Related Experiment Video
Updated: Jul 25, 2026
12:10
Measuring Fast Calcium Fluxes in Cardiomyocytes
Published on: November 29, 2011
Reversibility of the Ca(2+) channel alpha(1)-beta subunit interaction
D Bichet1, C Lecomte, J M Sabatier
1Laboratoire de Neurobiologie des Canaux Ioniques, Laboratoire de Biochimie, CNRS UMR 6560, INSERM U464, Institut Fédératif Jean Roche, Boulevard Pierre Dramard, Marseille Cedex 20, 13916, France.
Biochemical and Biophysical Research Communications
|November 4, 2000
Summary
Synthetic peptides targeting the alpha(1)-beta interaction in voltage-dependent Ca(2+) channels show reversible disruption. This suggests a novel mechanism for Ca(2+) channel regulation and highlights multiple interaction sites between subunits.
Area of Science:
- Molecular and Cellular Neuroscience
- Ion Channel Physiology
- Protein-Protein Interactions
Background:
- Auxiliary beta subunits are critical regulators of voltage-dependent Ca(2+) channel activity.
- The interaction between beta subunits and the alpha(1) subunit's AID domain is key to this regulation.
- Understanding this interaction is crucial for deciphering Ca(2+) channel function.
Purpose of the Study:
- To investigate the role of the alpha(1)-beta subunit interaction in Ca(2+) channel regulation.
- To explore the potential for disrupting this interaction using synthetic peptides.
- To examine the reversibility of channel subunit association.
Main Methods:
- Utilized two synthetic peptides derived from the alpha(1A) subunit's I-II linker (AID(A)-peptides).
- Performed in vitro binding experiments to assess peptide affinity for the beta(3) subunit.
- Conducted immunoprecipitation assays using anti-beta(3) antibodies on native N- and P/Q-type channels.
Main Results:
- AID(A)-peptides demonstrated reasonable in vitro affinity for the neuronal beta(3) subunit.
- These peptides did not prevent the immunoprecipitation of native N- and P/Q-type channels by anti-beta(3) antibodies.
- Results suggest the alpha(1)-beta interaction is reversible and involves multiple binding sites.
Conclusions:
- Disruption of the alpha(1)-beta interaction may represent a physiological mechanism for Ca(2+) channel regulation.
- The findings support a model where alpha(1)-beta subunit association is mediated by multiple interaction sites.
- This study provides evidence for the dynamic nature of ion channel subunit assembly.
More Related Videos
Related Concept Videos
01:21G-Protein Gated Ion Channels
GPCRs are primarily responsible for our sense of smell, taste, and vision. The binding of a sensory stimulus activates GPCR to stimulate effector proteins, many of which are ion channels in the sensory organs. GPCRs modulate the opening and closing of the target ion channels either directly by binding them, or by releasing second messengers that activate these channels. As ions move across the membrane, the membrane potential is altered, which induces an appropriate response.
Sensory organs,...
Sensory organs,...
01:16Calmodulin-dependent Signaling
Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
01:30Ligand-Gated Ion Channel Receptor: Gating Mechanism
Ligand-gated ion channels are transmembrane proteins that play a vital role in intercellular communication and functions of the nervous system. They allow the influx of ions across the membrane once the neurotransmitter binds, allowing the subsequent transmission of electrical excitation across the neurons. Other ligand-gated ion channels, like the γ-aminobutyric acid (GABA) receptor, permit anions like chloride into the cells on the binding of the GABA molecule. Their entry into the cell...
01:20Desensitization and Tachyphylaxis
Tachyphylaxis is described as a rapid decrease in response to a drug after repeated or continuous administration of the same drug dose. It is a phenomenon where the body becomes less responsive to a particular substance or intervention over time, requiring higher doses or stronger interventions to achieve the same effect. It results from adaptive changes in the body's receptors, signaling pathways, or physiological processes that occur in response to prolonged exposure to a stimulus.
Several...
Several...
01:26Adrenergic Receptors: β Subtype
β-adrenoceptors have varied sensitivities towards adrenaline, noradrenaline, and isoprenaline. The order of agonist potency is as follows:
Isoprenaline > Adrenaline > Noradrenaline
Neurotransmitter binding to these receptors causes activation of adenylyl cyclase resulting in increased concentrations of cAMP and modulation of calcium ion channels within the cell. They are further classified into β1, β2, and β3 subtypes.
β1-adrenoceptors: β1-adrenoceptors have equal affinities for...
Isoprenaline > Adrenaline > Noradrenaline
Neurotransmitter binding to these receptors causes activation of adenylyl cyclase resulting in increased concentrations of cAMP and modulation of calcium ion channels within the cell. They are further classified into β1, β2, and β3 subtypes.
β1-adrenoceptors: β1-adrenoceptors have equal affinities for...
01:18Antihypertensive Drugs: Action of Calcium Channel Blockers
Calcium ions are essential to contract smooth muscle cells in blood vessels. They enter these cells through voltage-dependent calcium channels, specifically L-type calcium channels in the cell membrane. These L-type calcium channels are integral to the excitation-contraction coupling process in smooth muscle. When a stimulus is received by smooth muscle cells, their membrane depolarizes. This alteration in membrane potential instigates the opening of L-type calcium channels. As a result,...