Dear Maedeh,

Indeed it is. Attached please find some publications on this topic.

1-Calmodulin interactions with Cav1 and Cav2

voltage-gated calcium channel IQ domains

Eun Young Kim†, Felix Findeisen† and Daniel L Minor†,‡,§,§§

2-Mol Pharmacol. 1992 Sep;42(3):489-8.

Inhibition of voltage-gated Ca2+ channels and insulin secretion in HIT cells by the Ca2+/calmodulin-dependent protein kinase II inhibitor KN-62: comparison with antagonists of calmodulin and L-type Ca2+ channels.

Li G1, Hidaka H, Wollheim CB.

Author information

Abstract

To probe for the involvement of Ca2+/calmodulin-dependent protein kinase II in the regulation of insulin secretion, the effects of a specific inhibitor of this enzyme, KN-62, on secretagogue-stimulated insulin secretion, cytosolic Ca2+ concentration ([Ca2+]i) rise, membrane depolarization, and nutrient metabolism were examined in HIT-T15 cells. KN-62 dose-dependently inhibited insulin secretion induced by a nutrient mixture (10 mM glucose, 5 mM leucine, and 5 mM glutamine) alone or combined with either the Ca(2+)-mobilizing receptor agonist bombesin or the cAMP-raising agent forskolin in intact cells. KN-62 did not affect Ca(2+)- or GTP analogue-induced insulin secretion from permeabilized cells, indicating an action at a step before exocytosis. The stimulating effects of nutrients on insulin secretion, [Ca2+]i, and membrane depolarization were potentiated by bombesin. Similarly, bombesin promoted a larger depolarization and [Ca2+]i rise in the presence of nutrients. This was associated with enhanced Ca2+ mobilization and the appearance of sustained [Ca2+]i elevation. The bombesin-induced membrane depolarization, like the nutrient effect, was inhibited by diazoxide, suggesting that this is due to closure of ATP-sensitive K+ channels. Bombesin elicited Ca2+ influx by both membrane potential-sensitive and -insensitive conductance pathways. KN-62 did not affect Ca2+ mobilization and only partially reduced Ca2+ entry during the sustained [Ca2+]i rise in bombesin-stimulated cells. When added before or during the stimulation, KN-62 dose-dependently inhibited nutrient- and KCl-stimulated [Ca2+]i elevation and Mn2+ influx (reflecting Ca2+ entry). The calmodulin antagonist CGS 9343B and the L-type Ca2+ channel blocker SR-7037 mimicked the inhibitory effect of KN-62 on stimulated insulin secretion and [Ca2+]i elevation. Membrane depolarization and nutrient metabolism (reduction of a tetrazolium derivative), however, were not altered by KN-62 treatment, indicating that the early coupling events from nutrient metabolism to closure of ATP-sensitive K+ channels remain operative. These results suggest that KN-62 and the calmodulin antagonist CGS 9343B inhibit Ca2+ influx by means of direct interaction with L-type Ca2+ channels, which, in turn, causes inhibition of stimulated insulin secretion. Thus, it appears that Ca2+/calmodulin-dependent protein kinase II is not involved in the regulation of insulin secretion.

3-Review: Calmodulin regulation (calmodulation) of voltage-gated calcium channels

Manu Ben-Johny1,2,3,4 and

David T. Yue1,2,3,4

1Calcium Signals Laboratory, 2Department of Biomedical Engineering, 3Department of Neuroscience, and 4Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205

Correspondence to David T. Yue: dyue{at}jhmi.edu

ABSTRACT

Calmodulin regulation (calmodulation) of the family of voltage-gated CaV1-2 channels comprises a prominent prototype for ion channel regulation, remarkable for its powerful Ca2+ sensing capabilities, deep in elegant mechanistic lessons, and rich in biological and therapeutic implications. This field thereby resides squarely at the epicenter of Ca2+ signaling biology, ion channel biophysics, and therapeutic advance. This review summarizes the historical development of ideas in this field, the scope and richly patterned organization of Ca2+ feedback behaviors encompassed by this system, and the long-standing challenges and recent developments in discerning a molecular basis for calmodulation. We conclude by highlighting the considerable synergy between mechanism, biological insight, and promising therapeutics.

The ancient Ca2+ sensor protein calmodulin (CaM) has emerged as a pervasive modulator of ion channels (Saimi and Kung, 2002), manifesting remarkable Ca2+ sensing capabilities in this context (Dunlap, 2007; Tadross et al., 2008) and furnishing essential Ca2+ feedback in numerous biological settings (Alseikhan et al., 2002; Xu and Wu, 2005; Mahajan et al., 2008; Adams et al., 2010; Morotti et al., 2012). Such modulation was discovered via mutations in CaM that altered the motile behavior of Paramecium, stemming from blunted activation of Ca2+-dependent Na+ current or K+ current (Kink et al., 1990). Since then, numerous ion channels have been found to be modulated by CaM, as extensively reviewed (Budde et al., 2002; Saimi and Kung, 2002; Wei et al., 2003; Halling et al., 2006; Tan et al., 2011; Nyegaard et al., 2012). This paper focuses on the CaM regulation (calmodulation) of voltage-gated Ca2+ channels, which are extensively regulated by intracellular Ca2+ binding to CaM (Ca2+/CaM; Lee et al., 1999; Peterson et al., 1999;Zühlke et al., 1999; Haeseleer et al., 2000; DeMaria et al., 2001; Budde et al., 2002;Halling et al., 2006). Such feedback regulation by Ca2+/CaM demonstrates versatile functional capabilities, represents a prominent prototype for ion-channel modulation, and holds far-reaching biological consequences. These attributes contribute much to the standing of voltage-gated Ca2+ channels as the queen of ion channels, molecules that not only sculpt membrane electrical waveforms but also serve as gatekeepers of the ubiquitous second messenger Ca2+ (Yue, 2004).

4- Original ArticleGenetics

Ca2+/Calmodulin-Dependent Protein Kinase II–Based Regulation of Voltage-Gated Na+ Channel in Cardiac Disease

Olha M. Koval, PhD*;

Jedidiah S. Snyder, BS*;

Roseanne M. Wolf, PhD;

Ryan E. Pavlovicz, BS;

Patric Glynn, BS;

Jerry Curran, PhD;

Nicholas D. Leymaster, MS;

Wen Dun, MD, PhD;

Patrick J. Wright, BS;

Natalia Cardona;

Lan Qian, MD;

Colleen C. Mitchell, PhD;

Penelope A. Boyden, PhD;

Philip F. Binkley, MD;

Chenglong Li, PhD;

Mark E. Anderson, MD, PhD;

Peter J. Mohler, PhD;

Thomas J. Hund, PhD

+Author Affiliations

From The Dorothy M. Davis Heart and Lung Research Institute (O.M.K., J.S.S., R.M.W., R.E.P., P.G., J.C., P.J.W., P.F.B., C.L., P.J.M., T.J.H.), Department of Biomedical Engineering, College of Engineering (J.S.S., P.G., T.J.H.), Division of Medicinal Chemistry and Pharmocognosy, College of Pharmacy (R.E.P., C.L.), Department of Internal Medicine (P.F.B., P.J.M., T.J.H.), and Department of Physiology and Cell Biology (P.J.M.), Ohio State University Medical Center, Columbus; Department of Internal Medicine (O.M.K., L.Q., M.E.A.) and Department of Molecular Physiology and Biophysics (D.L., N.C., M.E.A.), University of Iowa Carver College of Medicine, Iowa City; Department of Mathematics, University of Iowa, Iowa City (R.M.W., C.C.M.); and Department of Pharmacology, Center for Molecular Therapeutics, Columbia University, New York, NY (W.D., P.A.B.).

Correspondence to Thomas J. Hund, PhD, The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Medical Center, 473 W 12th Ave, Columbus, OH 43210. E-mail [email protected]

↵* Dr Koval and J.S. Snyder contributed equally to this article.

Next Section

Abstract

Background—Human gene variants affecting ion channel biophysical activity and/or membrane localization are linked to potentially fatal cardiac arrhythmias. However, the mechanism for many human arrhythmia variants remains undefined despite more than a decade of investigation. Posttranslational modulation of membrane proteins is essential for normal cardiac function. Importantly, aberrant myocyte signaling has been linked to defects in cardiac ion channel posttranslational modifications and disease. We recently identified a novel pathway for posttranslational regulation of the primary cardiac voltage-gated Na+ channel (Nav1.5) by Ca2+/calmodulin-dependent protein kinase II (CaMKII). However, a role for this pathway in cardiac disease has not been evaluated.

Methods and Results—We evaluated the role of CaMKII-dependent phosphorylation in human genetic and acquired disease. We report an unexpected link between a short motif in the Nav1.5 DI-DII loop, recently shown to be critical for CaMKII-dependent phosphorylation, and Nav1.5 function in monogenic arrhythmia and common heart disease. Experiments in heterologous cells and primary ventricular cardiomyocytes demonstrate that the human arrhythmia susceptibility variants (A572D and Q573E) alter CaMKII-dependent regulation of Nav1.5, resulting in abnormal channel activity and cell excitability. In silico analysis reveals that these variants functionally mimic the phosphorylated channel, resulting in increased susceptibility to arrhythmia-triggering afterdepolarizations. Finally, we report that this same motif is aberrantly regulated in a large-animal model of acquired heart disease and in failing human myocardium.

Conclusions—We identify the mechanism for 2 human arrhythmia variants that affect Nav1.5 channel activity through direct effects on channel posttranslational modification. We propose that the CaMKII phosphorylation motif in the Nav1.5 DI-DII cytoplasmic loop is a critical nodal point for proarrhythmic changes to Nav1.5 in congenital and acquired cardiac disease.

Hoping this will be helpful,

Rafik

Dear Maedeh,

Indeed it is. Attached please find some publications on this topic.

1-Calmodulin interactions with Cav1 and Cav2

voltage-gated calcium channel IQ domains

Eun Young Kim†, Felix Findeisen† and Daniel L Minor†,‡,§,§§

2-Mol Pharmacol. 1992 Sep;42(3):489-8.

Inhibition of voltage-gated Ca2+ channels and insulin secretion in HIT cells by the Ca2+/calmodulin-dependent protein kinase II inhibitor KN-62: comparison with antagonists of calmodulin and L-type Ca2+ channels.

Li G1, Hidaka H, Wollheim CB.

Author information

Abstract

To probe for the involvement of Ca2+/calmodulin-dependent protein kinase II in the regulation of insulin secretion, the effects of a specific inhibitor of this enzyme, KN-62, on secretagogue-stimulated insulin secretion, cytosolic Ca2+ concentration ([Ca2+]i) rise, membrane depolarization, and nutrient metabolism were examined in HIT-T15 cells. KN-62 dose-dependently inhibited insulin secretion induced by a nutrient mixture (10 mM glucose, 5 mM leucine, and 5 mM glutamine) alone or combined with either the Ca(2+)-mobilizing receptor agonist bombesin or the cAMP-raising agent forskolin in intact cells. KN-62 did not affect Ca(2+)- or GTP analogue-induced insulin secretion from permeabilized cells, indicating an action at a step before exocytosis. The stimulating effects of nutrients on insulin secretion, [Ca2+]i, and membrane depolarization were potentiated by bombesin. Similarly, bombesin promoted a larger depolarization and [Ca2+]i rise in the presence of nutrients. This was associated with enhanced Ca2+ mobilization and the appearance of sustained [Ca2+]i elevation. The bombesin-induced membrane depolarization, like the nutrient effect, was inhibited by diazoxide, suggesting that this is due to closure of ATP-sensitive K+ channels. Bombesin elicited Ca2+ influx by both membrane potential-sensitive and -insensitive conductance pathways. KN-62 did not affect Ca2+ mobilization and only partially reduced Ca2+ entry during the sustained [Ca2+]i rise in bombesin-stimulated cells. When added before or during the stimulation, KN-62 dose-dependently inhibited nutrient- and KCl-stimulated [Ca2+]i elevation and Mn2+ influx (reflecting Ca2+ entry). The calmodulin antagonist CGS 9343B and the L-type Ca2+ channel blocker SR-7037 mimicked the inhibitory effect of KN-62 on stimulated insulin secretion and [Ca2+]i elevation. Membrane depolarization and nutrient metabolism (reduction of a tetrazolium derivative), however, were not altered by KN-62 treatment, indicating that the early coupling events from nutrient metabolism to closure of ATP-sensitive K+ channels remain operative. These results suggest that KN-62 and the calmodulin antagonist CGS 9343B inhibit Ca2+ influx by means of direct interaction with L-type Ca2+ channels, which, in turn, causes inhibition of stimulated insulin secretion. Thus, it appears that Ca2+/calmodulin-dependent protein kinase II is not involved in the regulation of insulin secretion.

3-Review: Calmodulin regulation (calmodulation) of voltage-gated calcium channels

Manu Ben-Johny1,2,3,4 and

David T. Yue1,2,3,4

1Calcium Signals Laboratory, 2Department of Biomedical Engineering, 3Department of Neuroscience, and 4Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205

Correspondence to David T. Yue: dyue{at}jhmi.edu

ABSTRACT

Calmodulin regulation (calmodulation) of the family of voltage-gated CaV1-2 channels comprises a prominent prototype for ion channel regulation, remarkable for its powerful Ca2+ sensing capabilities, deep in elegant mechanistic lessons, and rich in biological and therapeutic implications. This field thereby resides squarely at the epicenter of Ca2+ signaling biology, ion channel biophysics, and therapeutic advance. This review summarizes the historical development of ideas in this field, the scope and richly patterned organization of Ca2+ feedback behaviors encompassed by this system, and the long-standing challenges and recent developments in discerning a molecular basis for calmodulation. We conclude by highlighting the considerable synergy between mechanism, biological insight, and promising therapeutics.

The ancient Ca2+ sensor protein calmodulin (CaM) has emerged as a pervasive modulator of ion channels (Saimi and Kung, 2002), manifesting remarkable Ca2+ sensing capabilities in this context (Dunlap, 2007; Tadross et al., 2008) and furnishing essential Ca2+ feedback in numerous biological settings (Alseikhan et al., 2002; Xu and Wu, 2005; Mahajan et al., 2008; Adams et al., 2010; Morotti et al., 2012). Such modulation was discovered via mutations in CaM that altered the motile behavior of Paramecium, stemming from blunted activation of Ca2+-dependent Na+ current or K+ current (Kink et al., 1990). Since then, numerous ion channels have been found to be modulated by CaM, as extensively reviewed (Budde et al., 2002; Saimi and Kung, 2002; Wei et al., 2003; Halling et al., 2006; Tan et al., 2011; Nyegaard et al., 2012). This paper focuses on the CaM regulation (calmodulation) of voltage-gated Ca2+ channels, which are extensively regulated by intracellular Ca2+ binding to CaM (Ca2+/CaM; Lee et al., 1999; Peterson et al., 1999;Zühlke et al., 1999; Haeseleer et al., 2000; DeMaria et al., 2001; Budde et al., 2002;Halling et al., 2006). Such feedback regulation by Ca2+/CaM demonstrates versatile functional capabilities, represents a prominent prototype for ion-channel modulation, and holds far-reaching biological consequences. These attributes contribute much to the standing of voltage-gated Ca2+ channels as the queen of ion channels, molecules that not only sculpt membrane electrical waveforms but also serve as gatekeepers of the ubiquitous second messenger Ca2+ (Yue, 2004).

4- Original ArticleGenetics

Ca2+/Calmodulin-Dependent Protein Kinase II–Based Regulation of Voltage-Gated Na+ Channel in Cardiac Disease

Olha M. Koval, PhD*;

Jedidiah S. Snyder, BS*;

Roseanne M. Wolf, PhD;

Ryan E. Pavlovicz, BS;

Patric Glynn, BS;

Jerry Curran, PhD;

Nicholas D. Leymaster, MS;

Wen Dun, MD, PhD;

Patrick J. Wright, BS;

Natalia Cardona;

Lan Qian, MD;

Colleen C. Mitchell, PhD;

Penelope A. Boyden, PhD;

Philip F. Binkley, MD;

Chenglong Li, PhD;

Mark E. Anderson, MD, PhD;

Peter J. Mohler, PhD;

Thomas J. Hund, PhD

+Author Affiliations

From The Dorothy M. Davis Heart and Lung Research Institute (O.M.K., J.S.S., R.M.W., R.E.P., P.G., J.C., P.J.W., P.F.B., C.L., P.J.M., T.J.H.), Department of Biomedical Engineering, College of Engineering (J.S.S., P.G., T.J.H.), Division of Medicinal Chemistry and Pharmocognosy, College of Pharmacy (R.E.P., C.L.), Department of Internal Medicine (P.F.B., P.J.M., T.J.H.), and Department of Physiology and Cell Biology (P.J.M.), Ohio State University Medical Center, Columbus; Department of Internal Medicine (O.M.K., L.Q., M.E.A.) and Department of Molecular Physiology and Biophysics (D.L., N.C., M.E.A.), University of Iowa Carver College of Medicine, Iowa City; Department of Mathematics, University of Iowa, Iowa City (R.M.W., C.C.M.); and Department of Pharmacology, Center for Molecular Therapeutics, Columbia University, New York, NY (W.D., P.A.B.).

Correspondence to Thomas J. Hund, PhD, The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Medical Center, 473 W 12th Ave, Columbus, OH 43210. E-mail [email protected]

↵* Dr Koval and J.S. Snyder contributed equally to this article.

Next Section

Abstract

Background—Human gene variants affecting ion channel biophysical activity and/or membrane localization are linked to potentially fatal cardiac arrhythmias. However, the mechanism for many human arrhythmia variants remains undefined despite more than a decade of investigation. Posttranslational modulation of membrane proteins is essential for normal cardiac function. Importantly, aberrant myocyte signaling has been linked to defects in cardiac ion channel posttranslational modifications and disease. We recently identified a novel pathway for posttranslational regulation of the primary cardiac voltage-gated Na+ channel (Nav1.5) by Ca2+/calmodulin-dependent protein kinase II (CaMKII). However, a role for this pathway in cardiac disease has not been evaluated.

Methods and Results—We evaluated the role of CaMKII-dependent phosphorylation in human genetic and acquired disease. We report an unexpected link between a short motif in the Nav1.5 DI-DII loop, recently shown to be critical for CaMKII-dependent phosphorylation, and Nav1.5 function in monogenic arrhythmia and common heart disease. Experiments in heterologous cells and primary ventricular cardiomyocytes demonstrate that the human arrhythmia susceptibility variants (A572D and Q573E) alter CaMKII-dependent regulation of Nav1.5, resulting in abnormal channel activity and cell excitability. In silico analysis reveals that these variants functionally mimic the phosphorylated channel, resulting in increased susceptibility to arrhythmia-triggering afterdepolarizations. Finally, we report that this same motif is aberrantly regulated in a large-animal model of acquired heart disease and in failing human myocardium.

Conclusions—We identify the mechanism for 2 human arrhythmia variants that affect Nav1.5 channel activity through direct effects on channel posttranslational modification. We propose that the CaMKII phosphorylation motif in the Nav1.5 DI-DII cytoplasmic loop is a critical nodal point for proarrhythmic changes to Nav1.5 in congenital and acquired cardiac disease.

Hoping this will be helpful,

Rafik

Thank you very much Rafik. I really appreciate your time and effort. All of these publications were extremely useful to me.

Thanks again

Best regards,

Maedeh