Kcnh2 — Potassium Voltage Gated Channel Subfamily H Member 2 is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
<div class="infobox infobogene"> [@smad]
| Field | Value | [@transcriptional]
|-------|-------| [@neuroinflammation]
| Gene Symbol | KCNH2 | [@astrocyte]
| Full Name | Potassium Voltage-Gated Channel Subfamily H Member 2 |
| Chromosomal Location | 7q36.1 |
| NCBI Gene ID | 3759 |
| OMIM ID | 607446 |
| Ensembl ID | ENSG00000196878 |
| UniProt ID | Q14721 |
| Associated Diseases | Long QT Syndrome, Short QT Syndrome, Torsades de Pointes, Sudden Cardiac Death, Alzheimer's Disease, Parkinson's Disease |
</div>
Kcnh2 — Potassium Voltage Gated Channel Subfamily H Member 2 is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
<div class="infobox infobogene"> [@smad]
| Field | Value | [@transcriptional]
|-------|-------| [@neuroinflammation]
| Gene Symbol | KCNH2 | [@astrocyte]
| Full Name | Potassium Voltage-Gated Channel Subfamily H Member 2 |
| Chromosomal Location | 7q36.1 |
| NCBI Gene ID | 3759 |
| OMIM ID | 607446 |
| Ensembl ID | ENSG00000196878 |
| UniProt ID | Q14721 |
| Associated Diseases | Long QT Syndrome, Short QT Syndrome, Torsades de Pointes, Sudden Cardiac Death, Alzheimer's Disease, Parkinson's Disease |
</div>
KCNH2 (also known as HERG1, Kv11.1, or LQT2) encodes the potassium voltage-gated channel subfamily H member 2, a crucial ion channel protein that forms the rapid component of the delayed rectifier potassium current (I_Kr) in cardiac myocytes and [neurons](/entities/neurons). This channel is essential for cardiac repolarization and neuronal excitability, with growing evidence linking dysfunction to neurodegenerative diseases.
The KCNH2 channel is a voltage-gated potassium channel composed of four α-subunits, each containing six transmembrane segments (S1-S6). The S4 segment serves as the voltage sensor, while the S5-S6 pore region forms the ion conduction pathway. The channel undergoes characteristic voltage-dependent activation and inactivation, with slow deactivation kinetics that are critical for its physiological function.
In the heart, KCNH2 conducts the I_Kr current, which is essential for phase 3 repolarization of the cardiac action potential. Loss-of-function mutations cause Long QT Syndrome type 2 (LQT2), while gain-of-function mutations cause Short QT Syndrome.
In the brain, KCNH2 is expressed in various regions including the hippocampus, cortex, thalamus, and basal ganglia. Neuronal KCNH2 channels contribute to:
| Condition | Mutation Type | Mechanism |
|-----------|--------------|-----------|
| Long QT Syndrome Type 2 | Loss-of-function | Reduced I_Kr current prolongs QT interval |
| Short QT Syndrome Type 1 | Gain-of-function | Increased I_Kr current shortens QT interval |
| Torsades de Pointes | Dysfunction | Triggered by prolonged QT |
| Sudden Cardiac Death | Loss-of-function | Fatal cardiac arrhythmias |
| Region | Expression Level | Functional Significance |
|--------|----------------|----------------------|
| [Hippocampus](/brain-regions/hippocampus) | High | Synaptic plasticity, learning |
| Cerebral [Cortex](/brain-regions/cortex) | High | Cortical processing |
| Basal Ganglia | Moderate | Motor control |
| Thalamus | Moderate | Sensory integration |
| Cerebellum | Moderate | Motor coordination |
KCNH2 is expressed in both excitatory pyramidal neurons and inhibitory interneurons, with particularly high expression in GABAergic neurons where it contributes to inhibitory signaling.
| Compound | Mechanism | Development Status | Indication |
|----------|-----------|-------------------|------------|
| E-4031 | HERG blocker | Research | Antiarrhythmic |
| Dofetilide | HERG blocker | FDA approved | Atrial fibrillation |
| Dronedarone | HERG blocker | FDA approved | Arrhythmia |
| Almokalant | HERG blocker | Research | Antiarrhythmic |
The study of Kcnh2 — Potassium Voltage Gated Channel Subfamily H Member 2 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.
The following diagram shows the key molecular relationships involving KCNH2 — Potassium Voltage-Gated Channel Subfamily H Member 2 discovered through SciDEX knowledge graph analysis: