γ1-dependent down-regulation of recombinant voltage-gated Ca2+ channels

Alejandro Sandoval, Jyothi Arikkath, Eduardo Monjaraz, Kevin P. Campbell, Ricardo Felix

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

(1) Voltage-gated Ca2+ (CaV) channels are multi-subunit membrane complexes that allow depolarization-induced Ca 2+ influx into cells. The skeletal muscle L-type CaV channels consist of an ion-conducting CaV1.1 subunit and auxiliary α2δ-1, β1 and γ1 subunits. This complex serves both as a CaV channel and as a voltage sensor for excitation-contraction coupling. (2) Though much is known about the mechanisms by which the α2δ-1 and β1 subunits regulate CaV channel function, there is far less information on the γ1 subunit. Previously, we characterized the interaction of γ1 with the other components of the skeletal CaV channel complex, and showed that heterologous expression of this auxiliary subunit decreases Ca2+ current density in myotubes from γ1 null mice. (3) In the current report, using Western blotting we show that the expression of the CaV1.1 protein is significantly lower when it is heterologously co-expressed with γ1. Consistent with this, patch-clamp recordings showed that transient transfection of γ1 drastically inhibited macroscopic currents through recombinant N-type (CaV2.2/α2δ-1/ β3) channels expressed in HEK-293 cells. (4) These findings provide evidence that co-expression of the auxiliary γ1 subunit results in a decreased expression of the ion-conducting subunit, which may help to explain the reduction in Ca2+ current density following γ1 transfection.

Original languageEnglish (US)
Pages (from-to)901-908
Number of pages8
JournalCellular and molecular neurobiology
Volume27
Issue number7
DOIs
StatePublished - Nov 1 2007

Fingerprint

Transfection
Current density
Down-Regulation
Excitation Contraction Coupling
HEK293 Cells
Skeletal Muscle Fibers
Depolarization
Clamping devices
Electric potential
Ion Channels
Muscle
Skeletal Muscle
Western Blotting
Ions
Membranes
Sensors
Proteins

Keywords

  • Ca channels
  • HEK-293 cells
  • Patch-clamp
  • γ subunit

ASJC Scopus subject areas

  • Cellular and Molecular Neuroscience
  • Cell Biology

Cite this

γ1-dependent down-regulation of recombinant voltage-gated Ca2+ channels. / Sandoval, Alejandro; Arikkath, Jyothi; Monjaraz, Eduardo; Campbell, Kevin P.; Felix, Ricardo.

In: Cellular and molecular neurobiology, Vol. 27, No. 7, 01.11.2007, p. 901-908.

Research output: Contribution to journalArticle

Sandoval, Alejandro ; Arikkath, Jyothi ; Monjaraz, Eduardo ; Campbell, Kevin P. ; Felix, Ricardo. / γ1-dependent down-regulation of recombinant voltage-gated Ca2+ channels. In: Cellular and molecular neurobiology. 2007 ; Vol. 27, No. 7. pp. 901-908.
@article{187224c7370f45efb7f51fd04e44d150,
title = "γ1-dependent down-regulation of recombinant voltage-gated Ca2+ channels",
abstract = "(1) Voltage-gated Ca2+ (CaV) channels are multi-subunit membrane complexes that allow depolarization-induced Ca 2+ influx into cells. The skeletal muscle L-type CaV channels consist of an ion-conducting CaV1.1 subunit and auxiliary α2δ-1, β1 and γ1 subunits. This complex serves both as a CaV channel and as a voltage sensor for excitation-contraction coupling. (2) Though much is known about the mechanisms by which the α2δ-1 and β1 subunits regulate CaV channel function, there is far less information on the γ1 subunit. Previously, we characterized the interaction of γ1 with the other components of the skeletal CaV channel complex, and showed that heterologous expression of this auxiliary subunit decreases Ca2+ current density in myotubes from γ1 null mice. (3) In the current report, using Western blotting we show that the expression of the CaV1.1 protein is significantly lower when it is heterologously co-expressed with γ1. Consistent with this, patch-clamp recordings showed that transient transfection of γ1 drastically inhibited macroscopic currents through recombinant N-type (CaV2.2/α2δ-1/ β3) channels expressed in HEK-293 cells. (4) These findings provide evidence that co-expression of the auxiliary γ1 subunit results in a decreased expression of the ion-conducting subunit, which may help to explain the reduction in Ca2+ current density following γ1 transfection.",
keywords = "Ca channels, HEK-293 cells, Patch-clamp, γ subunit",
author = "Alejandro Sandoval and Jyothi Arikkath and Eduardo Monjaraz and Campbell, {Kevin P.} and Ricardo Felix",
year = "2007",
month = "11",
day = "1",
doi = "10.1007/s10571-007-9210-9",
language = "English (US)",
volume = "27",
pages = "901--908",
journal = "Cellular and Molecular Neurobiology",
issn = "0272-4340",
publisher = "Springer New York",
number = "7",

}

TY - JOUR

T1 - γ1-dependent down-regulation of recombinant voltage-gated Ca2+ channels

AU - Sandoval, Alejandro

AU - Arikkath, Jyothi

AU - Monjaraz, Eduardo

AU - Campbell, Kevin P.

AU - Felix, Ricardo

PY - 2007/11/1

Y1 - 2007/11/1

N2 - (1) Voltage-gated Ca2+ (CaV) channels are multi-subunit membrane complexes that allow depolarization-induced Ca 2+ influx into cells. The skeletal muscle L-type CaV channels consist of an ion-conducting CaV1.1 subunit and auxiliary α2δ-1, β1 and γ1 subunits. This complex serves both as a CaV channel and as a voltage sensor for excitation-contraction coupling. (2) Though much is known about the mechanisms by which the α2δ-1 and β1 subunits regulate CaV channel function, there is far less information on the γ1 subunit. Previously, we characterized the interaction of γ1 with the other components of the skeletal CaV channel complex, and showed that heterologous expression of this auxiliary subunit decreases Ca2+ current density in myotubes from γ1 null mice. (3) In the current report, using Western blotting we show that the expression of the CaV1.1 protein is significantly lower when it is heterologously co-expressed with γ1. Consistent with this, patch-clamp recordings showed that transient transfection of γ1 drastically inhibited macroscopic currents through recombinant N-type (CaV2.2/α2δ-1/ β3) channels expressed in HEK-293 cells. (4) These findings provide evidence that co-expression of the auxiliary γ1 subunit results in a decreased expression of the ion-conducting subunit, which may help to explain the reduction in Ca2+ current density following γ1 transfection.

AB - (1) Voltage-gated Ca2+ (CaV) channels are multi-subunit membrane complexes that allow depolarization-induced Ca 2+ influx into cells. The skeletal muscle L-type CaV channels consist of an ion-conducting CaV1.1 subunit and auxiliary α2δ-1, β1 and γ1 subunits. This complex serves both as a CaV channel and as a voltage sensor for excitation-contraction coupling. (2) Though much is known about the mechanisms by which the α2δ-1 and β1 subunits regulate CaV channel function, there is far less information on the γ1 subunit. Previously, we characterized the interaction of γ1 with the other components of the skeletal CaV channel complex, and showed that heterologous expression of this auxiliary subunit decreases Ca2+ current density in myotubes from γ1 null mice. (3) In the current report, using Western blotting we show that the expression of the CaV1.1 protein is significantly lower when it is heterologously co-expressed with γ1. Consistent with this, patch-clamp recordings showed that transient transfection of γ1 drastically inhibited macroscopic currents through recombinant N-type (CaV2.2/α2δ-1/ β3) channels expressed in HEK-293 cells. (4) These findings provide evidence that co-expression of the auxiliary γ1 subunit results in a decreased expression of the ion-conducting subunit, which may help to explain the reduction in Ca2+ current density following γ1 transfection.

KW - Ca channels

KW - HEK-293 cells

KW - Patch-clamp

KW - γ subunit

UR - http://www.scopus.com/inward/record.url?scp=37549058407&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=37549058407&partnerID=8YFLogxK

U2 - 10.1007/s10571-007-9210-9

DO - 10.1007/s10571-007-9210-9

M3 - Article

C2 - 17934806

AN - SCOPUS:37549058407

VL - 27

SP - 901

EP - 908

JO - Cellular and Molecular Neurobiology

JF - Cellular and Molecular Neurobiology

SN - 0272-4340

IS - 7

ER -