Role: Essential for sperm formation and function, likely via ER-associated degradation (ERAD) pathways .
Interaction: Binds UBE2J1 (an E2 ubiquitin-conjugating enzyme) to regulate protein quality control during spermatogenesis .
T Cell Tolerance:
While no direct studies on RNF133 antibodies exist, hypothetical uses can be extrapolated:
Antibody Development: No published protocols for RNF133 antibody generation exist. Lessons could be drawn from PROTABs targeting related E3 ligases (e.g., RNF43/ZNRF3) .
Functional Redundancy: RNF133 and RNF148 share overlapping roles in spermatogenesis, necessitating dual targeting for contraceptive efficacy .
Safety: Systemic inhibition might risk autoimmune side effects due to RNF133’s immune regulatory role .
Knockout Phenotype: RNF133-deficient mice show sperm defects but retain fertility, suggesting compensatory mechanisms .
Expression Window: Peaks during late meiosis (day 15 in mice), coinciding with spermatid elongation .
Autoimmunity Onset: RNF133 KO mice develop IgG/IgG1 autoantibodies by 12 weeks and overt autoimmune symptoms by 5–6 months .
Mechanistic Insight: RNF133 ubiquitinates unknown substrates to enforce T cell anergy and Treg stability .
Antibody Engineering: Develop bispecific antibodies (like PROTABs ) to degrade RNF133 or its partners.
Functional Studies: Identify RNF133 substrates via yeast two-hybrid screens or proteomic approaches .
Preclinical Models: Test antibody efficacy in spermatogenesis arrest or EAE (autoimmune encephalitis) models .
RNF133 (Ring Finger Protein 133) is an E3 ubiquitin-protein ligase localized in the endoplasmic reticulum. In humans, the canonical protein has 376 amino acid residues with a molecular mass of approximately 42.3 kDa. RNF133 functions primarily in the ubiquitination pathway, targeting specific proteins for degradation via the proteasome system. This post-translational modification mechanism is crucial for protein quality control and cellular homeostasis .
The protein contains a RING finger domain characteristic of many E3 ubiquitin ligases, enabling it to facilitate the transfer of ubiquitin from an E2 ubiquitin-conjugating enzyme to specific substrate proteins. RNF133 is also known by synonyms including E3 ubiquitin-protein ligase RNF133 and RING-type E3 ubiquitin transferase RNF133 .
RNF133 antibodies are employed in various immunodetection techniques to study the expression, localization, and function of RNF133 protein. The most frequently used applications include:
Western Blot (WB): For detecting RNF133 protein in cell or tissue lysates, providing information about protein expression levels and molecular weight.
Enzyme-Linked Immunosorbent Assay (ELISA): For quantitative measurement of RNF133 protein in biological samples.
Immunohistochemistry (IHC): For visualizing RNF133 distribution in tissue sections, providing spatial information about protein localization .
Cytometric Bead Array: For multiplexed protein detection in solution-based assays .
When designing experiments, researchers should carefully select antibodies validated for their specific application and species of interest, as reactivity can vary significantly between products.
Recent research has uncovered significant roles for RNF133 in immune regulation, particularly in T cell function and tolerance. RNF133 shows high expression in tolerant T cells, suggesting it works alongside other molecules like GRAIL to establish and maintain T cell tolerance .
Experimental evidence from knockout models demonstrates that RNF133-deficient CD4+ T cells exhibit enhanced proliferation and cytokine production (particularly IL-17 and IL-21) when activated under tolerogenic conditions. This indicates RNF133's role in controlling T helper cell responses, specifically TH17 and T follicular helper (Tfh) cell responses .
RNF133 expression in regulatory T cells (Tregs) is essential for maintaining their suppressive function and stability, preventing them from acquiring pathogenic TH17 phenotypes. RNF133 knockout mice develop elevated levels of IgG and IgG1 in sera and increased percentages of TH17 and Tfh cells in peripheral lymphoid tissues, eventually leading to autoimmune symptoms by 5-6 months of age .
These findings position RNF133 as a potential checkpoint molecule in maintaining immunological tolerance and preventing inflammatory conditions, making it an important target for immunological research.
When selecting an RNF133 antibody for your research, several critical factors must be evaluated:
Application compatibility: Verify the antibody has been validated for your specific application (WB, IHC, ELISA, etc.). For example, antibody ABIN2034033 has been validated for both Western blot and Immunohistochemistry applications .
Epitope recognition: Consider which region of RNF133 the antibody recognizes. Some antibodies target specific domains or regions that may be masked in certain experimental conditions. For instance, ABIN2034033 recognizes a region within amino acids 23-348 of RNF133 .
Clonality:
Host species: Consider compatibility with your experimental system to avoid cross-reactivity. Document available antibodies are produced in mouse or rabbit hosts .
Species reactivity: Ensure the antibody recognizes RNF133 from your species of interest. Available antibodies show reactivity to human RNF133, while some also cross-react with mouse, rabbit, rat, and horse proteins .
Validation data: Review provided validation data (Western blots, IHC images) to confirm the antibody detects RNF133 with expected molecular weight and tissue distribution patterns.
Storage and handling requirements: Note specific requirements such as storage at -80°C for certain products or avoiding sodium azide for antibodies used with HRP detection systems .
Optimizing Western blot detection of RNF133 requires careful attention to several experimental parameters:
Sample preparation:
Use appropriate lysis buffers containing protease inhibitors to prevent RNF133 degradation
For membrane-associated proteins like RNF133 (localized to ER), include detergents suitable for membrane protein extraction
Optimize protein loading (typically 20-50 μg total protein per lane)
Gel selection and transfer:
Use 10-12% SDS-PAGE gels for optimal resolution of the 42.3 kDa RNF133 protein
Consider wet transfer for more efficient transfer of membrane proteins
Use PVDF membranes for better protein binding and signal-to-noise ratio
Blocking and antibody incubation:
Detection optimization:
Controls:
Include positive control (tissue/cells known to express RNF133)
Use RNF133 knockout or knockdown samples as negative controls when available
Consider loading controls (GAPDH, β-actin) but be aware their expression may not directly correlate with membrane proteins
Troubleshooting:
If multiple bands appear, optimize antibody concentration and washing steps
If signal is weak, consider longer exposure times or signal enhancement systems
For high background, increase washing duration and detergent concentration
Investigating RNF133's role in T cell tolerance requires strategic experimental approaches combining antibody-based detection with functional assays:
Expression profiling across T cell populations:
Use flow cytometry with RNF133 antibodies to quantify expression levels in different T cell subsets (naïve, effector, memory, regulatory)
Compare RNF133 expression in tolerant versus activated T cells using Western blot or immunofluorescence
Correlate expression with tolerance markers and activation status
Subcellular localization studies:
Employ confocal microscopy with RNF133 antibodies alongside ER markers to confirm localization
Investigate whether localization changes during T cell activation or tolerance induction
Use cell fractionation followed by Western blot to biochemically confirm localization patterns
Functional assays with genetic manipulation:
Protein interaction studies:
Use co-immunoprecipitation with RNF133 antibodies to identify binding partners
Confirm interactions with known tolerance mediators (e.g., GRAIL)
Identify ubiquitination targets using RNF133 antibodies to pull down complexes
In vivo tolerance models:
When designing these experiments, it's crucial to include appropriate controls and validate antibody specificity in the context of each application.
Post-translational modifications (PTMs) of RNF133, particularly ubiquitination, present significant challenges for antibody detection. These modifications can alter epitope accessibility, protein conformation, and migration patterns in analytical techniques. Researchers should consider the following strategies:
Epitope masking issues:
Migration pattern variations:
Ubiquitinated RNF133 will appear at higher molecular weights
Use gradient gels (4-15%) to resolve both modified and unmodified forms
Consider native gel electrophoresis to preserve protein complexes and modifications
Enrichment techniques:
Use deubiquitinating enzyme inhibitors in lysates to preserve ubiquitinated forms
Apply ubiquitin-specific pull-down followed by RNF133 antibody detection
Consider phosphatase treatment to eliminate phosphorylation that might affect antibody binding
Strategic antibody selection:
Choose antibodies raised against recombinant proteins with defined modification states
Consider using antibodies specifically designed to detect modified forms of RNF133
Validate antibody performance with both native and denatured protein samples
Data interpretation considerations:
Document all bands observed, not just those at the expected molecular weight
Compare patterns across different experimental conditions known to alter PTM status
Use mass spectrometry as a complementary approach to confirm modifications
When different RNF133 antibodies yield contradictory results, a systematic troubleshooting approach is essential:
Epitope mapping comparison:
Validation with knockout/knockdown controls:
Generate RNF133-deficient samples through CRISPR/Cas9 or siRNA approaches
Test all antibodies against these negative controls to establish specificity
Quantify signal-to-noise ratios for each antibody in identical samples
Cross-platform validation:
Compare results across multiple techniques (WB, IHC, flow cytometry)
Use orthogonal methods not dependent on antibodies (mRNA expression, mass spectrometry)
Correlate findings with functional outcomes in knockout/overexpression systems
Isoform and variant analysis:
Investigate whether contradictory results stem from detection of different RNF133 isoforms
Sequence the target region in your experimental system to confirm conservation
Design isoform-specific detection strategies if necessary
Technical optimization matrix:
Systematically vary experimental conditions (fixation methods, blocking agents, antibody concentration)
Document conditions under which results converge or diverge
Establish optimal protocols for each antibody and application
Independent laboratory validation:
Have experiments repeated by independent researchers or laboratories
Compare findings with published literature on RNF133 detection
Consider antibody validation services or collaborative studies for difficult cases
Multiplexed approaches using RNF133 antibodies can provide comprehensive insights into immune signaling networks:
Cytometric bead array applications:
Utilize validated RNF133 antibody pairs (e.g., MP50868-1) in cytometric bead arrays
Combine with detection of cytokines (IL-17, IL-21) and other signaling molecules
Quantify relationships between RNF133 expression and downstream immune mediators
Working range: 0.098-100 ng/mL for optimal detection sensitivity
Multi-parameter flow cytometry:
Design panels including RNF133 alongside T cell subset markers (CD4, CD25, FOXP3)
Use different fluorochromes for each parameter to avoid spectral overlap
Analyze co-expression patterns in various activation and tolerance states
Consider intracellular staining protocols optimized for nuclear and ER-localized proteins
Multiplexed imaging approaches:
Apply multiplexed immunofluorescence with RNF133 antibodies and other immune markers
Use sequential staining protocols to overcome host species limitations
Employ cyclic immunofluorescence or mass cytometry imaging for higher parameter counts
Analyze spatial relationships between RNF133-expressing cells and other immune populations
Protein-protein interaction networks:
Combine proximity ligation assays with RNF133 antibodies to visualize interactions
Apply FRET/BRET approaches for living cell interaction studies
Use multiplexed co-immunoprecipitation followed by mass spectrometry to identify interaction networks
Map the dynamic changes in these networks during T cell activation versus tolerance induction
Single-cell analysis integration:
Correlate RNF133 protein expression (by antibody detection) with single-cell transcriptomics
Develop computational approaches to integrate protein and mRNA data
Identify cell populations with coordinated expression of tolerance-associated molecules
Non-specific binding represents a significant challenge when working with RNF133 antibodies. Researchers can address this issue through several strategies:
Blocking optimization:
Test different blocking agents (BSA, normal serum, commercial blockers)
Increase blocking time (1-2 hours at room temperature)
Add 0.1-0.3% Triton X-100 to blocking buffer for improved penetration
Consider using the host species serum matching the secondary antibody
Antibody dilution optimization:
Perform titration experiments to identify optimal antibody concentration
Start with manufacturer's recommended dilution and test 2-fold dilution series
Balance signal strength against background for optimal signal-to-noise ratio
For polyclonal antibodies like ABIN2034033, higher dilutions may reduce non-specific binding
Cross-reactivity minimization:
Pre-absorb antibodies with lysates from species prone to cross-reactivity
Include additional blocking steps with irrelevant proteins
Use monoclonal antibodies for higher specificity when possible
Consider fragment antibodies (Fab, F(ab')2) to reduce Fc-mediated binding
Washing protocol optimization:
Increase number and duration of washing steps
Use higher detergent concentrations in wash buffers (0.1-0.5% Tween-20)
Include salt (up to 500 mM NaCl) in wash buffers to reduce ionic interactions
Use agitation during washing to improve efficiency
Secondary antibody considerations:
Use highly cross-adsorbed secondary antibodies
Include secondary-only controls in all experiments
Consider direct conjugation of primary antibodies to eliminate secondary antibody issues
Match secondary antibody class-specificity to primary antibody isotype (e.g., anti-IgG1 for mouse IgG1 primaries )
Proper storage and handling are crucial for maintaining antibody performance:
Storage temperature requirements:
Aliquoting recommendations:
Prepare small volume aliquots (10-50 μL) based on typical experimental needs
Use sterile tubes with secure seals to prevent contamination and evaporation
Document preparation date, concentration, and number of freeze-thaw cycles on each tube
Consider adding carrier protein (BSA) to dilute antibodies for improved stability
Working solution handling:
Contamination prevention:
Use sterile technique when handling antibody stocks
Include antimicrobial agents in working solutions if they will be stored (except sodium azide with HRP)
Filter solutions if visible precipitation occurs
Centrifuge antibody stocks briefly before opening to collect liquid at the bottom
Stability monitoring:
Include positive controls in each experiment to monitor antibody performance over time
Document lot numbers and performance characteristics for each antibody
Consider validation experiments for aged antibodies before using in critical experiments
Maintain storage equipment with backup power and temperature monitoring
Thorough validation of RNF133 antibodies requires a comprehensive set of controls:
Positive expression controls:
Tissues/cells with confirmed RNF133 expression (based on literature or preliminary data)
Recombinant RNF133 protein as a standard for size verification
Overexpression systems with tagged RNF133 that can be detected by alternative methods
Known expression patterns across tissues for immunohistochemistry validation
Negative controls:
RNF133 knockout or knockdown samples
Tissues known not to express RNF133
Pre-absorption of antibody with immunizing peptide/protein
Secondary antibody only controls to assess non-specific binding
Specificity controls:
Western blot demonstration of single band at expected molecular weight (42.3 kDa)
Comparison with orthogonal detection methods (mRNA expression, mass spectrometry)
Cross-validation with multiple antibodies recognizing different epitopes
Peptide competition assays to confirm epitope specificity
Application-specific controls:
Experimental validation:
Demonstration that antibody detects expected biological changes (e.g., upregulation in specific conditions)
Correlation of protein detection with functional outcomes
Reproducibility across multiple experimental replicates
Cross-laboratory validation when possible
Recent research utilizing RNF133 antibodies has revealed important connections between this E3 ubiquitin ligase and autoimmune regulation:
T cell tolerance breakdown mechanisms:
RNF133 knockout models show development of autoimmune symptoms by 5-6 months of age
RNF133 antibodies have helped document elevated levels of IgG and IgG1 in sera and increased TH17 and Tfh cells in peripheral lymphoid tissues of knockout mice
These findings position RNF133 as a potential checkpoint molecule in maintaining immunological tolerance
Regulatory T cell stability:
Antibody-based detection has demonstrated that RNF133 expression in regulatory T cells is essential for their suppressive function and stability
Loss of RNF133 leads to Tregs acquiring pathogenic TH17 phenotypes, contributing to autoimmunity
This finding identifies a previously unknown molecular mechanism for maintaining Treg identity
Comparative analysis with other tolerance mediators:
Despite GRAIL's established role in T cell tolerance, GRAIL knockout mice don't develop early spontaneous autoimmunity
RNF133 shows the highest expression among GRAIL homologs in tolerant T cells
Combined analysis suggests cooperative functions between multiple E3 ligases in maintaining immune homeostasis
Therapeutic target identification:
Characterization of RNF133's role provides new significant insights that may lead to therapeutic developments for inflammatory diseases
Antibody-based screening could identify compounds that modulate RNF133 activity in autoimmune conditions
RNF133 detection in patient samples might serve as a biomarker for autoimmune predisposition or disease progression
Several technological advances are improving RNF133 antibody development and applications:
Recombinant antibody engineering:
Advanced validation technologies:
CRISPR knockout cell line panels for comprehensive antibody validation
Orthogonal protein detection methods (targeted mass spectrometry) for verification
Automated high-throughput screening of antibody performance across multiple applications
Multiplexed detection systems:
Advanced imaging applications:
Super-resolution microscopy with RNF133 antibodies for detailed subcellular localization
Multi-spectral imaging systems for simultaneous detection of RNF133 and interaction partners
Live-cell imaging with minimally disruptive antibody-based detection systems
Application-specific developments:
Single-cell analytical approaches offer unprecedented insights into RNF133 expression patterns:
Single-cell protein-RNA correlation:
Combining RNF133 antibody detection with single-cell RNA sequencing
Revealing discrepancies between transcript and protein levels indicating post-transcriptional regulation
Identifying rare cell populations with distinctive RNF133 expression patterns
Characterizing regulatory networks associated with different RNF133 expression levels
Spatial single-cell analysis:
Implementing multiplex immunofluorescence with RNF133 antibodies in tissue sections
Mapping spatial relationships between RNF133-expressing cells and other immune populations
Correlating expression patterns with tissue microenvironments in health and disease
Identifying niches supporting tolerogenic versus autoimmune phenotypes
Temporal dynamics at single-cell resolution:
Time-course analyses of RNF133 expression during T cell activation and tolerance induction
Live-cell imaging with antibody-based sensors to track RNF133 dynamics
Correlation of expression changes with functional outcomes in individual cells
Identification of expression thresholds associated with tolerance versus activation
Heterogeneity analysis in immune populations:
Characterizing RNF133 expression variance across T cell subsets (naïve, memory, effector, regulatory)
Identifying potential subpopulations with distinctive RNF133 expression levels
Correlating expression patterns with functional capacities (suppression, cytokine production)
Exploring how RNF133 expression heterogeneity contributes to population-level immune responses
Integrated multi-omic approaches:
Combining antibody-based RNF133 detection with epigenetic profiling at single-cell level
Integrating protein, RNA, and epigenetic data to build comprehensive regulatory networks
Developing predictive models of RNF133 function based on multi-parametric single-cell data
Identifying novel therapeutic targets within the RNF133-associated regulatory network
Selecting between monoclonal and polyclonal RNF133 antibodies involves weighing several considerations:
When designing critical experiments, consider using both types complementarily to leverage their respective strengths while minimizing limitations.
Different platforms offer varying performance characteristics for RNF133 detection:
When selecting a platform, researchers should consider their specific research questions, available sample types, and required data outputs.
Several bioinformatic resources can enhance interpretation of RNF133 antibody-generated data:
Protein interaction databases:
STRING-db: For visualizing known and predicted RNF133 protein interactions
BioGRID: For curated protein-protein interaction data
IntAct: For experimentally verified molecular interactions
These resources help place RNF133 in broader signaling networks and suggest potential functions
Pathway analysis tools:
KEGG Pathway: For mapping RNF133 to known biological pathways
Reactome: For detailed biochemical pathway information
Gene Ontology: For functional classification of RNF133 and related proteins
These tools help interpret the functional significance of RNF133 expression patterns
Expression databases:
Human Protein Atlas: For tissue-specific expression patterns of RNF133
ImmGen: For immune cell-specific expression profiles
Single Cell Portal: For single-cell RNA-seq data including RNF133 expression
These resources provide context for antibody-detected expression patterns
Structure prediction and analysis:
AlphaFold: For RNF133 protein structure prediction
PyMOL: For visualizing antibody epitopes on predicted structures
SWISS-MODEL: For homology modeling of RNF133 domains
Structural information helps interpret antibody binding sites and functional domains
Data integration platforms:
Cytoscape: For network visualization of RNF133 in protein interaction networks
R Bioconductor packages: For statistical analysis of antibody-generated data
Galaxy: For workflow creation and data integration
These platforms help integrate antibody data with other -omics datasets
Specialized immune system databases:
By leveraging these resources, researchers can place their antibody-generated data in broader biological contexts and generate testable hypotheses about RNF133 function.
RNF133 research is rapidly evolving, with several emerging trends that will shape future antibody technology development:
Expanding functional understanding:
Therapeutic targeting:
As RNF133's role as an immunological checkpoint molecule becomes established, therapeutic modulation will gain interest
Antibodies serving as both research tools and potential therapeutics may emerge
Screening platforms using RNF133 antibodies will help identify small molecule modulators
Single-cell and spatial biology integration:
Understanding RNF133's heterogeneous expression across immune cell populations requires advanced detection methods
Antibodies compatible with multiplexed imaging and single-cell protein analysis will become essential
Development of antibodies suitable for non-permeabilized cell detection to maintain spatial relationships
Systems biology approaches:
Placing RNF133 within broader ubiquitination networks requires comprehensive detection tools
Antibodies targeting multiple E3 ligases simultaneously in standardized formats
Development of antibody panels for entire ubiquitination pathways
Technological advancements:
Nanobodies and alternative binding proteins may offer improved tissue penetration and reduced immunogenicity
CRISPR-based epitope tagging systems paired with standardized tag antibodies
Machine learning approaches to predict optimal epitopes for antibody development
These trends will drive the evolution of more specific, sensitive, and versatile RNF133 antibody technologies to meet the growing needs of basic and translational research.
Several critical questions about RNF133 biology remain unanswered:
Substrate identification:
What are the specific protein targets ubiquitinated by RNF133?
Advanced co-immunoprecipitation with RNF133 antibodies followed by mass spectrometry
Proximity labeling approaches using RNF133 antibodies to identify nearby proteins
Development of antibodies recognizing RNF133-substrate complexes
Regulatory mechanisms:
How is RNF133 itself regulated at transcriptional and post-translational levels?
Antibodies recognizing specific post-translational modifications of RNF133
ChIP-seq approaches with antibodies against transcription factors regulating RNF133
Antibody-based detection of RNF133 half-life and turnover rates
Tissue-specific functions:
Does RNF133 play different roles in various tissues and cell types?
Immunohistochemistry with highly specific antibodies across tissue arrays
Single-cell resolution mapping of RNF133 expression in complex tissues
Correlation of tissue-specific expression with local functional outcomes
Disease associations:
Beyond autoimmunity, does RNF133 dysfunction contribute to other pathologies?
Development of clinical-grade antibodies for patient sample analysis
Tissue microarray analysis of RNF133 in various disease states
Correlation of expression patterns with clinical outcomes and disease progression
Therapeutic targeting:
Can modulation of RNF133 activity be therapeutically beneficial in autoimmune diseases?
Antibodies capable of modulating RNF133 activity (agonists/antagonists)
Screening platforms using RNF133 antibodies to identify small molecule modulators
Monitoring tools to assess therapeutic efficacy in preclinical and clinical settings
Advanced antibody applications will be instrumental in addressing these questions, particularly when integrated with complementary technologies like CRISPR-based genetic manipulation, mass spectrometry, and high-resolution imaging.