DCAF10 Antibody

What is DCAF10 and what cellular functions has it been implicated in?

DCAF10 (DDB1 and CUL4 Associated Factor 10, also known as WDR32) contains seven WD repeats and functions as a substrate receptor for CUL4-DDB1 E3 ubiquitin-protein ligase complexes . Recent research demonstrates that DCAF10 plays a critical role in protein degradation pathways, particularly in the context of viral infection responses. It has been shown to interact with adenovirus E1A protein, forming part of a ubiquitin ligase complex that targets specific proteins for degradation, including AAA+ ATPases RUVBL1/2, which are subunits of HSP90 co-chaperones required for assembly of cellular protein machines involved in anti-viral defenses .

Which applications are DCAF10 antibodies most commonly validated for?

DCAF10 antibodies have been extensively validated for multiple applications with varying recommended dilutions:

• Western Blotting (WB): 1:100-1:2000 dilution range

• Immunohistochemistry (IHC): 1:20-1:200

• Immunoprecipitation (IP): 1:200-1:1000

• Immunofluorescence (IF): 1:20-1:200

• ELISA: Validated but specific dilutions vary by manufacturer

• Flow Cytometry (FACS): Validated for some antibodies

The optimal application depends on the specific epitope recognized, as antibodies targeting different regions of DCAF10 may perform differently in various techniques .

How should DCAF10 antibodies be stored to maintain optimal activity?

To maintain optimal activity, most DCAF10 antibodies should be stored at -20°C in buffer systems containing stabilizers and preservatives. The typical storage buffer consists of PBS with 0.02% sodium azide and 50% glycerol at pH 7.3 . This formulation helps prevent protein denaturation during freeze-thaw cycles. For long-term storage (up to 12 months), manufacturers recommend avoiding repeated freeze-thaw cycles . For short-term use during ongoing experiments, antibodies can be stored at 4°C for approximately one week, but recycling and reuse of antibodies is generally not recommended as buffer systems change after use, potentially compromising antibody performance .

What are the key considerations when designing experiments to study DCAF10-E1A interactions?

When designing experiments to study DCAF10-E1A interactions, researchers should consider:

• Cell line selection: A549 cells (human bronchial carcinoma) and HBTECs (Human Bronchial/Tracheal Epithelial Cells) have been successfully used in published studies .

• Immunoprecipitation conditions: Maintain specific protein-protein interactions by using conditions that preserve complex integrity. Studies have shown that wt e1a forms a complex with DCAF10, but e1a C-terminal mutants do not .

• Controls: Include appropriate controls such as:

  • Mock-infected cells

  • Cells expressing wild-type e1a

  • Cells expressing e1a C-terminal mutants (FOXKb-, DCAF7b-, CtBPb-)

• Detection methods: Use anti-e1a (M58) for immunoprecipitation followed by mass spectrometry or western blotting to detect DCAF10 association .

• Knockdown experiments: Consider DCAF10 siRNA knockdown to evaluate the effect on e1a protein levels, which can confirm the functional relationship between DCAF10 and e1a .

How can researchers effectively validate DCAF10 antibody specificity for their experimental systems?

Validating DCAF10 antibody specificity requires multiple approaches:

• Positive and negative controls: Use cell lines known to express DCAF10 (e.g., A549) as positive controls. For negative controls, implement DCAF10 knockdown via siRNA to verify signal reduction .

• Western blot analysis: Confirm the detected protein band matches the expected molecular weight of DCAF10 (approximately 61 kDa) .

• Immunogen competition assay: Pre-incubate the antibody with its specific immunogen peptide to verify signal elimination in subsequent applications.

• Multiple antibody verification: Use antibodies targeting different epitopes of DCAF10 to confirm consistent results .

• Cross-reactivity testing: If working with non-human samples, verify species reactivity as some DCAF10 antibodies react with human, mouse, and rat proteins while others are human-specific .

• Multiple application validation: Confirm target specificity across different techniques (WB, IHC, IP) when possible .

What sample preparation methods optimize DCAF10 detection in different applications?

Optimal sample preparation varies by application:

For Western Blotting:

• Lyse cells in a buffer containing protease inhibitors to prevent degradation

• For A549 cells, researchers have successfully used standard lysis conditions with the recommended loading of 35 μg protein per lane

• Denature samples at 95°C for 5 minutes in reducing sample buffer before loading

For Immunohistochemistry:

• Use formalin-fixed, paraffin-embedded (FFPE) tissue sections

• Perform antigen retrieval methods (typically heat-induced epitope retrieval)

• Optimal dilutions for IHC range from 1:20 to 1:200

• Human thyroid cancer and esophagus cancer tissues have been verified as positive control samples

For Immunoprecipitation:

• Use mild lysis conditions to preserve protein-protein interactions

• For co-immunoprecipitation of DCAF10 complexes, maintain conditions that preserve the ~1 MDa multi-protein complex described in research findings

How does DCAF10 function in the CRL4 E3 ubiquitin ligase complex during adenovirus infection?

DCAF10 functions as a key component in a CRL4 E3 ubiquitin ligase complex during adenovirus infection through several mechanistic steps:

• Complex assembly: Wild-type e1a promotes the assembly of an e1a-DCAF10-containing CRL4 E3 ubiquitin ligase complex. Research shows that while DDB1 associates with DCAF10 regardless of e1a presence, the critical subunits CUL4A or CUL4B only co-immunoprecipitate with DCAF10 in the presence of wild-type e1a .

• Substrate targeting: The e1a-DCAF10-CRL4 complex targets specific proteins for degradation, primarily the AAA+ ATPases RUVBL1/2. These are essential subunits of HSP90 co-chaperones required for quaternary assembly of cellular protein complexes involved in antiviral defense .

• IRF3 regulation: The complex prevents IRF3 stabilization indirectly. By targeting RUVBL1/2 for degradation, it disrupts the assembly of protein machinery required for IRF3 stabilization .

• Counteracting host defenses: This mechanism allows adenovirus to counteract the host's innate immune response activated by e1a's N-terminal interactions, which would otherwise lead to IRF3 stabilization and subsequent activation of interferon-stimulated genes (ISGs) .

• Self-regulation: Interestingly, the e1a-DCAF10-CRL4 complex also targets e1a itself for degradation, as demonstrated by increased e1a stability upon DCAF10 knockdown .

This sophisticated mechanism represents an evolutionary adaptation by adenovirus to evade host antiviral responses by repurposing the host's own protein degradation machinery.

What are the technical challenges in detecting DCAF10 in subcellular fractionation experiments?

Detecting DCAF10 in subcellular fractionation experiments presents several technical challenges:

• Complex formation interference: DCAF10's involvement in a ~1 MDa multi-protein complex can complicate clean separation during fractionation . The complex's size and stability under various buffer conditions may affect fractionation efficiency.

• Dynamic localization: As part of an E3 ubiquitin ligase complex, DCAF10 may exhibit dynamic localization depending on cellular conditions and activation state.

• Low endogenous expression: DCAF10 may be expressed at relatively low levels in some cell types, requiring sensitive detection methods.

• Buffer compatibility: The choice of fractionation buffers can affect antibody recognition. For optimal results, researchers should:

  • Use buffers that maintain protein conformation but allow sufficient extraction

  • Include protease inhibitors to prevent degradation

  • Test different detergent concentrations that maintain epitope accessibility

• Antibody validation: Different DCAF10 antibodies recognize distinct epitopes (N-terminal regions AA 113-142, AA 118-148, etc.) , which may have differential accessibility in various subcellular compartments.

• Cross-reactivity: Some antibodies may cross-react with other WD-repeat containing proteins in certain cellular fractions, necessitating careful validation of specificity in the experimental system.

To overcome these challenges, researchers should optimize fractionation protocols specifically for DCAF10 detection and validate results using multiple antibodies targeting different epitopes.

How can researchers distinguish between DCAF10 isoforms in experimental systems?

Distinguishing between DCAF10 isoforms requires strategic experimental approaches:

• Isoform-specific detection: DCAF10 has at least two isoforms produced by alternative splicing . To distinguish between them:

  • Select antibodies that target regions unique to specific isoforms

  • The major isoform (isoform 1) has a theoretical molecular weight of 61 kDa

  • Use high-resolution SDS-PAGE (8-10%) to separate closely migrating isoforms

• RT-PCR strategies: Design primers that span alternative splice junctions to amplify isoform-specific transcripts. This approach can quantify relative isoform expression at the mRNA level before protein analysis.

• Mass spectrometry: Use targeted proteomics approaches to identify isoform-specific peptides. This can be particularly valuable when antibodies cannot distinguish between closely related isoforms.

• Recombinant expression controls: Express recombinant versions of each isoform as positive controls to validate the migration pattern and antibody reactivity in your experimental system.

• Isoform-specific knockdown: Design siRNAs targeting unique regions of specific isoforms to validate antibody specificity and isoform-specific functions.

• Tissue/cell type considerations: Consider that isoform expression may vary by tissue or cell type, which could impact experimental design and interpretation of results.

What are common pitfalls in DCAF10 co-immunoprecipitation experiments and how can they be addressed?

Common pitfalls in DCAF10 co-immunoprecipitation experiments include:

• Complex disruption: The DCAF10-containing complex is approximately 1 MDa in size , making it susceptible to disruption during experimental procedures.
  Solution: Use gentle lysis conditions (avoid harsh detergents) and maintain appropriate salt concentrations to preserve protein-protein interactions.

• Low signal strength: DCAF10 interactions may be transient or occur in substoichiometric ratios.
  Solution: Consider crosslinking approaches to stabilize interactions before immunoprecipitation, but validate that crosslinking doesn't interfere with antibody recognition.

• Non-specific binding: WD-repeat proteins like DCAF10 can show non-specific interactions in co-IP experiments.
  Solution: Include appropriate negative controls (IgG control, DCAF10 knockdown samples) and use stringent washing conditions without disrupting specific interactions.

• Antibody specificity issues: Some antibodies may recognize epitopes involved in protein-protein interactions.
  Solution: Test multiple antibodies targeting different regions of DCAF10 (e.g., N-terminal regions AA 113-142, AA 118-148) to identify those that don't interfere with complex formation.

• Competition with endogenous proteins: When using overexpressed tagged DCAF10, competition with endogenous protein may occur.
  Solution: Consider knockdown-rescue approaches, replacing endogenous DCAF10 with tagged versions.

• Buffer incompatibility: Buffer components can affect complex stability and antibody performance.
  Solution: Optimize IP buffer conditions based on published successful protocols. For studying DCAF10-e1a interactions, refer to the specific conditions used in published research .

How should researchers interpret contradictory results between DCAF10 antibody detection and genetic knockdown experiments?

When facing contradictory results between antibody detection and genetic knockdown experiments:

• Knockdown efficiency assessment: First verify knockdown efficiency at both mRNA and protein levels. Published studies show that siRNA typically reduces DCAF10 mRNA to ~30-40% of control levels .

• Antibody specificity verification: Determine if the antibody detects non-specific bands or cross-reacts with related proteins by:

  • Comparing observed molecular weight (should be ~61 kDa for DCAF10)

  • Testing the antibody in multiple applications

  • Using multiple antibodies targeting different epitopes

• Temporal considerations: Discrepancies may result from different half-lives of mRNA versus protein. The research shows that DCAF10 knockdown effects on target proteins (like IRF3) can be observed without changes in target mRNA levels .

• Compensatory mechanisms: Consider that genetic knockdown may trigger compensatory upregulation of related proteins with redundant functions.

• Post-translational modifications: Antibodies may have differential sensitivity to post-translationally modified forms of DCAF10, while knockdown affects all forms.

• Complex formation effects: In the context of the DCAF10-CRL4 complex, knockdown may have indirect effects on complex assembly that aren't directly reflected in simple antibody detection assays .

• Controls: Include appropriate controls such as rescue experiments (re-expressing DCAF10 following knockdown) to confirm specificity of observed phenotypes.

What methodological approaches can resolve conflicting data on DCAF10's role in protein stability regulation?

To resolve conflicting data on DCAF10's role in protein stability regulation:

• Combined approaches: Integrate multiple methodologies to build a comprehensive picture:

  • Genetic: Use both siRNA knockdown and CRISPR-Cas9 knockout approaches

  • Pharmacological: Employ proteasome inhibitors (e.g., MG132) and NEDD8-activating enzyme inhibitors (e.g., MLN4924)

  • Biochemical: Conduct in vitro ubiquitination assays with purified components

• Protein half-life measurements: Implement cycloheximide chase assays to directly measure protein stability with and without DCAF10 manipulation.

• Ubiquitination analysis: Directly assess ubiquitination status of putative DCAF10 targets by:

  • Immunoprecipitating the target protein and blotting for ubiquitin

  • Using tandem ubiquitin binding entities (TUBEs) to purify ubiquitinated proteins

  • Mass spectrometry analysis to identify ubiquitination sites

• Structure-function analysis: Generate DCAF10 mutants that specifically disrupt different functions:

  • WD-repeat mutations that affect substrate binding

  • Mutations in regions required for DDB1 interaction

  • Truncation mutants to map functional domains

• Temporal dynamics: Investigate the temporal relationship between DCAF10 activity and target protein degradation using inducible systems.

• Context dependence: Examine DCAF10 function across different cell types, as its activity may vary based on cellular context.

• Substrate validation: For putative targets like RUVBL1/2, validate direct versus indirect effects by reconstituting the degradation system in vitro with purified components .

This systematic approach can help resolve conflicting data by distinguishing direct from indirect effects and identifying context-dependent functions of DCAF10 in protein stability regulation.

How can DCAF10 antibodies be utilized to investigate its role in cellular responses beyond viral infection?

DCAF10 antibodies can be instrumental in exploring roles beyond viral infection through:

• Stress response studies: Investigate DCAF10 localization and complex formation under various cellular stresses:

  • Genotoxic stress (UV, radiation, chemical mutagens)

  • Metabolic stress (nutrient deprivation, hypoxia)

  • Proteotoxic stress (heat shock, proteasome inhibition)

  Research indicates DCAF10 may be involved in responses to genotoxic and metabolic stress through its targeting of RUVBL1/2, which are required for cellular stress responses .

• Cell cycle regulation: Use DCAF10 antibodies in synchronized cell populations to:

  • Track expression and localization changes throughout the cell cycle

  • Identify cell cycle-dependent interaction partners by co-IP

  • Determine if DCAF10-mediated protein degradation varies with cell cycle phase

• Tissue-specific functions: Apply immunohistochemistry with DCAF10 antibodies across normal and disease tissues:

  • Compare expression patterns in different tissues

  • Correlate with tissue-specific CRL4 complex activity

  • Human thyroid cancer and esophagus cancer tissues have been validated for DCAF10 antibody staining

• Non-degradative functions: Investigate potential scaffolding or regulatory roles beyond protein degradation:

  • Chromatin immunoprecipitation (ChIP) to identify potential chromatin association

  • Proximity labeling (BioID, APEX) to map the DCAF10 interaction network

• Conditional knockout models: Combine DCAF10 antibodies with inducible knockout systems to validate antibody specificity and track acute phenotypic changes following DCAF10 depletion.

What methodological innovations could improve detection and functional analysis of endogenous DCAF10 protein complexes?

Methodological innovations to improve DCAF10 complex analysis include:

• Proximity labeling techniques: Implement BioID or APEX2 fusion proteins to identify proximal proteins in living cells, capturing transient or weak interactions that might be lost in traditional co-IP approaches.

• Crosslinking mass spectrometry (XL-MS): Apply this technique to map the architecture of the ~1 MDa DCAF10-containing complex by identifying interaction interfaces between complex components.

• Single-molecule imaging: Develop fluorescent protein fusions or antibody-based detection systems for live-cell imaging of DCAF10 dynamics and complex formation.

• Cryo-electron microscopy: Pursue structural studies of purified DCAF10-containing complexes to understand the molecular basis of substrate recognition and complex assembly.

• Targeted protein degradation tools: Engineer DCAF10-based degraders (e.g., PROTACs) that hijack the CRL4-DCAF10 system to target proteins of interest, providing insights into complex function.

• Nanobody development: Generate DCAF10-specific nanobodies for improved imaging, co-IP, and potential intracellular functional perturbation.

• Gene editing with endogenous tagging: Use CRISPR-Cas9 to introduce small epitope tags into the endogenous DCAF10 locus, allowing detection of physiological complexes without overexpression artifacts.

• DCAF10 interactome mapping: Combine antibody-based purification with quantitative proteomics across different cellular conditions to build a comprehensive interactome map.

How might DCAF10's role in protein degradation be exploited for therapeutic development in viral infections or cancer?

DCAF10's role in protein degradation offers several therapeutic opportunities:

• Viral infection therapies:

  • Small molecule inhibitors of the DCAF10-E1A interaction could restore antiviral responses during adenovirus infection by preventing degradation of RUVBL1/2 and subsequent IRF3 stabilization

  • Peptide mimetics that occupy the DCAF10 binding site on E1A could function as competitive inhibitors

  • Given that other viruses likely employ similar strategies, DCAF10-targeting approaches might have broad antiviral applications

• Cancer therapeutic strategies:

  • DCAF10 expression analysis in cancer tissues (already validated in thyroid and esophagus cancer ) could identify malignancies dependent on DCAF10 function

  • PROTAC (Proteolysis Targeting Chimera) technology could be developed to redirect DCAF10-CRL4 complexes to degrade oncoproteins

  • If DCAF10 proves to be overexpressed or mutated in certain cancers, it could serve as a direct therapeutic target

• Combination therapies:

  • Since DCAF10 regulates IRF3 stability , combining DCAF10 inhibitors with immunotherapies might enhance antitumor immune responses

  • DCAF10 inhibition could potentially sensitize resistant tumors to existing therapies by modulating protein stability networks

• Biomarker development:

  • DCAF10 antibodies could be employed to develop diagnostic or prognostic biomarkers in diseases where DCAF10 function is altered

  • Monitoring DCAF10 complex assembly could serve as a pharmacodynamic marker for related therapeutic interventions

• Drug development platforms:

  • In vitro reconstitution of the DCAF10-CRL4 complex could provide a platform for high-throughput screening of modulators

  • Structure-based drug design targeting the DCAF10-substrate interface could yield highly selective therapeutic agents