GO:0035226 glutamate-cysteine ligase catalytic subunit binding: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0035226 describes the molecular function of binding to the catalytic subunit of glutamate-cysteine ligase (GCLC), the rate-limiting enzyme in glutathione synthesis.
• This binding event regulates GCLC activity and glutathione homeostasis, which is critical for cellular defense against oxidative stress.
• The catalytic subunit GCLC contains an essential cysteine residue (Cys553) whose modification affects enzyme activity and binding interactions.
• Dysregulation of GCLC binding partners is implicated in diabetic nephropathy, acetaminophen-induced hepatotoxicity, and renal cell carcinoma.
• Transcriptional regulation of GCLC involves AP-1 and NF-kappaB binding to its promoter, linking stress signaling to glutathione synthesis.
• CRISPR-based models (knockout, point mutation, knock-in, overexpression) enable precise dissection of GCLC binding interactions in disease contexts.
Description
Glutamate-cysteine ligase catalytic subunit binding (GO:0035226) is a molecular function defined as the binding to the catalytic subunit of glutamate-cysteine ligase (GCLC), the enzyme that catalyzes the first and rate-limiting step of glutathione (GSH) synthesis. This binding event is central to the regulation of GSH homeostasis, which protects cells from oxidative damage and maintains redox balance. Researchers study this term to understand how protein-protein interactions modulate GCLC activity and how their disruption contributes to disease. The catalytic subunit GCLC contains critical cysteine residues, such as Cys553, that are essential for its function and are targets for regulatory modifications. Binding partners can influence GCLC stability, subcellular localization, or catalytic efficiency, thereby impacting cellular responses to stress. Given the broad role of glutathione in health and disease, elucidating the mechanisms of GCLC binding is of significant biomedical interest.
glutamate-cysteine ligase catalytic subunit binding At A Glance
| GO ID | GO:0035226 |
|---|---|
| GO term | glutamate-cysteine ligase catalytic subunit binding |
| Ontology | molecular_function |
| Synonym | none |
| Major function | Binding to the catalytic subunit of glutamate-cysteine ligase, regulating glutathione synthesis |
| Related enzyme | Glutamate-cysteine ligase catalytic subunit (GCLC) |
| Pathological relevance | Oxidative stress-related diseases, including diabetic nephropathy, hepatotoxicity, and cancer |
| Experimental evidence | Site-directed mutagenesis, virtual screening, and molecular docking studies |
What Is GO:0035226?
GO:0035226 is a molecular function term that describes the selective interaction of a protein or other molecule with the catalytic subunit of glutamate-cysteine ligase (GCLC). This binding event is distinct from the enzymatic activity of GCLC itself; it refers to the physical association that may regulate GCLC's catalytic activity, stability, or localization. The term is supported by experimental evidence showing that various proteins and small molecules can bind to GCLC and modulate glutathione synthesis.
Why Is glutamate-cysteine ligase catalytic subunit binding Important in Cell Biology?
Glutamate-cysteine ligase catalytic subunit binding is crucial because it directly influences the rate of glutathione synthesis, the primary antioxidant in cells. Dysregulation of this binding can lead to oxidative stress, contributing to the pathogenesis of numerous diseases such as diabetic nephropathy, acetaminophen-induced liver injury, and renal cell carcinoma. Understanding the molecular details of these interactions can reveal new therapeutic targets and biomarkers for oxidative stress-related conditions.
• Regulates the rate-limiting step of glutathione synthesis, affecting cellular redox balance.
• Modulates cellular defense against oxidative stress and xenobiotic toxicity.
• Implicated in diabetic nephropathy through oxidative stress mechanisms.
• Plays a role in acetaminophen-induced hepatotoxicity by influencing glutathione availability.
• Associated with renal cell carcinoma progression and ferroptosis resistance.
• Transcriptional regulation by AP-1 and NF-kappaB links stress signals to GCLC expression.
• Potential target for small-molecule inhibitors, as shown in Tribolium castaneum studies.
• Essential for cochlear protection against acoustic overstimulation.
• Provides a model for studying protein-protein interactions in redox regulation.
• Enables CRISPR-based functional genomics of glutathione metabolism.
What Happens During glutamate-cysteine ligase catalytic subunit binding?
Recognition and Association
In simple terms: A protein or molecule recognizes and attaches to the catalytic subunit of glutamate-cysteine ligase.
The binding event begins with the specific recognition of GCLC by a partner protein or small molecule. This interaction often involves electrostatic and hydrophobic contacts, and can be influenced by post-translational modifications of GCLC, such as modification of cysteine residues. For example, site-directed mutagenesis studies have identified Cys553 as critical for GCLC function and potentially for binding interactions.
Conformational Changes and Activity Modulation
In simple terms: Binding causes the enzyme to change shape, which can alter its activity.
Upon binding, GCLC may undergo conformational changes that affect its catalytic efficiency or its interaction with the modifier subunit (GCLM). Such changes can either enhance or inhibit glutathione synthesis, depending on the binding partner. For instance, binding of small-molecule inhibitors can block the active site or induce structural shifts that reduce activity.
Regulation of Glutathione Synthesis
In simple terms: The binding event controls how much glutathione the cell makes.
Because GCLC catalyzes the first and rate-limiting step of glutathione synthesis, its binding partners can directly influence cellular glutathione levels. This regulation is critical under oxidative stress conditions, where rapid upregulation of glutathione is needed. Transcriptional induction of GCLC via AP-1 and NF-kappaB also increases the pool of GCLC available for binding.
Integration with Stress Signaling Pathways
In simple terms: Binding is connected to cellular stress signals that tell the cell to make more antioxidants.
GCLC binding is integrated with stress-responsive signaling pathways. For example, the NRF2 pathway, which is activated by oxidative stress, upregulates GCLC expression and may also influence its interactions with binding partners. In macrophages, the TXNIP-mediated CYLD-NRF2-OASL1 axis affects stress-induced liver inflammation and cell death, highlighting the interplay between GCLC regulation and inflammatory signaling.
Key Genes Involved in GO:0035226 glutamate-cysteine ligase catalytic subunit binding
The following genes and proteins are key players in glutamate-cysteine ligase catalytic subunit binding and its regulatory network.
| Gene | Major Role | Research Relevance |
|---|---|---|
| GCLC | Catalytic subunit of glutamate-cysteine ligase; binds partners to regulate glutathione synthesis | Core enzyme in glutathione metabolism; target for mutagenesis and inhibitor studies |
| GCLM | Modifier subunit of glutamate-cysteine ligase; modulates GCLC activity | Regulates GCLC catalytic efficiency and is often co-expressed |
| NFE2L2 (NRF2) | Transcription factor that upregulates GCLC expression under oxidative stress | Master regulator of antioxidant response; linked to GCLC binding regulation |
| JUN (AP-1) | Transcription factor that binds GCLC promoter and enhances expression | Mediates stress-induced GCLC upregulation in cochlea |
| NFKB1 | Transcription factor that binds GCLC promoter and enhances expression | Involved in inflammatory signaling and GCLC regulation |
| TXNIP | Thioredoxin-interacting protein; regulates NRF2 and stress responses | Links oxidative stress to GCLC regulation in liver inflammation |
| CYLD | Deubiquitinase that modulates NRF2 signaling | Affects GCLC expression and glutathione synthesis |
| OASL1 | Interferon-induced protein involved in stress responses | Part of the TXNIP-CYLD-NRF2 axis affecting GCLC |
| CENPT | Centromere protein T; enhances glutathione synthesis and prevents ferroptosis | Regulates GCLC and glutathione levels in renal cell carcinoma |
| SLC7A11 | Cystine/glutamate antiporter; supplies cysteine for glutathione synthesis | Indirectly affects GCLC substrate availability |
| GPX4 | Glutathione peroxidase 4; uses glutathione to detoxify lipid peroxides | Downstream effector of glutathione; related to ferroptosis |
| KEAP1 | Negative regulator of NRF2; controls GCLC expression | Modulates GCLC levels and binding interactions |
| ATF4 | Transcription factor in integrated stress response; regulates GCLC | Links amino acid stress to glutathione synthesis |
| CASPASE-1 | Inflammatory caspase; may influence GCLC cleavage | Potential role in stress-induced cell death |
| IL-1B | Pro-inflammatory cytokine; induces oxidative stress | May indirectly affect GCLC binding via NRF2 |
| TNF | Pro-inflammatory cytokine; modulates glutathione levels | Links inflammation to GCLC regulation |
| MAPK1 (ERK2) | Kinase in MAPK pathway; may phosphorylate GCLC | Potential regulator of GCLC binding |
| RELA (NF-kB p65) | Transcription factor subunit; binds GCLC promoter | Mediates NF-kappaB-dependent GCLC expression |
How Is glutamate-cysteine ligase catalytic subunit binding Regulated?
The expression and activity of GCLC are regulated at multiple levels. Transcriptionally, the GCLC promoter contains binding sites for AP-1 and NF-kappaB, which mediate induction by stress stimuli such as acoustic overstimulation. The NRF2 pathway is a major regulator; under oxidative stress, NRF2 dissociates from KEAP1 and translocates to the nucleus to activate GCLC transcription. Additionally, the TXNIP-CYLD-NRF2-OASL1 axis modulates GCLC expression in liver inflammation. Post-translational modifications, such as cysteine oxidation, can affect GCLC activity and its interactions with binding partners. The availability of substrates (cysteine and glutamate) also influences glutathione synthesis rates.
glutamate-cysteine ligase catalytic subunit binding and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| GCLC | Diabetic nephropathy | Knockout or overexpression in renal mesangial cells |
| GCLC | Acetaminophen-induced hepatotoxicity | Liver-specific knockout or knock-in mice |
| CENPT | Renal cell carcinoma | Knockout or overexpression in RCC cell lines |
| GCLC | Noise-induced hearing loss | Cochlear cell lines or animal models |
| GCLC | Ferroptosis resistance | Cancer cell lines with GPX4 inhibition |
Diabetic Nephropathy
Oxidative stress is a key mediator of diabetic nephropathy, and GCLC binding partners that regulate glutathione synthesis may influence disease progression. Chinese medicines used for diabetic nephropathy management often target oxidative stress pathways, including GCLC regulation.
Acetaminophen-Induced Hepatotoxicity
Acetaminophen overdose depletes glutathione, leading to hepatocyte death. GCLC binding interactions that modulate glutathione synthesis are critical in determining susceptibility to liver injury. Recommendations for using the acetaminophen model emphasize the importance of glutathione dynamics.
Renal Cell Carcinoma
CENPT enhances glutathione synthesis by regulating GCLC, protecting renal cell carcinoma cells from ferroptosis. This highlights the role of GCLC binding in cancer cell survival and potential therapeutic targeting.
Hearing Loss
Acoustic overstimulation induces GCLC expression in the cochlea via AP-1 and NF-kappaB, suggesting that GCLC binding partners may protect against noise-induced hearing loss.
From glutamate-cysteine ligase catalytic subunit binding-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does GCLC binding regulate glutathione synthesis? | GCLC knockout cells with rescue by wild-type or binding-deficient mutants |
| Which residues are critical for GCLC binding? | Point mutation of cysteine residues (e.g., C553S) via CRISPR |
| How does a binding partner affect GCLC localization? | Knock-in of tagged GCLC (e.g., GFP) for imaging |
| Can overexpression of a binding partner increase glutathione? | Overexpression of candidate binding proteins in cell lines |
| What is the role of GCLC binding in ferroptosis? | Knockout of CENPT in RCC cells followed by ferroptosis induction |
| How does stress signaling affect GCLC binding? | Knockout of NRF2 or AP-1 followed by oxidative stress |
How to Study the glutamate-cysteine ligase catalytic subunit binding Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Co-immunoprecipitation | Physical interaction between GCLC and partner proteins | Validation of binding partners in cell lysates |
| Site-directed mutagenesis | Effect of specific amino acid changes on GCLC function | Identification of critical residues like Cys553 |
| Molecular docking | Predicted binding affinity and mode of small molecules to GCLC | Virtual screening for inhibitors |
| Luciferase reporter assay | Transcriptional activity of GCLC promoter | Analysis of AP-1/NF-kappaB regulation |
| CRISPR knockout | Loss-of-function phenotype of GCLC or partners | Study of glutathione synthesis and oxidative stress |
| CRISPR knock-in | Tagged or mutant GCLC expression | Imaging and interaction studies |
| RNA-seq | Global gene expression changes upon GCLC modulation | Pathway analysis in disease models |
| Proteomics | Protein interaction network of GCLC | Identification of novel binding partners |
Site-Directed Mutagenesis and Binding Assays
Site-directed mutagenesis is used to identify critical residues in GCLC that mediate binding, such as Cys553. Binding assays, including co-immunoprecipitation and pull-down, can confirm interactions between GCLC and candidate partners.
Virtual Screening and Molecular Docking
High-throughput virtual screening and molecular docking have been used to identify small-molecule inhibitors that bind to GCLC, as demonstrated in Tribolium castaneum. These methods predict binding modes and affinities, guiding experimental validation.
Transcriptional Reporter Assays
Reporter assays using the GCLC promoter region can measure transcriptional activation by AP-1 and NF-kappaB. This helps link stress signaling to GCLC expression and subsequent binding events.
CRISPR-Cas9 Genome Editing
CRISPR-Cas9 knockout, point mutation, and knock-in models enable precise manipulation of GCLC and its binding partners to study their roles in glutathione synthesis and disease.
How CRISPR Can Be Used to Study GO:0035226 glutamate-cysteine ligase catalytic subunit binding
Knockout
CRISPR knockout of GCLC or its binding partners can reveal their essential roles in glutathione synthesis and oxidative stress responses. For example, knockout of CENPT in renal cell carcinoma cells reduces glutathione levels and increases ferroptosis sensitivity.
Point Mutation
Point mutations, such as C553S in GCLC, can be introduced via CRISPR to study the functional significance of specific residues in binding and catalysis. This approach helps dissect the molecular determinants of GCLC interactions.
Knock-in
Knock-in of tagged GCLC (e.g., GFP or FLAG) allows for live-cell imaging and affinity purification of binding complexes. This can identify dynamic changes in GCLC localization and interactions under stress.
Overexpression
Overexpression of GCLC or candidate binding partners via CRISPR activation or lentiviral delivery can enhance glutathione synthesis and protect against oxidative injury. This is useful for testing therapeutic potential in disease models.
How EDITGENE Supports glutamate-cysteine ligase catalytic subunit binding Research
Researchers studying glutamate-cysteine ligase catalytic subunit binding-related genes often need to determine whether a candidate gene is causally involved in glutathione regulation, oxidative stress responses, or disease phenotypes. EDITGENE provides a comprehensive suite of CRISPR-based services to accelerate this discovery process.
Contact EDITGENE today to design your custom CRISPR model for glutamate-cysteine ligase catalytic subunit binding research.
Frequently Asked Questions About glutamate-cysteine ligase catalytic subunit binding
What is GO:0035226?
GO:0035226 is a Gene Ontology molecular function term defined as binding to the catalytic subunit of glutamate-cysteine ligase (GCLC), the rate-limiting enzyme in glutathione synthesis.
What genes are involved in glutamate-cysteine ligase catalytic subunit binding?
Key genes include GCLC, GCLM, NFE2L2 (NRF2), JUN, NFKB1, TXNIP, CYLD, OASL1, and CENPT, among others.
How does GCLC binding affect glutathione synthesis?
Binding to GCLC can modulate its catalytic activity, stability, or localization, thereby influencing the rate of glutathione production and cellular redox balance.
Which diseases are associated with GCLC binding?
Diseases include diabetic nephropathy, acetaminophen-induced hepatotoxicity, renal cell carcinoma, and noise-induced hearing loss.
What experimental methods study GCLC binding?
Common methods include co-immunoprecipitation, site-directed mutagenesis, molecular docking, reporter assays, and CRISPR-based editing.
How is GCLC expression regulated?
GCLC transcription is regulated by AP-1 and NF-kappaB binding to its promoter, and by the NRF2 pathway under oxidative stress.
What is the role of Cys553 in GCLC?
Cys553 is a critical cysteine residue in human GCLC; its modification affects enzyme activity and potentially binding interactions.
Can CRISPR be used to study GCLC binding?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models enable precise dissection of GCLC binding interactions and their functional consequences.
What is the connection between GCLC and ferroptosis?
GCLC-mediated glutathione synthesis protects cells from ferroptosis; loss of GCLC or its regulators can sensitize cells to ferroptotic death.
How does oxidative stress affect GCLC binding?
Oxidative stress activates NRF2 and other transcription factors, increasing GCLC expression and potentially altering its interactions with binding partners.
Conclusion
Glutamate-cysteine ligase catalytic subunit binding (GO:0035226) is a fundamental molecular function that regulates glutathione synthesis and cellular redox homeostasis. Its dysregulation is linked to diverse pathologies, including diabetic nephropathy, hepatotoxicity, and cancer. Understanding the mechanisms and binding partners of GCLC offers opportunities for therapeutic intervention. EDITGENE's CRISPR services provide powerful tools to investigate these interactions and accelerate discovery in oxidative stress research.
References
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- 2. Jaeschke H et al.. 2021. Recommendations for the use of the acetaminophen hepatotoxicity model for mechanistic studies and how to avoid common pitfalls.. Acta Pharm Sin B 11(12):3740-3755 PMID: 35024303
- 3. Kim K et al.. 2024. Novel Inhibitor of Glutamate-Cysteine Ligase Catalytic Subunit against Tribolium castaneum: High-Throughout Virtual Screening, Molecular Docking and Dynamics Simulation, and Bioassay.. J Agric Food Chem 72(32):17813-17823 PMID: 39080857
- 4. Zhan Y et al.. 2022. Novel role of macrophage TXNIP-mediated CYLD-NRF2-OASL1 axis in stress-induced liver inflammation and cell death.. JHEP Rep 4(9):100532 PMID: 36035360
- 5. Tu Z et al.. 1998. Identification of an important cysteine residue in human glutamate-cysteine ligase catalytic subunit by site-directed mutagenesis.. Biochem J 336 ( Pt 3)(Pt 3):675-80 PMID: 9841880
- 6. Yang H et al.. 2025. CENPT prevents renal cell carcinoma against ferroptosis by enhancing the synthesis of glutathione.. Cell Death Dis 16(1):517 PMID: 40651948
- 7. Nagashima R et al.. 2007. Acoustic overstimulation facilitates the expression of glutamate-cysteine ligase catalytic subunit probably through enhanced DNA binding of activator protein-1 and/or NF-kappaB in the murine cochlea.. Neurochem Int 51(2-4):209-15 PMID: 17559975
- 8. Yang H et al.. 2001. Cloning and characterization of the 5'-flanking region of the rat glutamate-cysteine ligase catalytic subunit.. Biochem J 357(Pt 2):447-55 PMID: 11439094
