GO:0036402 proteasome-activating activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0036402 (proteasome-activating activity) is a molecular function defined as ATP hydrolysis coupled to protein substrate unfolding and opening of the core proteasome channel.
• The activity is executed by AAA+ ATPases of the 19S regulatory particle, which gate the 20S proteasome and translocate unfolded substrates into the catalytic chamber.
• Proteasome-activating activity is dynamically regulated; heat shock stably activates 26S proteasomes and increases ubiquitination and degradation.
• Loss of proteasome activation is linked to neurodegeneration, including FBXO11-deficiency and amyloid-induced proteasome impairment.
• Pharmacological or genetic proteasome activation can mitigate disease phenotypes, such as ferroptosis in cardiac ischaemia/reperfusion and amyloid toxicity.
• CRISPR knockout, point-mutation, knock-in and overexpression models are essential to dissect the causal role of proteasome-activating ATPases in disease.
Description
GO:0036402, proteasome-activating activity, is a molecular function that couples ATP hydrolysis to the unfolding of protein substrates and the opening of the core proteasome channel. This activity is essential for the 26S proteasome to degrade ubiquitinated proteins, a central process in protein quality control, cell-cycle progression and stress responses. Researchers study this term because defects in proteasome activation contribute to neurodegeneration, cancer and cardiac injury, and because modulating this activity is a promising therapeutic strategy. The QuickGO definition specifies the reaction ATP + H2O = ADP + phosphate, which promotes substrate unfolding and channel opening of the core proteasome. This article integrates authoritative ontology data with verified PubMed literature to provide a research-grade overview of GO:0036402, its mechanisms, key genes, disease links and experimental methods.
proteasome-activating activity At A Glance
| GO ID | GO:0036402 |
|---|---|
| GO term | proteasome-activating activity |
| Ontology | molecular_function |
| Synonym | ATPase involved in positive regulation of proteasomal protein catabolic process; proteasomal ATPase activity; proteasome-activating ATPase activity; proteasome channel gating activity; proteasome channel opening activity |
| Definition | Catalysis of the reaction: ATP + H2O = ADP + phosphate, which promotes unfolding of protein substrates, and channel opening of the core proteasome. |
| Major function | ATP-dependent unfolding of substrates and gating of the 20S proteasome channel for protein degradation. |
| Related process | Positive regulation of proteasomal protein catabolic process. |
| Cellular context | 26S proteasome regulatory particle (19S). |
What Is GO:0036402?
In our own words, GO:0036402 describes the ATP-dependent enzymatic activity that prepares protein substrates for degradation by the proteasome. It hydrolyzes ATP to ADP and phosphate, and this energy is used to unfold substrate proteins and to open the channel of the 20S core proteasome, allowing unfolded polypeptides to enter the catalytic chamber. This activity is often referred to as proteasomal ATPase activity, proteasome-activating ATPase activity, or proteasome channel gating activity.
Why Is proteasome-activating activity Important in Cell Biology?
Proteasome-activating activity is critical because it controls the rate-limiting step of ATP-dependent protein degradation, which regulates nearly every cellular process, including cell-cycle progression, apoptosis, immune response and protein quality control. Dysregulation of this activity is implicated in cancer, neurodegeneration and cardiac disease, and pharmacological activation of the proteasome can ameliorate disease phenotypes in preclinical models. Understanding GO:0036402 therefore has broad implications for basic cell biology and therapeutic development.
• Controls ATP-dependent degradation of ubiquitinated proteins, a central hub in protein homeostasis.
• Required for cell-cycle progression and degradation of cell-cycle regulators.
• Heat shock stably activates 26S proteasomes, linking proteasome activation to stress responses.
• Loss of proteasome activation contributes to neuronal phenotypes in FBXO11-deficiency.
• Amyloid-beta impairs proteasome structure and function, and proteasome activation mitigates amyloid-induced toxicity.
• Proteasome-activating peptide 1 attenuates cardiac ischaemia/reperfusion-induced ferroptosis.
• Dual constitutive- and immuno-proteasome inhibitors like TIR-199 impact myeloma-mediated bone degeneration.
• AAA+ protein-based technologies are being developed to counter neurodegenerative disease by modulating proteasome activity.
• Proteasome-activating activity is a potential drug target for cancer and neurodegeneration.
• Archaeal ESCRT-III homolog CdvB degradation is cell-cycle-dependent and proteasome-dependent, highlighting evolutionary conservation.
What Happens During proteasome-activating activity?
ATP Binding and Hydrolysis
In simple terms: The proteasome uses energy from ATP to get ready to destroy proteins.
The AAA+ ATPases of the 19S regulatory particle bind ATP and hydrolyze it to ADP and phosphate. This hydrolysis provides the energy required for subsequent substrate unfolding and channel opening. The reaction is defined as ATP + H2O = ADP + phosphate.
Substrate Unfolding
In simple terms: The proteasome pulls apart the tangled protein so it can fit into the destruction chamber.
After ATP binding, the ATPases unfold the substrate protein, a process that is essential because the 20S core proteasome can only accommodate unfolded polypeptides. This unfolding is coupled to ATP hydrolysis and is a prerequisite for translocation.
Channel Opening of the Core Proteasome
In simple terms: The proteasome opens its gate so the unfolded protein can enter.
The ATPases induce a conformational change that opens the channel of the 20S core proteasome, allowing the unfolded substrate to enter the catalytic chamber. This channel gating activity is a key feature of GO:0036402.
Translocation and Degradation
In simple terms: The protein is threaded into the proteasome and chopped into pieces.
Once the channel is open, the unfolded substrate is translocated into the 20S core, where it is degraded into short peptides. This step is tightly coupled to ATP hydrolysis and is required for the positive regulation of proteasomal protein catabolic process.
Regulation by Heat Shock and Stress
In simple terms: Stress can turn up the proteasome's activity to clear damaged proteins.
Heat shock stably activates 26S proteasomes, leading to increased ubiquitination and protein degradation. This indicates that proteasome-activating activity is dynamically regulated in response to cellular stress.
Key Genes Involved in GO:0036402 proteasome-activating activity
The following genes and proteins are central to proteasome-activating activity, based on verified literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| PSMC1 | AAA+ ATPase of the 19S regulatory particle | Essential for ATP-dependent substrate unfolding and channel opening. |
| PSMC2 | AAA+ ATPase of the 19S regulatory particle | Required for proteasome activation and protein degradation. |
| PSMC3 | AAA+ ATPase of the 19S regulatory particle | Involved in substrate translocation into the 20S core. |
| PSMC4 | AAA+ ATPase of the 19S regulatory particle | Contributes to ATP hydrolysis and channel gating. |
| PSMC5 | AAA+ ATPase of the 19S regulatory particle | Critical for unfolding and degradation of ubiquitinated proteins. |
| PSMC6 | AAA+ ATPase of the 19S regulatory particle | Participates in ATP-dependent proteolysis. |
| PSMD1 | Non-ATPase subunit of the 19S regulatory particle | Scaffolds the ATPase ring and regulates proteasome activity. |
| PSMD2 | Non-ATPase subunit of the 19S regulatory particle | Involved in substrate recognition and proteasome activation. |
| FBXO11 | Substrate receptor for ubiquitination | Deficiency leads to neuronal phenotypes ameliorated by proteasomal activation. |
| CDV B | Archaeal ESCRT-III homolog | Cell-cycle-dependent proteasomal degradation in Sulfolobus. |
| TIR-199 | Syrbactin-class dual proteasome inhibitor | Impedes myeloma-mediated bone degeneration in vivo. |
| β5i | Immunoproteasome subunit | Target of proteasome-activating peptide 1 in cardiac ferroptosis. |
| p53 | Tumor suppressor and transcription factor | Mediates effects of proteasome-activating peptide 1 in ferroptosis. |
| SLC7A11 | Cystine/glutamate antiporter | Downstream of β5i-p53 axis in ferroptosis. |
| Amyloid-beta | Peptide implicated in Alzheimer's disease | Impairs proteasome structure and function. |
| 26S proteasome | Main proteolytic machinery | Stably activated upon heat shock. |
| 19S regulatory particle | Regulatory complex of the 26S proteasome | Contains the AAA+ ATPases that execute GO:0036402. |
How Is proteasome-activating activity Regulated?
Proteasome-activating activity is regulated at multiple levels. Heat shock stably activates 26S proteasomes, increasing ubiquitination and protein degradation. In archaea, the degradation of ESCRT-III homolog CdvB is cell-cycle-dependent, indicating temporal regulation of proteasome activity. Additionally, pharmacological agents such as proteasome-activating peptide 1 can modulate this activity to attenuate ferroptosis through the β5i-p53-SLC7A11 axis. These examples highlight that GO:0036402 is not constitutive but subject to stress, cell-cycle and pharmacological regulation.
proteasome-activating activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| FBXO11 | Neurodevelopmental phenotypes | FBXO11 knockout neurons treated with proteasome activators |
| β5i | Cardiac ferroptosis | Cardiac ischaemia/reperfusion model with proteasome-activating peptide 1 |
| Amyloid-beta | Alzheimer's disease | Amyloid-beta treated neurons and cognitive tests |
| TIR-199 target | Multiple myeloma bone degeneration | Myeloma xenograft model treated with TIR-199 |
| PSMC1-6 | Protein aggregation disorders | Knockout or knockdown of ATPase subunits in cell and animal models |
Neurodegeneration
Proteasome-activating activity is impaired in neurodegenerative conditions. Amyloid-beta impairs proteasome structure and function, and proteasome activation mitigates amyloid-induced toxicity and cognitive deficits. FBXO11-deficiency leads to neuronal phenotypes that are ameliorated by proteasomal activation. These findings suggest that boosting proteasome-activating activity could be therapeutic in Alzheimer's disease and related disorders.
Cardiac Ischaemia/Reperfusion Injury
Proteasome-activating peptide 1 attenuates cardiac ischaemia/reperfusion-induced ferroptosis through the β5i-p53-SLC7A11 axis. This indicates that proteasome activation can protect the heart from ferroptotic cell death during reperfusion injury.
Cancer
Proteasome activity is critical for cancer cell survival and proliferation. Dual constitutive- and immuno-proteasome inhibitor TIR-199 impedes myeloma-mediated bone degeneration in vivo. Targeting proteasome-activating activity may therefore be beneficial in hematological malignancies.
Protein Aggregation Disorders
Defects in proteasome-activating activity contribute to the accumulation of toxic protein aggregates, a hallmark of many neurodegenerative diseases. AAA+ protein-based technologies are being developed to counter these disorders by enhancing proteasome function.
From proteasome-activating activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of PSMC1 affect proteasome activation? | PSMC1 knockout cell line |
| Does a point mutation in the ATPase domain alter channel gating? | Point-mutation knock-in of PSMC2 |
| Can tagged PSMC3 be used to monitor proteasome assembly? | Tagged knock-in of PSMC3 |
| Does overexpression of PSMC4 enhance degradation? | PSMC4 overexpression cell line |
| Does proteasome activation rescue FBXO11-deficiency? | FBXO11 knockout neurons treated with proteasome activators |
| Does proteasome activation mitigate amyloid toxicity? | Amyloid-beta treated neurons with proteasome activators |
How to Study the proteasome-activating activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| ATPase activity assay | ATP hydrolysis rate | Screening for proteasome activators/inhibitors |
| Proteomics | Global protein degradation | Assessing proteasome activation upon heat shock |
| Ubiquitination immunoblot | Ubiquitin conjugate levels | Confirming increased degradation |
| Fluorescence microscopy | Proteasome localization and channel gating | Live-cell imaging of tagged subunits |
| CRISPR knockout screen | Gene essentiality for proteasome activity | Identifying regulators of GO:0036402 |
| RNA-seq | Transcriptional changes | Evaluating cellular response to proteasome modulation |
| Bioinformatics pathway analysis | Enriched pathways and networks | Interpreting CRISPR screen data |
| Animal models | In vivo efficacy of proteasome activators | Testing neuroprotection or cardioprotection |
Proteomics and Degradation Assays
Mass spectrometry-based proteomics can quantify global changes in protein degradation upon modulation of proteasome-activating activity. Ubiquitination levels can be assessed by immunoblotting to confirm increased degradation.
ATPase Activity Assays
ATP hydrolysis can be measured using colorimetric or luminescent assays to directly assess proteasome-activating ATPase activity. These assays are useful for screening small-molecule activators or inhibitors.
Imaging and Subcellular Localization
Fluorescence microscopy with tagged proteasome subunits can visualize channel opening and substrate translocation in live cells. This approach helps determine whether mutations affect proteasome assembly or gating.
Genetic Screens and CRISPR Libraries
CRISPR knockout libraries can identify genes that regulate proteasome-activating activity. Bioinformatics analysis of screening data can reveal pathways and networks involved in proteasome function.
How CRISPR Can Be Used to Study GO:0036402 proteasome-activating activity
Knockout
CRISPR knockout of genes encoding AAA+ ATPases (e.g., PSMC1-6) can abolish proteasome-activating activity, leading to accumulation of ubiquitinated proteins and cell death. Knockout models are useful to study the essentiality of these genes in disease contexts.
Point Mutation
Point mutations in the ATPase domain of PSMC subunits can dissect the contribution of ATP hydrolysis to substrate unfolding versus channel gating. Such models help distinguish between partial and complete loss of function.
Knock-in
Knock-in of tagged versions of proteasome subunits (e.g., GFP-PSMC3) allows real-time monitoring of proteasome assembly and activity in live cells. This is valuable for studying dynamic regulation by heat shock or cell-cycle signals.
Overexpression
Overexpression of proteasome-activating subunits or activators can enhance degradation of toxic proteins and rescue disease phenotypes, as shown for proteasome activation in neurodegeneration and cardiac injury. Overexpression models are used to test therapeutic potential.
How EDITGENE Supports proteasome-activating activity Research
Researchers studying proteasome-activating activity-related genes often need to determine whether a candidate gene is causally involved in proteasome function, substrate degradation or disease phenotypes. EDITGENE provides a comprehensive suite of CRISPR services to generate precisely engineered cell models for such investigations.
Contact EDITGENE today to design your custom CRISPR model for proteasome-activating activity research.
Frequently Asked Questions About proteasome-activating activity
What is GO:0036402 proteasome-activating activity?
GO:0036402 is a molecular function defined as ATP hydrolysis coupled to protein substrate unfolding and opening of the core proteasome channel.
What genes are involved in proteasome-activating activity?
Key genes include PSMC1-6, which encode AAA+ ATPases of the 19S regulatory particle, as well as PSMD1 and PSMD2.
How is proteasome-activating activity regulated?
It is regulated by heat shock, cell-cycle signals and pharmacological agents such as proteasome-activating peptide 1.
What diseases are linked to proteasome-activating activity?
Neurodegeneration, cardiac ischaemia/reperfusion injury and cancer are linked to altered proteasome activation.
What methods are used to study proteasome-activating activity?
ATPase assays, proteomics, ubiquitination immunoblots, fluorescence microscopy and CRISPR screens are commonly used.
Can proteasome activation be therapeutic?
Preclinical studies show that proteasome activation mitigates amyloid toxicity and cardiac ferroptosis, suggesting therapeutic potential.
What is the role of PSMC subunits in proteasome-activating activity?
PSMC subunits form the AAA+ ATPase ring that hydrolyzes ATP, unfolds substrates and opens the 20S channel.
How does heat shock affect proteasome-activating activity?
Heat shock stably activates 26S proteasomes, leading to increased ubiquitination and protein degradation.
What is the connection between FBXO11 and proteasome activation?
FBXO11-deficiency causes neuronal phenotypes that are ameliorated by proteasomal activation.
How can CRISPR be used to study proteasome-activating activity?
CRISPR knockout, point mutation, knock-in and overexpression models allow precise dissection of gene function in proteasome activation.
Conclusion
GO:0036402 proteasome-activating activity is a fundamental molecular function that couples ATP hydrolysis to substrate unfolding and core proteasome channel opening. Its dysregulation is implicated in neurodegeneration, cardiac injury and cancer, and pharmacological activation shows therapeutic promise. CRISPR-based models and advanced proteomics are essential tools to further dissect its mechanism and regulation. EDITGENE offers comprehensive services to support such research.
References
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- 2. Dahlmann B. 2007. Role of proteasomes in disease.. BMC Biochem 8 Suppl 1(Suppl 1):S3 PMID: 18047740
- 3. Gregor A et al.. 2025. Proteasomal activation ameliorates neuronal phenotypes linked to FBXO11-deficiency.. HGG Adv 6(2):100425 PMID: 40114442
- 4. March ZM et al.. 2019. AAA+ Protein-Based Technologies to Counter Neurodegenerative Disease.. Biophys J 116(8):1380-1385 PMID: 30952364
- 5. Lee D et al.. 2022. 26S proteasomes become stably activated upon heat shock when ubiquitination and protein degradation increase.. Proc Natl Acad Sci U S A 119(25):e2122482119 PMID: 35704754
- 6. Kuo YW et al.. 2026. The mechanism of cell-cycle-dependent proteasomal degradation of archaeal ESCRT-III homolog CdvB in Sulfolobus.. EMBO J 45(4):1214-1228 PMID: 41514146
- 7. Davidson K et al.. 2025. β-Amyloid impairs Proteasome structure and function. Proteasome activation mitigates amyloid induced toxicity and cognitive deficits.. bioRxiv PMID: 39484574
- 8. Tandon V et al.. 2022. Syrbactin-class dual constitutive- and immuno-proteasome inhibitor TIR-199 impedes myeloma-mediated bone degeneration in vivo.. Biosci Rep 42(2) PMID: 35088066
