JUN (Ab-93) Antibody

What is JUN (Ab-93) Antibody and what epitope does it specifically recognize?

JUN (Ab-93) Antibody is a rabbit polyclonal antibody that specifically targets the amino acid sequence around positions 91-95 (T-P-T-P-T) derived from human c-Jun protein. The antibody is generated by immunizing rabbits with a synthetic peptide and KLH conjugates, followed by purification through affinity chromatography using epitope-specific peptide . This antibody recognizes endogenous levels of total c-Jun protein and is distinct from phospho-specific antibodies that recognize modifications at Thr93 .

The specificity for this particular epitope makes it valuable for detecting total c-Jun protein regardless of its phosphorylation state at nearby residues. The c-Jun protein (encoded by the JUN gene) is a critical component of the AP-1 transcription factor complex and plays essential roles in various cellular processes including proliferation, differentiation, and apoptosis .

What are the validated applications for JUN (Ab-93) Antibody?

JUN (Ab-93) Antibody has been validated for multiple experimental applications:

The antibody shows robust detection of c-Jun in Western blotting applications, with c-Jun typically appearing at approximately 43-48 kDa. For immunohistochemistry, it has been successfully used on formalin-fixed, paraffin-embedded (FFPE) tissue sections with appropriate antigen retrieval .

What is the confirmed species reactivity profile for this antibody?

The antibody demonstrates cross-reactivity with multiple species:

• Human (primary validation)

• Mouse (confirmed reactivity)

• Rat (confirmed reactivity)

This multi-species reactivity is particularly valuable for comparative studies across different model systems. The antibody has been specifically validated using HeLa and HT29 cell extracts for Western blotting applications, and human breast carcinoma tissue for immunohistochemistry .

What are the optimal sample preparation protocols for Western blotting with JUN (Ab-93) Antibody?

For optimal Western blotting results with JUN (Ab-93) Antibody:

• Lysate Preparation:

  • Extract proteins using RIPA buffer supplemented with protease inhibitors

  • Include phosphatase inhibitors if studying c-Jun in the context of phosphorylation signaling

  • For nuclear transcription factors like c-Jun, nuclear extraction protocols often yield cleaner results

• Protein Loading and Separation:

  • Load 20-40 μg of total protein per lane

  • Use 10-12% SDS-PAGE gels for optimal separation around the 43 kDa range

  • Include positive control lysates (e.g., HeLa cells) that are known to express c-Jun

• Transfer and Detection:

  • Use PVDF membranes for optimal protein binding

  • Block with 5% non-fat milk or BSA in TBST

  • Incubate with primary antibody (1:500-1:1000) overnight at 4°C

  • Wash thoroughly and detect with appropriate secondary antibody and chemiluminescence reagents

When interpreting results, note that c-Jun often appears as multiple bands between 43-48 kDa due to various post-translational modifications, particularly phosphorylation states .

What are the critical considerations for immunohistochemistry applications?

For successful immunohistochemical detection using JUN (Ab-93) Antibody:

• Tissue Preparation:

  • Use 4-5 μm sections of formalin-fixed, paraffin-embedded tissues

  • Perform heat-induced epitope retrieval using citrate buffer (pH 6.0) or EDTA buffer (pH 9.0)

  • Allow sufficient retrieval time (15-20 minutes) as c-Jun is a nuclear protein and may require robust antigen retrieval

• Antibody Application:

  • Use the antibody at 1:50-1:200 dilution

  • Incubate overnight at 4°C or for 60 minutes at room temperature

  • Include appropriate blocking steps to minimize background staining

• Detection and Controls:

  • Use HRP-conjugated secondary antibodies and DAB detection systems

  • Include positive control tissues (e.g., human breast carcinoma) known to express c-Jun

  • Include negative controls by omitting primary antibody

The expected staining pattern is predominantly nuclear, consistent with c-Jun's function as a transcription factor .

How should the antibody be stored to maintain optimal activity?

For maximum stability and activity retention:

• Upon receipt, store the antibody at -20°C for long-term preservation

• For frequent use, small working aliquots can be kept at 4°C for up to 2 weeks

• Avoid repeated freeze-thaw cycles as they can degrade antibody performance

• The antibody is typically supplied in a stabilizing buffer (phosphate buffered saline, pH 7.4, 150mM NaCl, 0.02% sodium azide and 50% glycerol) that helps maintain activity

Most manufacturers confirm stability for at least 12 months from the date of receipt when stored properly at -20°C .

Why might multiple bands be observed in Western blots with JUN (Ab-93) Antibody?

Multiple bands when using JUN (Ab-93) Antibody may occur for several legitimate biological and technical reasons:

• Post-translational modifications: c-Jun undergoes extensive phosphorylation, particularly at sites including Thr93, which can cause mobility shifts in SDS-PAGE

• Protein isoforms: Alternative splicing of the JUN gene can generate different protein variants

• Proteolytic degradation: c-Jun is subject to regulated proteolysis, and sample preparation conditions may affect the presence of degradation products

• Cross-reactivity with related proteins: The antibody may recognize other Jun family proteins (JunB, JunD) that share sequence homology, though this is less likely with epitope-specific antibodies

To determine if additional bands represent specific c-Jun forms:

• Compare with other validated c-Jun antibodies targeting different epitopes

• Perform peptide competition assays to confirm specificity

• Use c-Jun knockdown or knockout samples as negative controls

What strategies can improve signal-to-noise ratio in immunodetection experiments?

To optimize signal-to-noise ratio when using JUN (Ab-93) Antibody:

For Western Blotting:

• Increase blocking time (1-2 hours) with 5% BSA or milk in TBST

• Optimize primary antibody concentration through titration experiments

• Increase washing duration and number of washes (at least 3 x 10 minutes with TBST)

• Use freshly prepared buffers and reagents

• Consider specialized blocking reagents for problematic samples

For Immunohistochemistry:

• Increase blocking time with serum-based blockers

• Optimize antigen retrieval conditions

• Use signal amplification systems for low-abundance targets

• Consider implementing tyramide signal amplification for enhanced sensitivity

• Apply appropriate quenching of endogenous peroxidase activity

• Use Avidin/Biotin blocking for tissues with high endogenous biotin

These optimization strategies can significantly improve the specificity and sensitivity of c-Jun detection in various experimental contexts.

How can JUN (Ab-93) Antibody be integrated with phospho-specific antibodies to study c-Jun signaling dynamics?

To comprehensively study c-Jun signaling dynamics:

• Parallel detection approach:

  • Use JUN (Ab-93) Antibody to detect total c-Jun protein levels

  • In parallel, use phospho-specific antibodies (such as phospho-c-Jun (Thr93)) to detect activated forms

  • Calculate the ratio of phosphorylated to total protein to normalize for expression differences

• Sequential immunodetection:

  • Perform immunoblotting with phospho-specific antibody first

  • Strip and re-probe the same membrane with JUN (Ab-93) Antibody

  • This approach allows direct comparison using the same protein samples

• Multiplexed immunofluorescence:

  • Combine JUN (Ab-93) Antibody with phospho-specific antibodies raised in different host species

  • Use spectrally distinct secondary antibodies for simultaneous detection

  • Analyze co-localization to determine cellular distribution of activated c-Jun

This integrated approach provides insights into both c-Jun expression levels and activation states, essential for understanding its role in cellular responses to various stimuli and stress conditions .

What methodological considerations are important for studying c-Jun in the context of the AP-1 transcription complex?

For investigating c-Jun as part of the AP-1 complex:

• Co-immunoprecipitation studies:

  • Use JUN (Ab-93) Antibody to pull down c-Jun and associated proteins

  • Analyze co-precipitated proteins (e.g., c-Fos, ATF family members) by immunoblotting

  • Confirm complex formation under different cellular conditions

• Chromatin Immunoprecipitation (ChIP):

  • Use JUN (Ab-93) Antibody to immunoprecipitate c-Jun-bound chromatin fragments

  • Perform PCR or sequencing to identify DNA binding sites

  • Include appropriate controls to confirm specificity of binding

  • Optimization of formaldehyde cross-linking is critical for nuclear transcription factors

• Mobility shift assays:

  • Use JUN (Ab-93) Antibody in supershift experiments with nuclear extracts and labeled AP-1 consensus oligonucleotides

  • Compare binding patterns with and without antibody to confirm c-Jun involvement in specific complexes

The use of JUN (Ab-93) Antibody in these contexts helps elucidate the composition and function of AP-1 complexes in different cellular contexts and in response to various stimuli .

How can JUN (Ab-93) Antibody be used to investigate c-Jun's role in affinity-matured therapeutic antibody development?

This advanced application connects to emerging therapeutic antibody development strategies:

• Study of affinity maturation mechanisms:

  • Use JUN (Ab-93) Antibody to monitor c-Jun expression and activation in antibody-producing cells

  • Investigate c-Jun's role in transcriptional regulation during somatic hypermutation and affinity maturation

  • Correlate c-Jun activity with antibody affinity improvement metrics

• Analysis of therapeutic antibody properties:

  • As demonstrated in search result , affinity-matured antibodies can exhibit enhanced therapeutic properties

  • JUN (Ab-93) Antibody can be used to study signaling pathways triggered by therapeutic antibody binding

  • Monitor how therapeutic antibodies modulate c-Jun expression and phosphorylation in target cells

• Experimental design approach:

  • Compare c-Jun expression and activation patterns between normal antibody-producing cells and those undergoing affinity maturation

  • Use pharmacological inhibitors of c-Jun pathways to assess their impact on antibody affinity maturation

  • Implement genetic approaches (siRNA, CRISPR) to modulate c-Jun levels and study effects on antibody production and affinity

This approach connects fundamental c-Jun biology with applied therapeutic antibody development, an area highlighted by research showing how affinity-matured antibodies can exhibit improved neutralization properties and reduced adverse effects such as antibody-dependent enhancement (ADE) .

How does the detection sensitivity of JUN (Ab-93) Antibody compare with antibodies targeting other regions of c-Jun?

Comparative sensitivity analysis based on epitope targeting:

• Epitope accessibility differences:

  • JUN (Ab-93) Antibody targets amino acids 91-95, a region that may have different accessibility than C-terminal or N-terminal epitopes

  • Antibodies targeting the DNA-binding domain may have reduced accessibility in chromatin-bound c-Jun

  • Terminal-targeting antibodies may be affected by protein-protein interactions

• Post-translational interference:

  • The Ab-93 region (T-P-T-P-T) contains threonine residues that can be phosphorylated

  • While JUN (Ab-93) Antibody detects total c-Jun regardless of phosphorylation state, its binding efficiency may be subtly affected by modifications at nearby residues

  • This differs from antibodies targeting regions without modification sites

• Sensitivity comparison:

  • Direct comparison studies show that JUN (Ab-93) Antibody exhibits robust detection at dilutions of 1:500-1:1000 for Western blotting

  • When compared with recombinant monoclonal antibodies like EP693Y (targeting a different epitope), comparable sensitivity is observed, though the polyclonal nature of JUN (Ab-93) may provide broader epitope recognition

These comparative considerations help researchers select the optimal antibody based on their specific experimental requirements and the biological context of their study.

What quantitative analysis approaches are recommended when using JUN (Ab-93) Antibody for expression level studies?

For reliable quantification of c-Jun expression:

• Western blot densitometry:

  • Use total protein normalization approaches rather than single housekeeping proteins

  • Apply stain-free technology or Ponceau staining to normalize for loading variations

  • Include standard curves with recombinant c-Jun protein for absolute quantification

  • Use digital image analysis software with appropriate background correction

• Immunohistochemistry quantification:

  • Apply H-score methodology (staining intensity × percentage of positive cells)

  • Use digital pathology approaches for unbiased quantification

  • Implement multiplex staining to normalize c-Jun expression to cell type-specific markers

  • Include calibration controls in each experimental run

• Statistical analysis recommendations:

  • For Western blot data: Perform multiple independent experiments (n≥3)

  • For IHC data: Analyze multiple fields per sample (≥5 fields)

  • Apply appropriate statistical tests based on data distribution

  • Report both fold-changes and absolute values when possible

These quantitative approaches enhance the reliability and reproducibility of c-Jun expression data and facilitate meaningful comparisons across experimental conditions and between studies .

How can researchers integrate data from JUN (Ab-93) Antibody with modern multi-omics approaches?

Integration of antibody-based detection with multi-omics strategies:

• Correlation with transcriptomics:

  • Compare protein levels detected by JUN (Ab-93) Antibody with JUN mRNA expression from RNA-Seq or qPCR

  • Identify potential post-transcriptional regulation mechanisms when discrepancies exist

  • Use time-course studies to determine temporal relationships between mRNA and protein expression

• Integration with phosphoproteomics:

  • Combine JUN (Ab-93) Antibody data with mass spectrometry-based phosphoproteomics

  • Map identified phosphorylation sites to functional domains of c-Jun

  • Correlate c-Jun expression levels with activation of upstream kinases

• Chromatin studies integration:

  • Correlate c-Jun protein levels with ChIP-Seq data to assess relationship between expression and genomic binding

  • Integrate with ATAC-Seq to examine accessibility of c-Jun binding sites

  • Combine with Hi-C or other chromatin conformation techniques to understand 3D genomic context of c-Jun action

This integrative approach provides a comprehensive understanding of c-Jun biology across multiple molecular levels, offering insights that would not be apparent from antibody-based detection alone .