CACNB2 Protein (CaB2)

CACNB2 Protein (CaB2)

<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">CACNB2 Protein (CaB2)</th>
</tr>
<tr>
<td class="label">Protein Name</td>
<td>CACNB2 (Calcium Channel Voltage-Dependent Beta 2 Subunit)</td>
</tr>
<tr>
<td class="label">Gene</td>
<td>CACNB2</td>
</tr>
<tr>
<td class="label">UniProt ID</td>
<td>Q99986</td>
</tr>
<tr>
<td class="label">Molecular Mass</td>
<td>56.7 kDa</td>
</tr>
<tr>
<td class="label">Protein Class</td>
<td>Voltage-Gated Calcium Channel Beta Subunit</td>
</tr>
<tr>
<td class="label">Tissue Specificity</td>
<td>Heart, brain, adrenal gland, lung</td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">1 edges</a></td>
</tr>
</table>

Introduction

Cacnb2 Protein (Cab2) is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.

Overview

Protein Structure

CACNB2 is the beta2 (β2) auxiliary subunit of voltage-gated calcium channels (VGCCs). It belongs to the MAGUK (Membrane-Associated Guanylate Kinase) protein family and contains conserved domains for interaction with the α1 subunit[@aime2019].

Domain Architecture

...

CACNB2 Protein (CaB2)

<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">CACNB2 Protein (CaB2)</th>
</tr>
<tr>
<td class="label">Protein Name</td>
<td>CACNB2 (Calcium Channel Voltage-Dependent Beta 2 Subunit)</td>
</tr>
<tr>
<td class="label">Gene</td>
<td>CACNB2</td>
</tr>
<tr>
<td class="label">UniProt ID</td>
<td>Q99986</td>
</tr>
<tr>
<td class="label">Molecular Mass</td>
<td>56.7 kDa</td>
</tr>
<tr>
<td class="label">Protein Class</td>
<td>Voltage-Gated Calcium Channel Beta Subunit</td>
</tr>
<tr>
<td class="label">Tissue Specificity</td>
<td>Heart, brain, adrenal gland, lung</td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">1 edges</a></td>
</tr>
</table>

Introduction

Cacnb2 Protein (Cab2) is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.

Overview

Protein Structure

CACNB2 is the beta2 (β2) auxiliary subunit of voltage-gated calcium channels (VGCCs). It belongs to the MAGUK (Membrane-Associated Guanylate Kinase) protein family and contains conserved domains for interaction with the α1 subunit[@aime2019].

Domain Architecture

• SH3 Domain: For protein-protein interactions
• Kinase-like Domain: Core β subunit structure (belongs to the SHAGGY family of kinases)
• AID Region: High-affinity binding site for α1 subunit
• PDZ-binding Motif: Postsynaptic density interactions

Molecular Function

CACNB2 modulates calcium channel function through multiple mechanisms[@ebersole2000]:

Trafficking Enhancement: Promotes correct localization of VGCCs to the plasma membrane

Gating Modulation: Alters voltage-dependence and kinetics of channel opening

Channel Stabilization: Prevents degradation of the α1 subunit

Synaptic Targeting: Guides channels to synaptic locations

Beta-adrenergic Modulation: Mediates catecholamine effects on calcium channels

Expression in the Brain

CACNB2 is expressed throughout the brain with particularly high levels in[@mcenery2004]:

• [Hippocampus](/brain-regions/hippocampus) (CA1-CA3 regions)
• Cerebral [cortex](/brain-regions/cortex) (layer 2/3 pyramidal neurons)
• Cerebellum (Purkinje cells)
• Thalamus
• Basal ganglia

The β2 subunit is critical for proper synaptic function and plasticity.

Role in Neurodegeneration

Alzheimer's Disease

CACNB2 plays important roles in AD pathogenesis[@nikolov2012]:

• Calcium Dysregulation: Altered β2 subunit function contributes to disturbed calcium homeostasis
• Synaptic Dysfunction: Impaired VGCC trafficking affects synaptic transmission
• [Aβ](/proteins/amyloid-beta) Effects: Amyloid-beta modulates β2-containing channel function
• [Tau](/proteins/tau) Pathology: Hyperphosphorylated [tau](/proteins/tau) affects channel localization

Parkinson's Disease

• Motor Circuit Dysfunction: Altered calcium signaling in dopaminergic [neurons](/entities/neurons)
• Oxidative Stress: Calcium-dependent [ROS](/entities/reactive-oxygen-species) production enhanced by VGCC dysfunction
• Neuroprotection: β2-containing channels may be targets for neuroprotective therapy

Epilepsy

CACNB2 mutations cause epilepsy syndromes in humans and mice[@escayg2000]. The β2 subunit is essential for proper excitatory/inhibitory balance.

Autism Spectrum Disorders

Genetic variants in CACNB2 have been associated with ASD[@fatemi2018], reflecting its critical role in synaptic function.

Stroke and Vascular Dementia

β2-containing channels in cerebral vasculature affect blood flow regulation[@baur2016].

Therapeutic Implications

Channel Modulators

Drugs targeting β2-containing VGCCs[@zamponi2015]:

• FDA-approved: Gabapentin, pregabalin (α2δ ligands that affect trafficking)
• In Development: Selective β2 subunit modulators

Genetic Approaches

• Gene Therapy: AAV-CACNB2 for restoring channel function
• ASO Therapy: Antisense oligonucleotides targeting pathogenic variants

Repurposing Opportunities

Existing cardiovascular drugs affecting VGCCs may have CNS applications.

Research Tools

• Antibodies: Anti-CACNB2 (Abcam, Alomone Labs)
• Transgenic Mice: CACNB2 knockout and conditional knockout lines
• Cell Lines: HEK293, neurons expressing specific β2 splice variants

Background

The study of Cacnb2 Protein (Cab2) has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.

Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.

See Also

• CACNB2 Gene
• Voltage-Gated Calcium Channels
• [Calcium Signaling in Neurodegeneration](/mechanisms/calcium-signaling-neurodegeneration) [Alzheimer's Disease](/diseases/alzheimers-disease)
• [Parkinson's Disease](/diseases/parkinsons-disease)
• [Epilepsy](/diseases/epilepsy)
• [Synaptic Dysfunction](/mechanisms/synaptic-dysfunction)