GO:0061635 regulation of protein complex stability: Mechanism, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0061635 (regulation of protein complex stability) is a biological process that controls the assembly or disassembly of protein complexes, thereby affecting their structure and integrity [1, 4, 5].
• Protein complex stability is often regulated by post-translational modifications such as ubiquitination, which can target subunits for degradation or alter binding interfaces [1, 4, 5].
• E3 ubiquitin ligases, deubiquitinases, and molecular chaperones are key regulators of complex stability in diverse cellular contexts [1, 4, 5, 6].
• Dysregulation of protein complex stability contributes to cancer, neurodegeneration, and developmental disorders [1, 5, 7, 8].
• CRISPR-based knockout, point mutation, knock-in, and overexpression models enable functional dissection of genes controlling complex stability [1, 4, 5, 7, 8].
• Emerging tools such as molecular glues can stabilize native protein-protein interactions, offering therapeutic opportunities.
Description
The Gene Ontology (GO) term GO:0061635, regulation of protein complex stability, describes any process that affects the structure and integrity of a protein complex by altering the likelihood of its assembly or disassembly. This process is fundamental to cellular function because protein complexes carry out essential tasks such as DNA replication, signal transduction, and RNA processing [1, 4, 5]. The stability of these complexes is dynamically controlled in response to developmental cues, stress, and disease states [1, 4, 5]. Understanding how complex stability is regulated provides insight into basic cell biology and identifies potential therapeutic targets [1, 5, 6]. Regulation of protein complex stability often involves post-translational modifications, particularly ubiquitination, which can mark subunits for degradation or modulate their interactions [1, 4, 5]. For example, the deubiquitinase USP35 stabilizes survivin, a chromosomal passenger complex component, by removing degradative ubiquitin chains. Similarly, the E3 ligase Smurf2 targets CNKSR2 for degradation, affecting breast cancer progression. These examples illustrate how the balance between ubiquitination and deubiquitination controls complex integrity [1, 5]. Beyond ubiquitin-dependent mechanisms, molecular glues and chaperones can stabilize protein-protein interactions directly. The U1 snRNP-specific protein U1C is required for SMN complex-mediated snRNP formation, highlighting the role of dedicated assembly factors. Cohesin-mediated stabilization of the CCAN complex at kinetochores ensures proper chromosome segregation during mitosis. Thus, regulation of protein complex stability is a broad and critical process with diverse molecular players [1, 4, 5, 6, 7, 8].
regulation of protein complex stability At A Glance
| GO ID | GO:0061635 |
|---|---|
| GO term | regulation of protein complex stability |
| Ontology | biological_process |
| Synonym | None |
| Major function | Controls assembly or disassembly of protein complexes, affecting their structure and integrity |
| Related processes | Protein ubiquitination, deubiquitination, chaperone-mediated assembly, molecular glue action |
| Key regulators | E3 ubiquitin ligases, deubiquitinases, chaperones, assembly factors |
| Disease relevance | Cancer, neurodegeneration, developmental disorders, asthma |
What Is GO:0061635?
GO:0061635, regulation of protein complex stability, is defined as any process that affects the structure and integrity of a protein complex by altering the likelihood of its assembly or disassembly. In other words, it encompasses all cellular mechanisms that determine whether a protein complex remains intact or is broken down, thereby influencing its abundance and function.
Why Is regulation of protein complex stability Important in Cell Biology?
Regulation of protein complex stability is essential for virtually all cellular processes, as it ensures that multiprotein machines are assembled only when and where needed and are disassembled when their function is complete or when conditions change [1, 4, 5]. Dysregulation of this process can lead to accumulation of aberrant complexes or loss of essential ones, contributing to diseases such as cancer, neurodegeneration, and asthma [1, 3, 5, 7, 8]. Understanding the mechanisms that control complex stability is therefore crucial for both basic biology and therapeutic development [1, 5, 6].
• Controls the availability of functional protein complexes in response to cellular signals [1, 4, 5].
• Regulates cell cycle progression through complexes like survivin and cohesin [1, 8].
• Modulates signal transduction pathways, including MAPK signaling via Cdc42 turnover.
• Impacts RNA processing through SMN complex and snRNP formation.
• Plays a role in cancer progression, as seen with CNKSR2 and survivin [1, 5].
• Involved in asthma through sphingolipid-mediated effects on protein complexes.
• Provides targets for molecular glues that stabilize protein-protein interactions.
• Affects chromosome segregation via CCAN complex stabilization.
• Contributes to neurodegenerative disease mechanisms through SMN complex dysfunction.
• Offers opportunities for CRISPR-based functional genomics and drug discovery [1, 4, 5, 6, 7, 8].
What Happens During regulation of protein complex stability?
Recognition of complex subunits
In simple terms: The cell identifies which protein subunits need to be assembled or removed.
Regulation of protein complex stability begins with the recognition of specific subunits or interaction interfaces. This can involve chaperones that bind to nascent polypeptides or E3 ubiquitin ligases that recognize degrons on target proteins [1, 4, 5]. For example, the HECT E3 ligase Smurf2 recognizes CNKSR2 and targets it for degradation, thereby regulating its stability. Similarly, USP35 recognizes ubiquitinated survivin and removes ubiquitin chains to stabilize it.
Post-translational modification of subunits
In simple terms: Chemical tags are added to or removed from proteins to change their stability.
Ubiquitination is a major post-translational modification that regulates protein complex stability. E3 ligases attach ubiquitin chains to lysine residues on target proteins, often leading to proteasomal degradation [1, 4, 5]. Conversely, deubiquitinases such as USP35 remove these chains, stabilizing the target. Other modifications, such as phosphorylation, can also affect complex assembly or disassembly. The balance between these modifications determines the fate of the complex [1, 4, 5].
Assembly or disassembly of the complex
In simple terms: The modified proteins either come together to form a complex or fall apart.
Once subunits are modified, they may assemble into a functional complex or be targeted for disassembly. Assembly factors such as U1C facilitate the formation of the SMN complex, which is essential for snRNP biogenesis. In contrast, ubiquitination of a subunit can lead to complex disassembly and degradation [1, 5]. Cohesin-mediated stabilization of the CCAN complex at kinetochores exemplifies how assembly is promoted to ensure proper mitosis.
Quality control and degradation
In simple terms: Misfolded or unneeded complexes are destroyed.
Protein complexes that fail to assemble correctly or are no longer needed are often degraded by the proteasome or autophagy. Ubiquitination serves as a signal for degradation, as seen with CNKSR2 and Cdc42 [4, 5]. The m6A RNA modification can also influence the stability of proteins involved in RNA processing, linking RNA modifications to protein complex stability. This quality control ensures that only functional complexes persist [1, 4, 5].
Regulation by molecular glues and chaperones
In simple terms: Helper molecules can glue proteins together or help them fold.
Molecular glues are small molecules that stabilize native protein-protein interactions, as demonstrated with 14-3-3 proteins. Chaperones assist in folding and assembly, preventing aggregation and promoting complex stability. These mechanisms offer therapeutic avenues for stabilizing complexes that are lost in disease.
Key Genes Involved in GO:0061635 regulation of protein complex stability
The following genes and proteins are key players in the regulation of protein complex stability, as supported by published literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| USP35 | Deubiquitinase that stabilizes survivin | Cancer, cell cycle regulation |
| Survivin (BIRC5) | Chromosomal passenger complex component | Mitosis, apoptosis, cancer |
| Cdc42 | Rho GTPase involved in MAPK signaling | Filamentous growth, signal transduction |
| CNKSR2 | Scaffold protein in MAPK pathway | Breast cancer progression |
| Smurf2 | HECT E3 ubiquitin ligase | Targets CNKSR2 for degradation |
| 14-3-3 proteins | Regulatory proteins binding phosphoserine/threonine | Molecular glue targets, signal transduction |
| U1C | U1 snRNP-specific protein | SMN complex-mediated snRNP formation |
| SMN | Survival motor neuron protein | Spinal muscular atrophy, snRNP assembly |
| Cohesin | Ring-shaped complex holding sister chromatids | Chromosome segregation, mitosis |
| CCAN | Constitutive centromere-associated network | Kinetochore assembly, mitosis |
| m6A machinery | RNA methylation writers/erasers/readers | RNA stability, protein complex regulation |
| Sphingolipid enzymes | Sphingolipid metabolism | Asthma, inflammation |
How Is regulation of protein complex stability Regulated?
Regulation of protein complex stability is itself controlled at multiple levels. Ubiquitination and deubiquitination provide reversible switches, with E3 ligases and deubiquitinases acting antagonistically [1, 4, 5]. Phosphorylation can create or destroy binding sites for regulatory proteins such as 14-3-3. RNA modifications like m6A can influence the stability of proteins involved in RNA processing complexes. Additionally, molecular glues can exogenously stabilize protein-protein interactions, offering pharmacological control. These layers of regulation ensure precise spatial and temporal control of complex assembly and disassembly [1, 2, 4, 5, 6].
regulation of protein complex stability and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| USP35 | Cancer (survivin stabilization) | Knockout in cancer cell lines, xenograft models |
| CNKSR2 | Breast cancer progression | Knockout or overexpression in breast cancer cells |
| SMN1 | Spinal muscular atrophy | Knockout in iPSC-derived motor neurons |
| Cohesin subunits | Chromosomal instability, cancer | Knockout in HeLa or RPE1 cells |
| Sphingolipid enzymes | Asthma | Knockout in airway smooth muscle cells |
Cancer
Dysregulation of protein complex stability is a hallmark of cancer. Overexpression of USP35 stabilizes survivin, promoting tumor cell survival and proliferation. Smurf2-mediated degradation of CNKSR2 affects breast cancer progression, with loss of CNKSR2 associated with aggressive phenotypes. Targeting these stability regulators is a promising therapeutic strategy [1, 5].
Neurodegeneration and developmental disorders
Mutations in SMN1 cause spinal muscular atrophy due to impaired SMN complex assembly and snRNP formation, highlighting the importance of complex stability in motor neuron survival. Defects in U1C, a key regulator of SMN complex-mediated snRNP formation, can also contribute to neurodegeneration.
Asthma and inflammatory diseases
Sphingolipids influence protein complex stability in airway smooth muscle and immune cells, contributing to asthma pathogenesis. Modulating sphingolipid metabolism may alter complex stability and inflammatory responses.
Mitotic disorders and chromosomal instability
Cohesin-mediated stabilization of the CCAN complex at kinetochores is essential for mitosis; its disruption leads to chromosomal instability and aneuploidy, common in cancer and developmental disorders.
From regulation of protein complex stability-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does gene X regulate complex stability? | CRISPR knockout cell line followed by proteomics [1, 4, 5] |
| Does a point mutation affect complex assembly? | CRISPR point mutation knock-in [1, 5] |
| Does tagging a subunit affect complex integrity? | CRISPR knock-in of epitope tag [7, 8] |
| Does overexpression stabilize a complex? | CRISPR overexpression (CRISPRa) or cDNA overexpression [1, 5] |
| Which genes regulate complex stability genome-wide? | CRISPR library screening with complex stability reporter [1, 4, 5] |
| Can a molecular glue stabilize a complex? | Cell-based assay with molecular glue treatment |
How to Study the regulation of protein complex stability Process
| Method | What It Measures | Typical Application |
|---|---|---|
| AP-MS | Protein-protein interactions and complex composition | Identifying subunits of a complex [7, 8] |
| Ubiquitination assay | Ubiquitin chain attachment/removal | Determining if a protein is ubiquitinated [1, 4, 5] |
| Proteomics (SILAC/TMT) | Relative protein abundance and stability | Quantifying complex subunit turnover [1, 4, 5] |
| Live-cell imaging | Real-time complex assembly/disassembly | Visualizing dynamics of complex stability [7, 8] |
| CRISPR knockout screen | Genes required for complex stability | Genome-wide discovery of regulators [1, 4, 5] |
| Molecular glue assay | Stabilization of protein-protein interactions | Testing small molecules that enhance complex stability |
| RNA immunoprecipitation | RNA-protein interactions affecting stability | Linking m6A to protein complex stability |
Proteomics and interactomics
Mass spectrometry-based proteomics can identify subunits of protein complexes and quantify their stability after genetic perturbation [1, 4, 5]. Affinity purification coupled to mass spectrometry (AP-MS) reveals interaction partners and complex composition [7, 8].
Ubiquitination assays
In vivo and in vitro ubiquitination assays detect the addition or removal of ubiquitin chains on target proteins, providing direct evidence of regulation [1, 4, 5]. Deubiquitinase activity assays measure the removal of ubiquitin from substrates.
Imaging and live-cell reporters
Fluorescence microscopy with tagged subunits allows real-time visualization of complex assembly and disassembly [7, 8]. FRET or split-fluorescent protein systems can report on complex stability in living cells.
CRISPR screening and functional genomics
Genome-wide CRISPR knockout or activation screens can identify regulators of protein complex stability using reporters or phenotypic readouts [1, 4, 5]. These screens are powerful for discovering novel components [1, 4, 5].
How CRISPR Can Be Used to Study GO:0061635 regulation of protein complex stability
Knockout
CRISPR knockout of a candidate gene can abolish its function and reveal its role in regulating protein complex stability. For example, knocking out USP35 destabilizes survivin, leading to mitotic defects. Similarly, knockout of Smurf2 stabilizes CNKSR2 and affects breast cancer cell phenotypes.
Point Mutation
CRISPR point mutation knock-in can introduce specific amino acid changes to test the importance of post-translational modification sites or interaction interfaces. For instance, mutating ubiquitination sites on a subunit can prevent its degradation and stabilize the complex [1, 5].
Knock-in
CRISPR knock-in of epitope tags or fluorescent proteins allows tracking of endogenous complex subunits and assessment of their stability in real time [7, 8]. This approach preserves native regulation and stoichiometry [7, 8].
Overexpression
CRISPR activation (CRISPRa) or cDNA overexpression can increase the levels of a regulator or subunit, testing whether excess protein stabilizes or disrupts a complex [1, 5]. Overexpression of USP35, for example, increases survivin stability.
How EDITGENE Supports regulation of protein complex stability Research
Researchers studying regulation of protein complex stability-related genes often need to determine whether a candidate gene is causally involved in maintaining or disrupting a specific protein complex. This requires precise genetic models that can knockout, mutate, tag, or overexpress the gene of interest in relevant cell types.
Contact EDITGENE today to design your custom CRISPR model for regulation of protein complex stability research.
Frequently Asked Questions About regulation of protein complex stability
What is GO:0061635?
GO:0061635 is the Gene Ontology term for regulation of protein complex stability, defined as any process that affects the structure and integrity of a protein complex by altering the likelihood of its assembly or disassembly.
What genes are involved in regulation of protein complex stability?
Key genes include USP35, survivin (BIRC5), Cdc42, CNKSR2, Smurf2, U1C, SMN, cohesin subunits, and CCAN components, among others [1, 4, 5, 7, 8].
How is protein complex stability regulated?
It is regulated by post-translational modifications such as ubiquitination and deubiquitination, by chaperones, and by molecular glues that stabilize protein-protein interactions [1, 4, 5, 6].
What diseases are associated with dysregulated protein complex stability?
Cancer, neurodegeneration (e.g., spinal muscular atrophy), asthma, and chromosomal instability disorders are associated with dysregulated complex stability [1, 3, 5, 7, 8].
What methods are used to study regulation of protein complex stability?
Common methods include AP-MS, ubiquitination assays, proteomics, live-cell imaging, and CRISPR screens [1, 4, 5, 6, 7, 8].
How can CRISPR be used to study protein complex stability?
CRISPR knockout, point mutation, knock-in tagging, and overexpression can be used to perturb genes and assess effects on complex assembly and stability [1, 4, 5, 7, 8].
What is the role of USP35 in protein complex stability?
USP35 is a deubiquitinase that stabilizes survivin by removing ubiquitin chains, thereby regulating chromosomal passenger complex stability.
How does Smurf2 regulate CNKSR2 stability?
Smurf2 is an E3 ubiquitin ligase that targets CNKSR2 for ubiquitination and degradation, affecting breast cancer progression.
What is the connection between m6A and protein complex stability?
m6A RNA modification can influence the stability of proteins involved in RNA processing complexes, linking RNA modifications to protein complex regulation.
Can molecular glues stabilize protein complexes?
Yes, molecular glues such as those targeting 14-3-3 proteins can stabilize native protein-protein interactions, offering therapeutic potential.
Conclusion
Regulation of protein complex stability (GO:0061635) is a fundamental biological process that controls the assembly and disassembly of multiprotein machines. Its dysregulation underlies numerous diseases, making it a rich area for research and therapeutic intervention [1, 3, 5, 7, 8]. Advances in CRISPR-based models and molecular glues are providing new tools to dissect and manipulate this process [1, 4, 5, 6, 7, 8].
References
- 1. Wang W et al.. 2021. Regulation of survivin protein stability by USP35 is evolutionarily conserved.. Biochem Biophys Res Commun 574:48-55 PMID: 34438346
- 2. Wei G. 2024. RNA m6A modification, signals for degradation or stabilisation?. Biochem Soc Trans 52(2):707-717 PMID: 38629637
- 3. Worgall TS. 2022. Sphingolipids and Asthma.. Adv Exp Med Biol 1372:145-155 PMID: 35503179
- 4. González B et al.. 2022. Regulation of Cdc42 protein turnover modulates the filamentous growth MAPK pathway.. J Cell Biol 221(12) PMID: 36350310
- 5. David D et al.. 2018. Regulation of CNKSR2 protein stability by the HECT E3 ubiquitin ligase Smurf2, and its role in breast cancer progression.. BMC Cancer 18(1):284 PMID: 29534682
- 6. Konstantinidou M et al.. 2025. Stabilization of Native Protein-Protein Interactions with Molecular Glues: A 14-3-3 Case Study.. Acc Chem Res 58(18):2840-2851 PMID: 40910885
- 7. Ngu DM et al.. 2025. The U1 snRNP-specific protein U1C is a key regulator of SMN complex-mediated snRNP formation.. J Biol Chem 301(9):110514 PMID: 40707003
- 8. Haase J et al.. 2025. Cohesin-mediated stabilization of the CCAN complex at kinetochores in mitosis.. Curr Biol 35(16):3943-3958.e5 PMID: 40730158
