GO:0086005 ventricular cardiac muscle cell action potential: Electrophysiology, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0086005 describes the action potential that occurs specifically in ventricular cardiac muscle cells, the electrical signal that triggers each heartbeat.
• The ventricular action potential is shaped by a precise sequence of ion channel currents, including INa, ICaL, Ito, IKr, IKs, and IK1, which together determine its long plateau and repolarization phase.
• Disruption of these currents, for example by microRNA-365 or gefitinib, can prolong action potential duration and QT interval, increasing arrhythmia risk.
• Intracellular ATP dynamics are tightly coupled to excitation-contraction coupling in ventricular myocytes, linking metabolism to electrical stability.
• Action potential duration adapts to stimulation frequency and beta-adrenergic stimulation, a property critical for cardiac reserve.
• Experimental models range from primary ventricular myocytes and micropatterned cultures to in silico simulations and CRISPR-engineered cell lines.
Description
The ventricular cardiac muscle cell action potential (GO:0086005) is the electrical impulse that sweeps across the membrane of a ventricular myocyte, initiating contraction and coordinating the heartbeat. It is a specialized biological process distinct from action potentials in neurons or atrial cells, characterized by a long plateau phase that allows calcium entry and efficient muscle contraction. Understanding this process is fundamental to cardiac electrophysiology, as even subtle changes in its duration or shape can predispose to life-threatening arrhythmias. Researchers study GO:0086005 to dissect the contributions of individual ion channels, to model drug effects, and to develop therapies for inherited and acquired cardiac disorders. The term encompasses the entire time course from rapid depolarization to full repolarization, integrating membrane currents, intracellular signaling, and metabolic state.
ventricular cardiac muscle cell action potential At A Glance
| GO ID | GO:0086005 |
|---|---|
| GO term | ventricular cardiac muscle cell action potential |
| Ontology | biological_process |
| Synonym | none |
| Major function | Electrical excitation of ventricular myocytes that triggers contraction |
| Key ion currents | INa, ICaL, Ito, IKr, IKs, IK1 |
| Cell type | Ventricular cardiac muscle cell (cardiomyocyte) |
| Related process | Excitation-contraction coupling |
| Disease relevance | Arrhythmias, QT prolongation, heart failure |
What Is GO:0086005?
According to the Gene Ontology, GO:0086005 is defined as an action potential that occurs in a ventricular cardiac muscle cell. In other words, it is the self-regenerating electrical wave that ventricular myocytes generate to trigger contraction, encompassing the coordinated opening and closing of ion channels that produce the characteristic phases of depolarization, plateau, and repolarization.
Why Is ventricular cardiac muscle cell action potential Important in Cell Biology?
GO:0086005 is essential because the ventricular action potential is the final common pathway for cardiac electrical activity, and its dysregulation directly causes arrhythmias and sudden cardiac death. The long plateau phase uniquely allows calcium influx that couples excitation to contraction, and its duration is finely tuned by multiple ion currents and signaling molecules. Studying this process helps researchers understand how genetic mutations, drugs, and metabolic stress alter cardiac excitability, and it provides a functional readout for testing new therapeutics.
• Defines the electrical signal that triggers each ventricular contraction.
• Its duration (QT interval) is a key biomarker for drug-induced arrhythmia risk.
• Mutations in ion channel genes that alter the action potential cause inherited arrhythmia syndromes.
• MicroRNAs such as miR-365 regulate action potential duration, linking gene regulation to electrophysiology.
• Metabolic state, including intracellular ATP, modulates action potential and contraction.
• Frequency-dependent adaptation (restitution) is critical for normal cardiac function.
• In silico models of the ventricular action potential aid drug safety testing.
• Micropatterned cardiac cultures with realistic ventricular microstructure improve physiological relevance.
• Cell-to-cell coupling in ventricular pairs influences action potential propagation.
• Provides a target for antiarrhythmic drug development and gene therapy.
What Happens During ventricular cardiac muscle cell action potential?
Phase 0: Rapid Depolarization
In simple terms: The cell rapidly becomes positive inside due to sodium rushing in.
In ventricular myocytes, phase 0 is driven by a massive influx of sodium ions through voltage-gated sodium channels, causing the membrane potential to rise quickly from about -90 mV to +20 mV. This rapid upstroke is essential for triggering the subsequent plateau and ensures synchronous contraction of the ventricular wall.
Phase 1: Early Repolarization
In simple terms: A brief partial recovery as some potassium leaves and sodium channels close.
Following the peak, transient outward potassium current (Ito) and inactivation of sodium channels cause a small dip in membrane potential, known as phase 1. This early repolarization sets the stage for the plateau and influences the overall action potential shape.
Phase 2: Plateau
In simple terms: A long pause where calcium enters and potassium leaves, keeping the cell depolarized.
The plateau phase is maintained by a balance between inward L-type calcium current (ICaL) and outward potassium currents, particularly IKr and IKs. This prolonged depolarization allows calcium to enter the cell and trigger calcium release from the sarcoplasmic reticulum, initiating contraction. The plateau is a hallmark of ventricular action potentials and distinguishes them from neuronal action potentials.
Phase 3: Repolarization
In simple terms: Potassium flows out, returning the cell to its resting negative state.
Repolarization is driven by the continued activation of IKs and IKr, along with the inward rectifier current IK1, which together restore the resting membrane potential. Restricting excessive action potential prolongation is vital, and IKs plays a key role in this repolarization reserve, especially at high heart rates.
Phase 4: Resting Potential
In simple terms: The cell rests at a negative voltage until the next heartbeat.
During diastole, the membrane potential is stabilized near -90 mV primarily by IK1. This resting state is critical for maintaining excitability and ensuring that the next action potential can be triggered by a new stimulus. Intracellular ATP levels also influence this phase by modulating ion channel activity and pump function.
Key Genes Involved in GO:0086005 ventricular cardiac muscle cell action potential
The ventricular cardiac muscle cell action potential depends on a diverse set of ion channel and regulatory genes; the table below lists key examples with their roles and research relevance.
| Gene | Major Role | Research Relevance |
|---|---|---|
| SCN5A | Voltage-gated sodium channel alpha subunit (INa) | Mutations cause Brugada syndrome and long QT syndrome |
| CACNA1C | L-type calcium channel alpha subunit (ICaL) | Target for calcium channel blockers; mutations cause Timothy syndrome |
| KCNH2 | hERG potassium channel (IKr) | Drug-induced QT prolongation; mutations cause LQT2 |
| KCNQ1 | Potassium channel alpha subunit (IKs) | Mutations cause LQT1; important for repolarization reserve |
| KCNJ2 | Inward rectifier potassium channel (IK1) | Mutations cause Andersen-Tawil syndrome |
| KCND3 | Transient outward potassium channel (Ito) | Modulates early repolarization; linked to Brugada syndrome |
| MIR365 | MicroRNA regulating action potential duration | miR-365 overexpression prolongs APD; potential therapeutic target |
| ATP1A1 | Na+/K+-ATPase alpha subunit | Maintains ionic gradients; energy dependent |
| ATP2A2 | SERCA2 calcium pump | Regulates calcium reuptake and relaxation |
| RYR2 | Ryanodine receptor calcium release channel | Mutations cause catecholaminergic polymorphic ventricular tachycardia |
| CACNB2 | Calcium channel beta subunit | Modulates ICaL; mutations linked to Brugada syndrome |
| SCN1B | Sodium channel beta subunit | Modulates INa; mutations cause cardiac arrhythmia |
| KCNE1 | Potassium channel beta subunit (minK) | Modulates IKs; mutations cause LQT5 |
| KCNE2 | Potassium channel beta subunit (MiRP1) | Modulates IKr; mutations cause LQT6 |
| GJA1 | Connexin 43 gap junction protein | Essential for cell-to-cell coupling in ventricular pairs |
| NPPA | Atrial natriuretic peptide | Marker of ventricular stress; not directly electrical |
| MYH7 | Beta-myosin heavy chain | Contraction; mutations cause hypertrophic cardiomyopathy |
| TNNT2 | Cardiac troponin T | Contraction regulation; mutations cause cardiomyopathy |
How Is ventricular cardiac muscle cell action potential Regulated?
The ventricular action potential is dynamically regulated by multiple mechanisms. Beta-adrenergic stimulation via isoproterenol increases heart rate and modulates ion currents, shortening action potential duration at high frequencies. MicroRNAs such as miR-365 can directly regulate action potential duration by targeting ion channel transcripts. Intracellular ATP levels fluctuate during excitation-contraction coupling and influence ATP-sensitive potassium channels and pumps, thereby affecting the action potential. Additionally, cell-to-cell coupling through gap junctions modulates propagation and repolarization in ventricular tissue.
ventricular cardiac muscle cell action potential and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| KCNH2 | Long QT syndrome type 2; drug-induced arrhythmia | CRISPR knockout in hiPSC-derived cardiomyocytes |
| MIR365 | Arrhythmia via action potential prolongation | Overexpression in human cardiac cells |
| SCN5A | Brugada syndrome; conduction disease | Point mutation knock-in in hiPSC-CMs |
| ATP2A2 | Heart failure; impaired calcium handling | Knockout in ventricular myocytes |
| GJA1 | Arrhythmia due to gap junction remodeling | Conditional knockout in mouse heart |
Long QT Syndrome and Drug-Induced Arrhythmia
Prolongation of the ventricular action potential, reflected as a prolonged QT interval on the ECG, increases the risk of torsades de pointes and sudden cardiac death. Drugs such as gefitinib can inhibit IKr and prolong the action potential, highlighting the need for careful electrophysiological screening. Restricting excessive action potential prolongation by enhancing IKs is a potential therapeutic strategy.
MicroRNA Dysregulation and Arrhythmia
MicroRNA-365 regulates human cardiac action potential duration, and its dysregulation can lead to arrhythmogenic changes in ion channel expression. This provides a novel layer of post-transcriptional control over cardiac excitability and a potential target for antiarrhythmic therapy.
Metabolic Stress and Heart Failure
In heart failure, altered intracellular ATP dynamics and metabolic remodeling impair excitation-contraction coupling and can destabilize the action potential. Understanding how ATP availability affects ion channels may reveal new therapeutic targets.
From ventricular cardiac muscle cell action potential-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does a candidate gene regulate action potential duration? | CRISPR knockout in hiPSC-derived ventricular cardiomyocytes |
| Does a specific point mutation alter ion channel gating? | Point mutation knock-in in HEK293 or hiPSC-CMs |
| Can a disease-associated variant be corrected? | Knock-in of wild-type allele via CRISPR |
| Where is a channel protein localized during the action potential? | Tagged knock-in with fluorescent protein |
| Does overexpression of a microRNA mimic arrhythmia? | Overexpression of miR-365 in cardiac cells |
| How do cell pairs couple electrically? | Micropatterned cardiac cell cultures |
How to Study the ventricular cardiac muscle cell action potential Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Patch-clamp (current clamp) | Action potential duration, amplitude, resting potential | Drug screening, gene function |
| Optical mapping | Spatiotemporal propagation of action potentials | Tissue-level arrhythmia studies |
| In silico simulation | Predicted action potential under varying conditions | Drug safety, mechanism exploration |
| CRISPR screen | Genes affecting action potential duration | Discovery of novel regulators |
| Calcium imaging | Intracellular calcium transients | Excitation-contraction coupling |
| ATP biosensor | Intracellular ATP dynamics | Metabolic regulation of AP |
| Micropatterned culture | Cell alignment and coupling | Physiological relevance |
| qPCR/Western blot | Ion channel expression levels | Validation of CRISPR edits |
Patch-Clamp Electrophysiology
Patch-clamp recordings in current-clamp mode directly measure the action potential waveform, including duration, amplitude, and resting potential, in isolated ventricular myocytes or hiPSC-CMs. This method is the gold standard for assessing GO:0086005 and can be combined with pharmacological agents to dissect ion currents.
Optical Mapping and Voltage-Sensitive Dyes
Optical mapping using voltage-sensitive dyes allows non-invasive recording of action potentials from multiple cells simultaneously, revealing propagation and heterogeneity in ventricular tissue. This technique is valuable for studying cell-to-cell coupling and arrhythmia mechanisms.
In Silico Modeling
Computational models of the ventricular action potential integrate ion current kinetics to simulate action potential duration, restitution, and drug effects. These models help predict arrhythmia risk and guide experimental design.
CRISPR-Based Genetic Screening
CRISPR knockout or activation screens in hiPSC-CMs can identify genes that regulate action potential duration, followed by validation with patch-clamp. This unbiased approach accelerates discovery of novel regulators of GO:0086005.
How CRISPR Can Be Used to Study GO:0086005 ventricular cardiac muscle cell action potential
Knockout
CRISPR knockout of ion channel genes such as KCNH2 or SCN5A in hiPSC-derived cardiomyocytes abolishes specific currents and prolongs or shortens the action potential, providing causal evidence for their role in GO:0086005. Knockout of MIR365 can also reveal its contribution to action potential duration.
Point Mutation
Introducing disease-associated point mutations (e.g., in KCNQ1 or KCNH2) via CRISPR base editing or homology-directed repair recreates patient-specific electrophysiological phenotypes, allowing study of variant effects on the action potential.
Knock-in
Knock-in of fluorescent tags or reporter genes into channel loci enables real-time visualization of channel trafficking and localization during the action potential. Knock-in of wild-type alleles can also correct disease phenotypes in patient-derived cells.
Overexpression
CRISPR activation (CRISPRa) or lentiviral overexpression of microRNAs such as miR-365 or ion channel subunits can enhance or suppress currents, revealing their sufficiency to alter action potential duration.
How EDITGENE Supports ventricular cardiac muscle cell action potential Research
Researchers studying ventricular cardiac muscle cell action potential-related genes often need to determine whether a candidate gene is causally involved in electrical remodeling or arrhythmia. EDITGENE provides end-to-end CRISPR services to create precisely engineered cell models that answer these questions.
Contact EDITGENE today to design your custom CRISPR model for ventricular cardiac muscle cell action potential research.
Frequently Asked Questions About ventricular cardiac muscle cell action potential
What is GO:0086005?
GO:0086005 is the Gene Ontology term for the action potential that occurs in a ventricular cardiac muscle cell, describing the electrical signal that triggers each heartbeat.
What genes are involved in ventricular cardiac muscle cell action potential?
Key genes include SCN5A, CACNA1C, KCNH2, KCNQ1, KCNJ2, and MIR365, among others.
How is the ventricular action potential measured?
It is typically measured using patch-clamp electrophysiology in isolated myocytes or hiPSC-derived cardiomyocytes, and can be modeled in silico.
What diseases are linked to abnormal ventricular action potential?
Long QT syndrome, Brugada syndrome, drug-induced arrhythmias, and heart failure are linked to action potential abnormalities.
What is the role of IKs in the ventricular action potential?
IKs is a slow delayed rectifier potassium current that contributes to repolarization reserve and prevents excessive action potential prolongation.
How does miR-365 affect the action potential?
miR-365 regulates human cardiac action potential duration, and its dysregulation can prolong the action potential.
Can CRISPR be used to study ventricular action potential genes?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models in cardiomyocytes are powerful tools to dissect gene function in GO:0086005.
What is the difference between ventricular and atrial action potentials?
Ventricular action potentials have a longer plateau phase and distinct ion current profiles compared to atrial cells, which is critical for coordinated contraction.
How does intracellular ATP affect the ventricular action potential?
Intracellular ATP dynamics during excitation-contraction coupling can modulate ion channels and pumps, influencing action potential stability.
What models are used to study ventricular action potential?
Models include primary ventricular myocytes, hiPSC-derived cardiomyocytes, micropatterned cultures, and in silico simulations.
Conclusion
GO:0086005, the ventricular cardiac muscle cell action potential, is a cornerstone of cardiac electrophysiology that integrates ion channel function, metabolic state, and regulatory signaling. Its precise control is essential for normal heart rhythm, and its dysregulation underlies numerous arrhythmic and heart failure conditions. By leveraging CRISPR-based models and advanced electrophysiological methods, researchers can uncover new mechanisms and therapeutic targets for cardiac disease.
References
- 1. Esfandyari D et al.. 2022. MicroRNA-365 regulates human cardiac action potential duration.. Nat Commun 13(1):220 PMID: 35017523
- 2. Howlett LA et al.. 2022. Action potential responses to changes in stimulation frequency and isoproterenol in rat ventricular myocytes.. Physiol Rep 10(2):e15166 PMID: 35076184
- 3. Jost N et al.. 2005. Restricting excessive cardiac action potential and QT prolongation: a vital role for IKs in human ventricular muscle.. Circulation 112(10):1392-9 PMID: 16129791
- 4. Zaniboni M. 2025. The electrophysiology of ventricular cell pairs.. Pflugers Arch 478(1):15 PMID: 41447424
- 5. Rhana P et al.. 2024. Fueling the heartbeat: Dynamic regulation of intracellular ATP during excitation-contraction coupling in ventricular myocytes.. Proc Natl Acad Sci U S A 121(25):e2318535121 PMID: 38865270
- 6. Zaniboni M. 2024. In silico analysis of ventricular action potential with a current-voltage-time representation: Thresholds, membrane resistance, repolarization reserve.. Physiol Rep 12(21):e70085 PMID: 39529595
- 7. Badie N et al.. 2009. Novel micropatterned cardiac cell cultures with realistic ventricular microstructure.. Biophys J 96(9):3873-85 PMID: 19413993
- 8. Jie LJ et al.. 2021. Mechanisms of gefitinib-induced QT prolongation.. Eur J Pharmacol 910:174441 PMID: 34474028
