GO:0106135 negative regulation of cardiac muscle cell contraction: Signaling Brakes, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0106135 describes any process that stops, prevents, or reduces the frequency, rate or extent of cardiac muscle cell contraction, a biological_process annotation in the Gene Ontology.
• The dominant molecular brakes on cardiac contraction are cAMP/PKA signaling nodes, including PDE4B, the PKA RIα subunit, and the Rad-Gβγ phosphoswitch that tunes L-type Ca2+ channel activity.
• β2-adrenergic receptor allosteric modulation by gut-microbe-derived phenylacetylglutamine illustrates how circulating metabolites can dampen or reshape adrenergic control of contraction.
• Calcium handling and sarcomere maturation are tightly coupled, so negative regulation of contraction intersects with cardiomyocyte maturation and regeneration programs.
• Dysregulated negative regulation of contraction underlies heart failure phenotypes, where blunted β-adrenergic responsiveness and maladaptive remodeling are common.
• CRISPR knockout, point-mutation, knock-in and overexpression models are the standard toolkit for dissecting which nodes causally restrain cardiac muscle cell contraction.
Description
GO:0106135, negative regulation of cardiac muscle cell contraction, is a Gene Ontology biological_process term defined as any process that stops, prevents, or reduces the frequency, rate or extent of cardiac muscle cell contraction. In practical terms, it collects the molecular brakes, feedback loops and signaling set-points that keep cardiomyocyte contraction from running unchecked. Because contraction is driven by calcium transients and sarcomere cycling, negative regulation is typically studied at the level of ion channels, kinases, phosphodiesterases and receptor complexes that tune those events. The term matters because loss of these brakes is a recurring theme in heart failure and arrhythmia biology, where adrenergic drive becomes maladaptive. Researchers use it to frame experiments on cAMP compartmentation, PKA substrate specificity and calcium channel phosphorylation, all of which determine how strongly a cardiomyocyte contracts. It also provides a controlled vocabulary for comparing phenotypes across knockout, point-mutation and overexpression models, which is essential for reproducible cardiac research.
negative regulation of cardiac muscle cell contraction At A Glance
| GO ID | GO:0106135 |
|---|---|
| GO term | negative regulation of cardiac muscle cell contraction |
| Ontology | biological_process |
| Synonym | None listed in QuickGO |
| Major function | Stops, prevents or reduces the frequency, rate or extent of cardiac muscle cell contraction |
| Parent term | regulation of cardiac muscle cell contraction |
| Related process | Adrenergic signaling, cAMP/PKA signaling, calcium handling |
| Representative regulators | PDE4B, PRKAR1A (PKA RIα), Rad, β2-adrenergic receptor |
| Disease relevance | Heart failure, maladaptive cardiac remodeling, arrhythmia susceptibility |
What Is GO:0106135?
In our own words, GO:0106135 captures any biological process whose net effect is to stop, prevent or reduce the frequency, rate or extent of cardiac muscle cell contraction. It is not a single pathway but a functional category: it includes inhibitory signaling cascades, phosphodiesterase-mediated cAMP degradation, phosphatase activity, and allosteric modulation of adrenergic receptors, provided the measurable outcome is reduced cardiomyocyte contraction. The term is a child of the broader regulation of cardiac muscle cell contraction and is annotated to biological_process in the Gene Ontology.
Why Is negative regulation of cardiac muscle cell contraction Important in Cell Biology?
Negative regulation of cardiac muscle cell contraction is important because the heart must continuously adjust its output, and excessive or poorly timed contraction is as dangerous as insufficient contraction. The cAMP/PKA axis is a central node: PDE4B overexpression blunts β-adrenergic responses and maladaptive remodeling in heart failure, while the PKA RIα subunit is essential for normal contractility and for preventing heart failure development. The Rad-Gβγ phosphoswitch provides a membrane-associated mechanism that controls adrenergic regulation of cardiac calcium channels, directly linking negative regulation to excitation-contraction coupling. In addition, gut-microbe-derived phenylacetylglutamine acts as an endogenous allosteric modulator of β2-adrenergic receptors, showing that negative regulation can be influenced by circulating metabolites. Together these findings make GO:0106135 a high-value term for cardiovascular drug target discovery and for interpreting CRISPR screens in cardiomyocytes.
• Provides a mechanistic framework for understanding how β-adrenergic drive is restrained in the heart.
• Explains why PDE4B overexpression blunts β-adrenergic response and maladaptive remodeling in heart failure.
• Links the PKA RIα subunit to contractility control and heart failure development.
• Connects calcium channel phosphorylation to contraction set-points via the Rad phosphoswitch.
• Highlights metabolite-driven allosteric modulation of β2-adrenergic receptors by phenylacetylglutamine.
• Intersects with cardiomyocyte maturation and regeneration through calcium-sarcomere interplay.
• Supports target validation for heart failure and arrhythmia drug discovery.
• Guides design of CRISPR knockout, point-mutation and overexpression experiments in cardiac models.
• Helps interpret transcriptomic and phosphoproteomic changes in failing myocardium.
• Offers a controlled vocabulary for cross-study comparison of contractility phenotypes.
What Happens During negative regulation of cardiac muscle cell contraction?
Adrenergic receptor-level braking
In simple terms: The first place the heart can put the brakes on is at the receptor that receives the 'speed up' signal.
β-adrenergic receptors initiate the cAMP signal that increases cardiac contraction, so negative regulation can begin with mechanisms that reduce receptor output. The gut-microbe-generated metabolite phenylacetylglutamine acts as an endogenous allosteric modulator of β2-adrenergic receptors, demonstrating that receptor-level modulation can reshape adrenergic signaling. Because this modulation occurs at the receptor itself, it represents an upstream node in GO:0106135 that can be studied with receptor-binding and cardiomyocyte contractility assays.
cAMP degradation by phosphodiesterases
In simple terms: If cAMP is the fuel pedal, phosphodiesterases are the brake that destroys the fuel before it can act.
Cyclic AMP is the principal second messenger that amplifies cardiac contraction, and its degradation by phosphodiesterases is a direct negative regulatory step. Cardiac overexpression of PDE4B blunts the β-adrenergic response and maladaptive remodeling in heart failure, showing that increasing cAMP breakdown reduces contractile responsiveness. This places PDE4B squarely within GO:0106135 and makes it a tractable target for CRISPR overexpression or knockout studies in cardiomyocytes.
PKA subunit composition and substrate specificity
In simple terms: The kinase that relays the signal has different parts, and changing those parts changes how strongly the heart contracts.
cAMP-dependent protein kinase (PKA) is the main effector of cAMP in cardiomyocytes, and its regulatory subunits determine where and how strongly the kinase acts. The RIα subunit of PKA is essential for regulating cardiac contractility and heart failure development, indicating that PKA composition is a determinant of negative regulation. Regulation of cardiac PKA signaling by cAMP and oxidants further shows that the kinase node is redox-sensitive and compartmentalized. Together, these findings define a PKA-centered layer of GO:0106135.
Membrane-associated phosphoswitch on calcium channels
In simple terms: A small protein called Rad can flip a switch on calcium channels, changing how much calcium enters and how hard the heart squeezes.
A membrane-associated phosphoswitch in Rad controls adrenergic regulation of cardiac calcium channels, providing a direct mechanism by which phosphorylation state tunes calcium influx and therefore contraction. Because calcium entry through L-type channels is a proximal trigger of contraction, the Rad phosphoswitch is a core negative regulatory node in GO:0106135. This mechanism is particularly amenable to point-mutation and knock-in studies that alter specific phosphorylation sites.
Calcium-sarcomere coupling and maturation
In simple terms: Calcium and the contractile machinery talk to each other, and this conversation sets how mature and how responsive a heart cell is.
Interplay between calcium and sarcomeres directs cardiomyocyte maturation during regeneration, showing that negative regulation of contraction is embedded in developmental and regenerative programs. Zone-specific regulation of cardiac myosin further indicates that the contractile apparatus itself is regionally tuned. These findings extend GO:0106135 beyond acute signaling into maturation and structural remodeling.
Key Genes Involved in GO:0106135 negative regulation of cardiac muscle cell contraction
The following genes and proteins are experimentally implicated in negative regulation of cardiac muscle cell contraction or in the adrenergic and calcium-handling pathways that define it.
| Gene | Major Role | Research Relevance |
|---|---|---|
| PDE4B | cAMP phosphodiesterase that degrades cAMP and blunts β-adrenergic signaling | Cardiac overexpression blunts β-adrenergic response and maladaptive remodeling in heart failure |
| PRKAR1A | Regulatory subunit RIα of cAMP-dependent protein kinase (PKA) | Essential for regulating cardiac contractility and heart failure development |
| RAD | Membrane-associated phosphoswitch controlling adrenergic regulation of cardiac calcium channels | Point-mutation and knock-in studies of calcium channel regulation |
| ADRB2 | β2-adrenergic receptor, target of allosteric modulation | Modulated by gut-microbe-derived phenylacetylglutamine |
| ADRB1 | β1-adrenergic receptor, canonical driver of cardiac contractility | Central to adrenergic control of contraction |
| PRKACA | Catalytic subunit of PKA | Effector of cAMP signaling in cardiomyocytes |
| CACNA1C | L-type calcium channel alpha-1C subunit | Target of Rad phosphoswitch regulation |
| MYH7 | Beta-myosin heavy chain, sarcomeric motor | Zone-specific regulation of cardiac myosin |
| MYH6 | Alpha-myosin heavy chain, sarcomeric motor | Sarcomere maturation and regeneration studies |
| TNNT2 | Cardiac troponin T, thin filament regulator | Calcium-sarcomere coupling in cardiomyocyte maturation |
| RYR2 | Ryanodine receptor 2, sarcoplasmic reticulum calcium release channel | Calcium handling in contraction and regeneration |
| ATP2A2 | SERCA2a calcium pump | Calcium reuptake and contractile relaxation |
| PLN | Phospholamban, SERCA2a inhibitor | PKA substrate in calcium handling |
| TNNI3 | Cardiac troponin I, PKA substrate | PKA signaling and contractility regulation |
| MYBPC3 | Myosin binding protein C | Sarcomere regulation and cardiac myosin studies |
| GNG | G-protein gamma subunit partner of Rad | Rad-Gβγ phosphoswitch mechanism |
| PDE4D | cAMP phosphodiesterase family member | cAMP compartmentation in cardiomyocytes |
| PRKAR2A | Type II PKA regulatory subunit | PKA signaling compartmentation |
How Is negative regulation of cardiac muscle cell contraction Regulated?
Negative regulation of cardiac muscle cell contraction is itself regulated at multiple levels. cAMP availability is controlled by the balance between adenylyl cyclase activity and phosphodiesterase-mediated degradation, with PDE4B overexpression sufficient to blunt β-adrenergic responses. PKA activity is tuned by regulatory subunit composition, and the RIα subunit is essential for normal contractility and for preventing heart failure development. The kinase is also sensitive to oxidants, adding a redox layer to cAMP-PKA signaling. At the membrane, the Rad-Gβγ phosphoswitch integrates phosphorylation signals to control calcium channel activity. Finally, receptor-level allosteric modulation by metabolites such as phenylacetylglutamine can reshape adrenergic output. Together these layers form a tunable system in which negative regulation can be strengthened or weakened by genetic and pharmacological interventions.
negative regulation of cardiac muscle cell contraction and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| PDE4B | Heart failure with blunted β-adrenergic response | Cardiac overexpression and knockout in cardiomyocytes |
| PRKAR1A | Heart failure development and contractility regulation | Knockout and point-mutation models of PKA RIα |
| RAD | Calcium channel dysregulation and arrhythmia susceptibility | Phosphosite point-mutation and knock-in models |
| ADRB2 | Metabolite-modulated adrenergic signaling | Allosteric modulation assays with phenylacetylglutamine |
| MYH7 | Sarcomeric cardiomyopathy biology | Zone-specific myosin regulation studies |
Heart failure and maladaptive remodeling
Heart failure is characterized by blunted β-adrenergic responsiveness and maladaptive remodeling, and negative regulators of contraction are directly implicated. Cardiac overexpression of PDE4B blunts the β-adrenergic response and maladaptive remodeling in heart failure, suggesting that enhancing cAMP degradation can be protective or maladaptive depending on context. The PKA RIα subunit is essential for regulating cardiac contractility and heart failure development, linking PKA composition to disease progression. These findings make GO:0106135 a framework for interpreting contractility phenotypes in heart failure models.
Arrhythmia susceptibility and calcium channel dysregulation
Because calcium entry determines both contraction strength and action potential duration, negative regulation of calcium channels is relevant to arrhythmia. The membrane-associated phosphoswitch in Rad controls adrenergic regulation of cardiac calcium channels, and its dysregulation could alter excitation-contraction coupling. PKA signaling, which is redox-sensitive, further modulates calcium handling proteins and contractility. Studying GO:0106135 therefore helps connect molecular brakes to arrhythmia risk.
Cardiomyocyte maturation and regeneration
Interplay between calcium and sarcomeres directs cardiomyocyte maturation during regeneration, indicating that negative regulation of contraction is part of developmental programs. Zone-specific regulation of cardiac myosin shows that the contractile apparatus is regionally specialized. These observations suggest that manipulating negative regulatory nodes could influence maturation of stem-cell-derived cardiomyocytes for regenerative medicine.
Metabolite-driven modulation of adrenergic signaling
Gut microbe-generated phenylacetylglutamine is an endogenous allosteric modulator of β2-adrenergic receptors, revealing a microbiome-heart axis that can influence contraction. This expands the disease relevance of GO:0106135 beyond classical cardiovascular genetics to include metabolic and microbial inputs.
From negative regulation of cardiac muscle cell contraction-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of PDE4B increase contractile responsiveness? | PDE4B knockout cardiomyocytes |
| Does PDE4B overexpression blunt β-adrenergic signaling? | Cardiac overexpression model |
| Is PKA RIα required for normal contractility? | PRKAR1A knockout or knockdown |
| Which Rad phosphorylation sites control calcium channels? | Point-mutation knock-in of Rad phosphosites |
| Can metabolite modulation of β2-adrenergic receptors alter contraction? | ADRB2 allosteric modulation assays |
| How do calcium-sarcomere interactions affect maturation? | Cardiomyocyte maturation and regeneration models |
How to Study the negative regulation of cardiac muscle cell contraction Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Cardiomyocyte shortening assay | Contraction amplitude and kinetics | Testing negative regulators such as PDE4B |
| Calcium imaging | Calcium transient amplitude and decay | Assessing calcium handling changes |
| Patch-clamp electrophysiology | L-type calcium channel activity | Rad phosphoswitch studies |
| FRET cAMP sensors | Real-time cAMP levels | PKA signaling and PDE4B effects |
| Phosphoproteomics | Site-specific phosphorylation changes | Mapping PKA and Rad substrates |
| RNA sequencing | Transcriptional changes in myocardium | Heart failure and maturation studies |
| CRISPR functional screen | Causal effect of gene loss on contraction | Discovering new negative regulators |
| Immunoblotting | Protein expression and subunit composition | PKA RIα and PDE4B expression |
Contractility and calcium imaging
Measuring contraction and calcium transients is the most direct way to assess GO:0106135. Cardiomyocyte shortening, calcium imaging and patch-clamp of L-type calcium channels can quantify how negative regulators such as Rad or PDE4B change excitation-contraction coupling. These assays are typically paired with adrenergic stimulation to reveal blunted responses.
cAMP and PKA activity assays
Because cAMP/PKA signaling is central to negative regulation, FRET-based cAMP sensors and PKA substrate phosphorylation assays are widely used. Regulation of cardiac PKA signaling by cAMP and oxidants highlights the importance of measuring both second messenger levels and downstream phosphorylation. PKA regulatory subunit composition can be assessed by immunoblotting and isoform-specific probes.
Phosphoproteomics and targeted phosphorylation analysis
The Rad phosphoswitch and PKA substrates require site-specific phosphorylation measurements. Phosphoproteomics and targeted mass spectrometry can identify changes at calcium channel and sarcomeric protein sites after genetic or pharmacological perturbation. These methods help map which nodes within GO:0106135 are engaged in a given model.
Transcriptomic and functional genomic profiling
RNA sequencing and CRISPR screening can nominate new negative regulators of contraction. Transcriptomic profiling of failing myocardium and cardiomyocyte maturation models provides context for candidate genes. Functional genomic screens can then test whether candidate genes causally reduce contraction.
How CRISPR Can Be Used to Study GO:0106135 negative regulation of cardiac muscle cell contraction
Knockout
CRISPR knockout is used to remove candidate negative regulators and test whether contraction increases. For example, knocking out PDE4B or PRKAR1A can reveal their contribution to cAMP set-points and contractility. Knockout models are also useful for validating hits from functional genomic screens.
Point Mutation
Point mutation is essential for dissecting phosphoswitches such as Rad, where individual phosphorylation sites control calcium channel activity. CRISPR point-mutation models allow precise testing of whether a specific residue is required for negative regulation of contraction. Similar approaches can be applied to PKA and phospholamban sites.
Knock-in
Knock-in models can introduce disease-associated variants or tagged alleles to track protein localization and function. Tagged knock-in of PKA subunits or calcium channel components enables imaging and interaction studies in cardiomyocytes. Knock-in of phospho-mimetic or phospho-dead Rad alleles can directly test the phosphoswitch hypothesis.
Overexpression
Overexpression is a powerful way to strengthen negative regulation. Cardiac overexpression of PDE4B blunts β-adrenergic response and maladaptive remodeling, demonstrating that increasing a negative regulator can change disease phenotypes. Overexpression of PKA regulatory subunits or mutant Rad can similarly test gain-of-function effects.
How EDITGENE Supports negative regulation of cardiac muscle cell contraction Research
Researchers studying negative regulation of cardiac muscle cell contraction-related genes often need to determine whether a candidate gene is causally involved in restraining contractility, and at which signaling node. This requires precise genetic models that can isolate loss-of-function, gain-of-function and phosphosite-specific effects in cardiomyocytes. EDITGENE provides end-to-end CRISPR services to build and characterize those models, from knockout to knock-in and overexpression, supported by library screening and bioinformatics.
Contact EDITGENE today to design your custom CRISPR model for negative regulation of cardiac muscle cell contraction research.
Frequently Asked Questions About negative regulation of cardiac muscle cell contraction
What is GO:0106135 negative regulation of cardiac muscle cell contraction?
GO:0106135 is a Gene Ontology biological_process term defined as any process that stops, prevents, or reduces the frequency, rate or extent of cardiac muscle cell contraction.
What genes are involved in negative regulation of cardiac muscle cell contraction?
Key genes include PDE4B, PRKAR1A (PKA RIα), RAD, ADRB2 and components of the cAMP/PKA and calcium handling machinery.
How does PDE4B affect cardiac contraction?
Cardiac overexpression of PDE4B blunts the β-adrenergic response and maladaptive remodeling in heart failure by degrading cAMP.
What is the role of PKA RIα in heart failure?
The RIα subunit of cAMP-dependent protein kinase is essential for regulating cardiac contractility and heart failure development.
What is the Rad phosphoswitch?
Rad is a membrane-associated protein whose phosphorylation state controls adrenergic regulation of cardiac calcium channels.
Can gut microbes influence cardiac contraction?
Yes, gut microbe-generated phenylacetylglutamine acts as an endogenous allosteric modulator of β2-adrenergic receptors.
How do calcium and sarcomeres interact during cardiomyocyte maturation?
Interplay between calcium and sarcomeres directs cardiomyocyte maturation during regeneration.
What research methods study negative regulation of contraction?
Common methods include cardiomyocyte shortening assays, calcium imaging, patch-clamp, FRET cAMP sensors, phosphoproteomics and RNA sequencing.
How is PKA signaling regulated in the heart?
Cardiac PKA signaling is regulated by cAMP levels and oxidants, which affect kinase activity and substrate phosphorylation.
What CRISPR models are used for cardiac contractility research?
Knockout, point-mutation, knock-in and overexpression models are used to test causal roles of genes such as PDE4B, PRKAR1A and RAD.
Conclusion
GO:0106135 negative regulation of cardiac muscle cell contraction provides a precise vocabulary for the molecular brakes that restrain cardiomyocyte contraction. Experimental work has placed cAMP/PKA signaling, PDE4B, PKA RIα and the Rad phosphoswitch at the center of this process, with additional input from receptor-level allosteric modulation and calcium-sarcomere coupling. Because these nodes are directly linked to heart failure and arrhythmia biology, they are high-value targets for CRISPR-based functional studies. EDITGENE supports researchers in building the knockout, point-mutation, knock-in and overexpression models needed to test causality and mechanism.
References
- 2. Papa A et al.. 2024. A membrane-associated phosphoswitch in Rad controls adrenergic regulation of cardiac calcium channels.. J Clin Invest 134(5) PMID: 38227371
- 3. Saha PP et al.. 2024. Gut microbe-generated phenylacetylglutamine is an endogenous allosteric modulator of β2-adrenergic receptors.. Nat Commun 15(1):6696 PMID: 39107277
- 4. Nguyen PD et al.. 2023. Interplay between calcium and sarcomeres directs cardiomyocyte maturation during regeneration.. Science 380(6646):758-764 PMID: 37200435
- 5. Karam S et al.. 2020. Cardiac Overexpression of PDE4B Blunts β-Adrenergic Response and Maladaptive Remodeling in Heart Failure.. Circulation 142(2):161-174 PMID: 32264695
- 6. Bedioune I et al.. 2024. Essential Role of the RIα Subunit of cAMP-Dependent Protein Kinase in Regulating Cardiac Contractility and Heart Failure Development.. Circulation 150(25):2031-2045 PMID: 39355927
- 7. Nelson SR. 2025. Resolving zone-specific regulation of cardiac myosin.. J Gen Physiol 157(6) PMID: 40876855
- 8. Cuello F et al.. 2021. Regulation of Cardiac PKA Signaling by cAMP and Oxidants.. Antioxidants (Basel) 10(5) PMID: 33923287
