Regulation of Calcium Channels by G Protein-Coupled Receptors

Em

extracellular modulators

intracellular modulators

+

+

+

Ca2+

enzymesexcitation-contraction

genetranscription

membranepotential

exocytosis

GABA NE

Transmitters decrease the calcium componentof sensory neurone action potentials

Dunlap K, Fischbach GD. Neurotransmitters decrease the calcium component of sensory neurone action potentials. Nature. 1978 Dec;276(5690):837-839.

Calcium channels are multimeric proteins

S1 S2 S3

S4S5S6

+++++

S

SSS

Strock J, Diverse-Pierluissi MA. Ca2+ channels as integrators of G protein-mediated signaling in neurons. Mol Pharmacol. 2004 Nov;66(5):1071-1076. Epub 2004 Jul 21.

Cav1.1 L a1S DHP Skeletal muscle Excitation-contraction, Gene regulation

Cav1.2 L a1C DHP Heart, endo., neurons Excitation-contraction, Hormone secretion

Cav1.3 L a1D DHP Endocrine cells and neurons Hormone secretion, Gene regulation

Cav1.4 L a1F Retina Tonic transmitter release

Cav2.1 P/Q a1A -Ag Neurons Exocytosis

Cav2.2 N a1B -Con Neurons Exocytosis

Cav2.3 R a1E SNX482 Neurons Exocytosis

Name Previous Alpha 1 Blocker Localization Function Name

Classification of high-voltage activated calcium channels

Strock J, Diverse-Pierluissi MA. Ca2+ channels as integrators of G protein-mediated signaling in neurons. Mol Pharmacol. 2004 Nov;66(5):1071-1076. Epub 2004 Jul 21.

Active zones contain calcium channels and synaptic vesicles that interact with adaptor proteins

Multiple G protein-mediated pathways inhibit voltage-dependent calcium channels

Strock J, Diverse-Pierluissi MA. Ca2+ channels as integrators of G protein-mediated signaling in neurons. Mol Pharmacol. 2004 Nov;66(5):1071-1076. Epub 2004 Jul 21.

IVI II III

N-terminus loop I-II

loop II-III: synprint (aa-726-984)

loop II-III: remainder (985-1170)

C-terminus (aa 1916-2375)

Cytoplasmic domains of the alpha 1 subunit of the calcium channel

IVI II III

181

MuncMint-1

SNAP25

synap.

syntaxin

Proteins that interact with the cytoplasmic domains of the alpha 1 subunit of the calcium

channel can interact with each other

Proteins that interact with the cytoplasmic domains of the alpha 1 subunit of the calcium channel

Strock J, Diverse-Pierluissi MA. Ca2+ channels as integrators of G protein-mediated signaling in neurons. Mol Pharmacol. 2004 Nov;66(5):1071-1076. Epub 2004 Jul 21.

*

Inhibition of N type calcium current has two components

200 pA

10 ms

*NE

CON*

*-80 mV

+80 mV

0 mV

* prepulse to +80mV

*

**

voltage-dependent voltage-independent

Interaction of Gwith the calcium channel mediates transmitter-induced voltage-

dependent inhibition of calcium current

Jarvis SE, Zamponi GW. Interactions between presynaptic Ca2+ channels, cytoplasmic messengers and proteins of the synaptic vesicle release complex. Trends Pharmacol Sci. 2001 Oct;22(10):519-525.

Binding of Gto the calcium channel displaces the beta subunit of the calcium channel

Zamponi GW, Snutch TP. Modulation of voltage-dependent calcium channels by G proteins.Curr Opin Neurobiol. 1998 Jun;8(3):351-356.

Interaction of Gwith the calcium channel induces the “reluctant” state

Zamponi GW, Snutch TP. Modulation of voltage-dependent calcium channels by G proteins.Curr Opin Neurobiol. 1998 Jun;8(3):351-356.

Cross-talk beween Gand protein kinase C in the modulation of calcium current

Cooper CB, Arnot MI, Feng ZP, Jarvis SE, Hamid J, Zamponi GW. Cross-talk between G-protein and protein kinase C modulation of N-type calcium channels is dependent on the G-protein beta subunit isoform. J Biol Chem. 2000 Dec;275(52):40777-40781.

Cross-talk beween Gand protein kinase C in the modulation of calcium current is dependent on the type

of G

Cooper CB, Arnot MI, Feng ZP, Jarvis SE, Hamid J, Zamponi GW. Cross-talk between G-protein and protein kinase C modulation of N-type calcium channels is dependent on the G-protein beta subunit isoform. J Biol Chem. 2000 Dec;275(52):40777-40781.

Dual regulation of voltage-gated calcium channels by PtdIns (4,5)P2

Wu L, Bauer CS, Zhen XG, Xie C, Yang J. Nature. 2002 Oct;419(6910):947-952.

Stabilization of P/Q calcium current by PIP2

Tail current can be used to measure functional channels

PIP2 slowed down rundown after patch excision

Mg-ATP slowed down rundown after patch excision

Wu L, Bauer CS, Zhen XG, Xie C, Yang J. Dual regulation of voltage-gated calcium channels by PtdIns(4,5)P2.Nature. 2002 Oct;419(6910):947-952.

PtdIns (4,5)P2 induced voltage-dependent inhibition

Wu L, Bauer CS, Zhen XG, Xie C, Yang J. Dual regulation of voltage-gated calcium channels by PtdIns(4,5)P2.Nature. 2002 Oct;419(6910):947-952.

Receptor-mediated PIP2 hydrolysis: LHRH in frog sympathetic neurons

Inhibition is voltage-independent

Inhibition of PLC of U732122

Wu L, Bauer CS, Zhen XG, Xie C, Yang J. Dual regulation of voltage-gated calcium channels by PtdIns(4,5)P2.Nature. 2002 Oct;419(6910):947-952.

Multiple G protein coupled receptors mediate the inhibition of neuronal calcium channels

Strock J, Diverse-Pierluissi MA. Ca2+ channels as integrators of G protein-mediated signaling in neurons. Mol Pharmacol. 2004 Nov;66(5):1071-1076. Epub 2004 Jul 21.

Cav2.2 channel

synaptotagmin (v-SNARE)

SNAP-25v

syntaxin

Cav2.2 channel

SNAP-25

syntaxin X

v

“willing”

“reluctant”

Binding of SNARE proteins to neuronal calcium channels

Muth JN, Varadi G, Schwartz A. Use of transgenic mice to study voltage-dependent Ca2+ channels. Trends Pharmacol Sci. 2001 Oct;22(10):526-532.

Muth JN, Varadi G, Schwartz A. Use of transgenic mice to

study voltage-dependent Ca2+ channels.

Trends Pharmacol Sci. 2001 Oct;22(10):526-532.

Diverse-Pierluissi M, Remmers AE, Neubig RR, Dunlap K. Novel form of crosstalk between G protein and tyrosine kinase pathways. Proc Natl Acad Sci U S A. 1997 May 13;94(10):5417-21.

Time course of GABA-B receptor-mediated inhibition of N type current

PI3K promotes voltage dependent calcium channel trafficking in the

plasma membrane

Viard P, Butcher AJ, Halet G, Davies A, Nurnberg B, Heblich F, Dolphin AC. Nat Neurosci. 2004

Sep;7(9):939-946.

Effect of PI3K-induced production of PIP3 on Cav1.2/2a currents

Viard P, Butcher AJ, Halet G, Davies A, Nurnberg B, Heblich F, Dolphin AC. PI3K promotes voltage-dependent calcium channel trafficking to the plasma membrane. Nat Neurosci. 2004 Sep;7(9):939-946.

Effect of PI3K on Calcium Channel Membrane Localization

Viard P, Butcher AJ, Halet G, Davies A, Nurnberg B, Heblich F, Dolphin AC. PI3K promotes voltage-dependent calcium channel trafficking to the plasma membrane. Nat Neurosci. 2004 Sep;7(9):939-946.

Effect of S574A mutation on the PI3K and myr-Akt/PKB-induced regulation of Cav2.2

channels

Viard P, Butcher AJ, Halet G, Davies A, Nurnberg B, Heblich F, Dolphin AC. PI3K promotes voltage-dependent calcium channel trafficking to the plasma membrane. Nat Neurosci. 2004 Sep;7(9):939-946.