KCNE2 Protein

KCNE2 Protein

Overview

<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">KCNE2 Protein</th>
</tr>
<tr>
<td class="label">Protein Name</td>
<td>Potassium voltage-gated channel subfamily E member 2</td>
</tr>
<tr>
<td class="label">Gene</td>
<td>[KCNE2](/genes/kcne2)</td>
</tr>
<tr>
<td class="label">UniProt ID</td>
<td>[P31645](https://www.uniprot.org/uniprot/P31645)</td>
</tr>
<tr>
<td class="label">PDB ID</td>
<td>2KPL</td>
</tr>
<tr>
<td class="label">Molecular Weight</td>
<td>14.7 kDa</td>
</tr>
<tr>
<td class="label">Subcellular Localization</td>
<td>Plasma membrane</td>
</tr>
<tr>
<td class="label">Protein Family</td>
<td>KCNE family (MinK-like)</td>
</tr>
<tr>
<td class="label">Tissue Expression</td>
<td>Heart, Brain ([cortex](/brain-regions/cortex), hippocampus), Skeletal muscle, Stomach</td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">1 edges</a></td>
</tr>
</table>

KCNE2 (Potassium voltage-gated channel subfamily E member 2, also known as MinK-Related Peptide 1 or MiRP1) is a regulatory subunit of multiple potassium channels that plays essential roles in cardiac repolarization and neuronal excitability. This protein is implicated in neurodegenerative diseases through its modulatory effects on potassium channel function.

Introduction

KCNE2 Protein

Overview

<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">KCNE2 Protein</th>
</tr>
<tr>
<td class="label">Protein Name</td>
<td>Potassium voltage-gated channel subfamily E member 2</td>
</tr>
<tr>
<td class="label">Gene</td>
<td>[KCNE2](/genes/kcne2)</td>
</tr>
<tr>
<td class="label">UniProt ID</td>
<td>[P31645](https://www.uniprot.org/uniprot/P31645)</td>
</tr>
<tr>
<td class="label">PDB ID</td>
<td>2KPL</td>
</tr>
<tr>
<td class="label">Molecular Weight</td>
<td>14.7 kDa</td>
</tr>
<tr>
<td class="label">Subcellular Localization</td>
<td>Plasma membrane</td>
</tr>
<tr>
<td class="label">Protein Family</td>
<td>KCNE family (MinK-like)</td>
</tr>
<tr>
<td class="label">Tissue Expression</td>
<td>Heart, Brain ([cortex](/brain-regions/cortex), hippocampus), Skeletal muscle, Stomach</td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">1 edges</a></td>
</tr>
</table>

KCNE2 (Potassium voltage-gated channel subfamily E member 2, also known as MinK-Related Peptide 1 or MiRP1) is a regulatory subunit of multiple potassium channels that plays essential roles in cardiac repolarization and neuronal excitability. This protein is implicated in neurodegenerative diseases through its modulatory effects on potassium channel function.

Introduction

KCNE2 is a member of the KCNE family of single transmembrane domain proteins that function as auxiliary subunits of voltage-gated potassium channels. Unlike the Kv beta subunits, KCNE proteins have a distinct structure with a single transmembrane helix and extracellular N-terminus[@channel].

KCNE2 is uniquely versatile among KCNE family members because it can associate with multiple different potassium channel alpha subunits, including KCNQ1 (Kv7.1), hERG (KCNH2), and various Kv channels. This broad interaction profile makes KCNE2 particularly important for cellular excitability in multiple tissues.

Protein Overview

Structure

KCNE2 is a type I membrane protein with a distinctive architecture:

• N-terminal Domain: Extracellular domain involved in subunit interactions
• Transmembrane Domain: Single α-helix that anchors the protein in the membrane
• C-terminal Domain: Cytoplasmic domain that mediates interactions with channel alpha subunits

Normal Function

Channel Modulation

KCNE2 modulates potassium channels through several mechanisms:

Physiological Roles

• Cardiac Repolarization: KCNE2 with KCNQ1 forms the I(Ks) current, critical for cardiac action potential repolarization
• Neuronal Excitability: Modulates neuronal potassium currents affecting action potential shape
• Gastrointestinal Function: Regulates gastric epithelial potassium channels
• Metabolic Regulation: Involved in insulin secretion from pancreatic β-cells

Role in Neurodegenerative Diseases

Alzheimer's Disease

KCNE2 is implicated in Alzheimer's disease through[@potassium]:

• Neuronal Hyperexcitability: [Aβ](/proteins/amyloid-beta) peptides disrupt KCNE2-mediated potassium currents, leading to increased neuronal excitability
• Calcium Dysregulation: Altered potassium channel function affects calcium homeostasis
• Synaptic Dysfunction: Impaired synaptic integration and plasticity
• Metabolic Stress: Dysregulated neuronal energy metabolism

Parkinson's Disease

In Parkinson's disease, KCNE2 affects:

• Dopaminergic Neuron Function: Regulates excitability of substantia nigra pars compacta [neurons](/entities/neurons)
• Oxidative Stress Response: Potassium channel dysfunction can exacerbate oxidative damage
• Mitochondrial Function: Links between ion channel activity and mitochondrial health

Epilepsy

KCNE2 mutations have been associated with epilepsy susceptibility, reflecting its critical role in neuronal excitability control[@therapeutic].

Heart-Brain Connection

Given its dual role in cardiac and neuronal excitability, KCNE2 may provide a mechanistic link between cardiovascular dysfunction and neurodegenerative diseases.

Therapeutic Implications

Current Approaches

Research Directions

• Precision Medicine: KCNE2 polymorphisms may influence drug responses
• Combination Therapies: Targeting multiple KCNE-modulated channels
• Disease Biomarkers: KCNE2 expression as a biomarker for neurodegeneration

Interactions

KCNE2 interacts with multiple potassium channel alpha subunits:

• KCNQ1 (Kv7.1): Forms the I(Ks) cardiac current
• KCNH2 (hERG): Forms the I(Kr) cardiac current
• KCNQ2/KCNQ3: Neuronal M-currents
• Kv1.5: Vascular smooth muscle currents

Research Background

Key milestones in KCNE2 research:

• 1998: Discovery of KCNE gene family
• 2001: Link to cardiac arrhythmias established
• 2005: Structure determination (PDB: 2KPL)
• 2010s: Neurological implications explored

Background

The study of Kcne2 Protein 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

• KCNE2 Gene
• [Ion Channel Dysfunction](/mechanisms/ion-channel-dysfunction)
• [Alzheimer's Disease](/diseases/alzheimers-disease)
• [Parkinson's Disease](/diseases/parkinsons-disease)
• Voltage-Gated Potassium Channels
• KCNQ1 Channel
• [Neuronal Excitability](/mechanisms/neuronal-hyperexcitability)

External Links

• [UniProt: P31645](https://www.uniprot.org/uniprot/P31645)
• [PDB: 2KPL](https://www.rcsb.org/)
• [GeneCards: KCNE2](https://www.genecards.org/cgi-bin/carddisp.pl?gene=KCNE2)

References