-terminal isoform of human L-type Ca2+ channel is up-regulated by protein kinase C.
2002,
Pubmed
,
Xenbase
Brandmayr,
Deletion of the C-terminal phosphorylation sites in the cardiac β-subunit does not affect the basic β-adrenergic response of the heart and the Ca(v)1.2 channel.
2012,
Pubmed
Bünemann,
Functional regulation of L-type calcium channels via protein kinase A-mediated phosphorylation of the beta(2) subunit.
1999,
Pubmed
Cachelin,
Ca2+ channel modulation by 8-bromocyclic AMP in cultured heart cells.
,
Pubmed
Campiglio,
The role of auxiliary subunits for the functional diversity of voltage-gated calcium channels.
2015,
Pubmed
Cantí,
Evidence for two concentration-dependent processes for beta-subunit effects on alpha1B calcium channels.
2001,
Pubmed
,
Xenbase
Carr,
Association of the type II cAMP-dependent protein kinase with a human thyroid RII-anchoring protein. Cloning and characterization of the RII-binding domain.
1992,
Pubmed
Catterall,
Structure and regulation of voltage-gated Ca2+ channels.
2000,
Pubmed
Catterall,
Regulation of Cardiac Calcium Channels in the Fight-or-Flight Response.
2015,
Pubmed
Charnet,
cAMP-dependent phosphorylation of the cardiac L-type Ca channel: a missing link?
1995,
Pubmed
,
Xenbase
Crump,
The cardiac L-type calcium channel distal carboxy terminus autoinhibition is regulated by calcium.
2013,
Pubmed
Csanády,
Preferential phosphorylation of R-domain Serine 768 dampens activation of CFTR channels by PKA.
2005,
Pubmed
,
Xenbase
Dai,
A new promoter for alpha1C subunit of human L-type cardiac calcium channel Ca(V)1.2.
2002,
Pubmed
Dema,
Pharmacological targeting of AKAP-directed compartmentalized cAMP signalling.
2015,
Pubmed
Dick,
A modular switch for spatial Ca2+ selectivity in the calmodulin regulation of CaV channels.
2008,
Pubmed
Dolphin,
Calcium channel auxiliary α2δ and β subunits: trafficking and one step beyond.
2012,
Pubmed
Domes,
Truncation of murine CaV1.2 at Asp-1904 results in heart failure after birth.
2011,
Pubmed
Florea,
The autonomic nervous system and heart failure.
2014,
Pubmed
Fraser,
A novel lipid-anchored A-kinase Anchoring Protein facilitates cAMP-responsive membrane events.
1998,
Pubmed
Frohnwieser,
Modulation of the human cardiac sodium channel alpha-subunit by cAMP-dependent protein kinase and the responsible sequence domain.
1997,
Pubmed
,
Xenbase
Fu,
Basal and β-adrenergic regulation of the cardiac calcium channel CaV1.2 requires phosphorylation of serine 1700.
2014,
Pubmed
Fu,
Deletion of the distal C terminus of CaV1.2 channels leads to loss of beta-adrenergic regulation and heart failure in vivo.
2011,
Pubmed
Fu,
Phosphorylation sites required for regulation of cardiac calcium channels in the fight-or-flight response.
2013,
Pubmed
Fuller,
Molecular mechanism of calcium channel regulation in the fight-or-flight response.
2010,
Pubmed
Fuller,
Differential regulation of CaV1.2 channels by cAMP-dependent protein kinase bound to A-kinase anchoring proteins 15 and 79/150.
2014,
Pubmed
Gadsby,
Control of CFTR channel gating by phosphorylation and nucleotide hydrolysis.
1999,
Pubmed
Ganesan,
Beta-adrenergic stimulation of L-type Ca2+ channels in cardiac myocytes requires the distal carboxyl terminus of alpha1C but not serine 1928.
2006,
Pubmed
Gao,
cAMP-dependent regulation of cardiac L-type Ca2+ channels requires membrane targeting of PKA and phosphorylation of channel subunits.
1997,
Pubmed
Gao,
C-terminal fragments of the alpha 1C (CaV1.2) subunit associate with and regulate L-type calcium channels containing C-terminal-truncated alpha 1C subunits.
2001,
Pubmed
Gerhardstein,
Proteolytic processing of the C terminus of the alpha(1C) subunit of L-type calcium channels and the role of a proline-rich domain in membrane tethering of proteolytic fragments.
2000,
Pubmed
Ginsburg,
Modulation of excitation-contraction coupling by isoproterenol in cardiomyocytes with controlled SR Ca2+ load and Ca2+ current trigger.
2004,
Pubmed
Haase,
In-vivo phosphorylation of the cardiac L-type calcium channel beta-subunit in response to catecholamines.
1996,
Pubmed
Han,
Effects of thyroid hormone on the calcium current and isoprenaline-induced background current in rabbit ventricular myocytes.
1994,
Pubmed
Hartzell,
Sympathetic regulation of cardiac calcium current is due exclusively to cAMP-dependent phosphorylation.
1991,
Pubmed
Hartzell,
Effects of protein phosphatase and kinase inhibitors on the cardiac L-type Ca current suggest two sites are phosphorylated by protein kinase A and another protein kinase.
1995,
Pubmed
Heubach,
L-type calcium current and contractility in ventricular myocytes from mice overexpressing the cardiac beta 2-adrenoceptor.
1999,
Pubmed
Hirayama,
Effects of protein phosphatase and kinase inhibitors on Ca2+ and Cl- currents in guinea pig ventricular myocytes.
1997,
Pubmed
Hofmann,
L-type CaV1.2 calcium channels: from in vitro findings to in vivo function.
2014,
Pubmed
Hulme,
Sites of proteolytic processing and noncovalent association of the distal C-terminal domain of CaV1.1 channels in skeletal muscle.
2005,
Pubmed
Hulme,
Autoinhibitory control of the CaV1.2 channel by its proteolytically processed distal C-terminal domain.
2006,
Pubmed
Ivanina,
Modulation of L-type Ca2+ channels by gbeta gamma and calmodulin via interactions with N and C termini of alpha 1C.
2000,
Pubmed
Jones,
Cardiomyocytes from AKAP7 knockout mice respond normally to adrenergic stimulation.
2012,
Pubmed
Kahanovitch,
Recruitment of Gβγ controls the basal activity of G-protein coupled inwardly rectifying potassium (GIRK) channels: crucial role of distal C terminus of GIRK1.
2014,
Pubmed
,
Xenbase
Kameyama,
Modulation of Ca current during the phosphorylation cycle in the guinea pig heart.
1986,
Pubmed
Kanevsky,
Regulation of maximal open probability is a separable function of Ca(v)beta subunit in L-type Ca2+ channel, dependent on NH2 terminus of alpha1C (Ca(v)1.2alpha).
2006,
Pubmed
,
Xenbase
Kim,
PKA-I holoenzyme structure reveals a mechanism for cAMP-dependent activation.
2007,
Pubmed
Kim,
Crystal structure of a complex between the catalytic and regulatory (RIalpha) subunits of PKA.
2005,
Pubmed
Klöckner,
Properties of three COOH-terminal splice variants of a human cardiac L-type Ca2+-channel alpha1-subunit.
1997,
Pubmed
,
Xenbase
Knighton,
Structure of a peptide inhibitor bound to the catalytic subunit of cyclic adenosine monophosphate-dependent protein kinase.
1991,
Pubmed
Koch,
cDNA cloning of a dihydropyridine-sensitive calcium channel from rat aorta. Evidence for the existence of alternatively spliced forms.
1990,
Pubmed
Lemke,
Unchanged beta-adrenergic stimulation of cardiac L-type calcium channels in Ca v 1.2 phosphorylation site S1928A mutant mice.
2008,
Pubmed
Liman,
Subunit stoichiometry of a mammalian K+ channel determined by construction of multimeric cDNAs.
1992,
Pubmed
,
Xenbase
Link,
Diversity and developmental expression of L-type calcium channel beta2 proteins and their influence on calcium current in murine heart.
2009,
Pubmed
Lynch,
RNA silencing identifies PDE4D5 as the functionally relevant cAMP phosphodiesterase interacting with beta arrestin to control the protein kinase A/AKAP79-mediated switching of the beta2-adrenergic receptor to activation of ERK in HEK293B2 cells.
2005,
Pubmed
Maltsev,
Establishment of beta-adrenergic modulation of L-type Ca2+ current in the early stages of cardiomyocyte development.
1999,
Pubmed
Matsuda,
Enhancement of the L-type Ca2+ current by mechanical stimulation in single rabbit cardiac myocytes.
1996,
Pubmed
McConnachie,
AKAP signaling complexes: getting to the heart of the matter.
2006,
Pubmed
Mikami,
Primary structure and functional expression of the cardiac dihydropyridine-sensitive calcium channel.
1989,
Pubmed
,
Xenbase
Minobe,
A new phosphorylation site in cardiac L-type Ca2+ channels (Cav1.2) responsible for its cAMP-mediated modulation.
2014,
Pubmed
Miriyala,
Role of CaVbeta subunits, and lack of functional reserve, in protein kinase A modulation of cardiac CaV1.2 channels.
2008,
Pubmed
Morrow,
Novel approaches to examine the regulation of voltage-gated calcium channels in the heart.
2015,
Pubmed
Nichols,
Sympathetic stimulation of adult cardiomyocytes requires association of AKAP5 with a subpopulation of L-type calcium channels.
2010,
Pubmed
Norman,
Subunit structure and phosphorylation of the cardiac L-type calcium channel.
1994,
Pubmed
Ohrtman,
Apparent lack of physical or functional interaction between CaV1.1 and its distal C terminus.
2015,
Pubmed
Olsen,
Isolation and characterization of cDNA clones for an inhibitor protein of cAMP-dependent protein kinase.
1991,
Pubmed
Osterrieder,
Injection of subunits of cyclic AMP-dependent protein kinase into cardiac myocytes modulates Ca2+ current.
1982,
Pubmed
Oz,
Competitive and non-competitive regulation of calcium-dependent inactivation in CaV1.2 L-type Ca2+ channels by calmodulin and Ca2+-binding protein 1.
2013,
Pubmed
,
Xenbase
Pang,
Tissue-specific expression of two human Ca(v)1.2 isoforms under the control of distinct 5' flanking regulatory elements.
2003,
Pubmed
Pankonien,
Ahnak1 interaction is affected by phosphorylation of Ser-296 on Cavβ₂.
2012,
Pubmed
Parsons,
Regulation of Ca2+ current in frog ventricular cardiomyocytes by 5'-guanylylimidodiphosphate and acetylcholine.
1991,
Pubmed
Patriarchi,
Phosphorylation of Cav1.2 on S1928 uncouples the L-type Ca2+ channel from the β2 adrenergic receptor.
2016,
Pubmed
Perez-Reyes,
Regulation of the cloned L-type cardiac calcium channel by cyclic-AMP-dependent protein kinase.
1994,
Pubmed
Reuter,
Properties of single calcium channels in cardiac cell culture.
1982,
Pubmed
Sako,
Modulation of cardiac Ca2+ channels by isoproterenol studied in transgenic mice with altered SR Ca2+ content.
1997,
Pubmed
Scott,
Amino acid sequence of the heat-stable inhibitor of the cAMP-dependent protein kinase from rabbit skeletal muscle.
1985,
Pubmed
Shannon,
Effects of triiodothyronine on retention of beta-adrenergic responsiveness of voltage-gated transmembrane calcium current during culture of ventricular myocytes from neonatal rabbits.
1995,
Pubmed
Shistik,
The N terminus of the cardiac L-type Ca(2+) channel alpha(1C) subunit. The initial segment is ubiquitous and crucial for protein kinase C modulation, but is not directly phosphorylated.
1999,
Pubmed
,
Xenbase
Shistik,
Crucial role of N terminus in function of cardiac L-type Ca2+ channel and its modulation by protein kinase C.
1998,
Pubmed
,
Xenbase
Simms,
The Cav1.2 N terminus contains a CaM kinase site that modulates channel trafficking and function.
2015,
Pubmed
Singer-Lahat,
Imaging plasma membrane proteins in large membrane patches of Xenopus oocytes.
2000,
Pubmed
,
Xenbase
Singer-Lahat,
Cardiac calcium channels expressed in Xenopus oocytes are modulated by dephosphorylation but not by cAMP-dependent phosphorylation.
1994,
Pubmed
,
Xenbase
Skeberdis,
Beta-2 adrenergic activation of L-type Ca++ current in cardiac myocytes.
1997,
Pubmed
Snutch,
Distinct calcium channels are generated by alternative splicing and are differentially expressed in the mammalian CNS.
1991,
Pubmed
,
Xenbase
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
Taylor,
Assembly of allosteric macromolecular switches: lessons from PKA.
2012,
Pubmed
Thomsen,
Transcriptional and electrophysiological consequences of KChIP2-mediated regulation of CaV1.2.
2009,
Pubmed
Trautwein,
The effect of intracellular cyclic nucleotides and calcium on the action potential and acetylcholine response of isolated cardiac cells.
1982,
Pubmed
Tröger,
A-kinase anchoring proteins as potential drug targets.
2012,
Pubmed
Uezono,
Receptors that couple to 2 classes of G proteins increase cAMP and activate CFTR expressed in Xenopus oocytes.
1993,
Pubmed
,
Xenbase
Viard,
PI3K promotes voltage-dependent calcium channel trafficking to the plasma membrane.
2004,
Pubmed
Vinogradova,
Regulation of basal and reserve cardiac pacemaker function by interactions of cAMP-mediated PKA-dependent Ca2+ cycling with surface membrane channels.
2009,
Pubmed
Walsh,
Krebs EG: Purification and characterization of a protein inhibitor of adenosine 3',5'-monophosphate-dependent protein kinases.
1971,
Pubmed
Wehrens,
Intracellular calcium release and cardiac disease.
2005,
Pubmed
Wei,
Modification of Ca2+ channel activity by deletions at the carboxyl terminus of the cardiac alpha 1 subunit.
1994,
Pubmed
,
Xenbase
Weiss,
Modulation of distinct isoforms of L-type calcium channels by G(q)-coupled receptors in Xenopus oocytes: antagonistic effects of Gβγ and protein kinase C.
2012,
Pubmed
,
Xenbase
Weiss,
Regulation of cardiac L-type Ca²⁺ channel CaV1.2 via the β-adrenergic-cAMP-protein kinase A pathway: old dogmas, advances, and new uncertainties.
2013,
Pubmed
Welsh,
Cystic fibrosis transmembrane conductance regulator: a chloride channel with novel regulation.
1992,
Pubmed
Wilkinson,
CFTR activation: additive effects of stimulatory and inhibitory phosphorylation sites in the R domain.
1997,
Pubmed
,
Xenbase
Yakubovich,
A Quantitative Model of the GIRK1/2 Channel Reveals That Its Basal and Evoked Activities Are Controlled by Unequal Stoichiometry of Gα and Gβγ.
2015,
Pubmed
,
Xenbase
Yang,
Loss of β-adrenergic-stimulated phosphorylation of CaV1.2 channels on Ser1700 leads to heart failure.
2016,
Pubmed
Yang,
β-adrenergic regulation of the L-type Ca2+ channel does not require phosphorylation of α1C Ser1700.
2013,
Pubmed
Yue,
Beta-adrenergic stimulation of calcium channels occurs by potentiation of high-activity gating modes.
1990,
Pubmed
Zong,
On the regulation of the expressed L-type calcium channel by cAMP-dependent phosphorylation.
1995,
Pubmed
