Acetyl-JUN (K271) Antibody

What is Acetyl-JUN (K271) Antibody and what does it specifically detect?

Acetyl-JUN (K271) Antibody is a rabbit polyclonal antibody that specifically recognizes the transcription factor c-Jun (AP-1) only when acetylated at lysine 271. This antibody has been developed using a synthesized peptide derived from the internal region of human AP-1 surrounding the acetylation site of K271 . The antibody detects endogenous levels of AP-1 protein exclusively when acetylation is present at the K271 position . This specificity makes it a valuable tool for studying post-translational modifications of c-Jun and their effects on transcriptional regulation.

The antibody has been affinity-purified from rabbit antiserum using epitope-specific immunogen chromatography, ensuring high specificity for the acetylated form of c-Jun . It does not cross-react with non-acetylated c-Jun, making it an ideal reagent for investigating the acetylation status of this important transcription factor.

What are the validated applications for Acetyl-JUN (K271) Antibody?

Acetyl-JUN (K271) Antibody has been validated for the following research applications:

For optimal results in Western blot applications, researchers should determine the appropriate concentration empirically, as the optimal dilution may vary depending on sample type and experimental conditions . The antibody is supplied at a concentration of 1 mg/ml in PBS containing 50% glycerol, 0.5% BSA, and 0.02% sodium azide .

What species reactivity has been confirmed for this antibody?

The Acetyl-JUN (K271) Antibody has been confirmed to react with acetylated c-Jun from the following species:

• Human

• Mouse

• Rat

This cross-species reactivity has been validated through various experimental applications including Western blot and ELISA . The broad species reactivity makes this antibody valuable for comparative studies across different model organisms. Researchers should note that while reactivity to these three species has been confirmed, other species have not been extensively tested and may require validation before use .

What is the biological significance of c-Jun acetylation at K271?

Acetylation of c-Jun at K271 plays a crucial role in regulating its transcriptional activity. Research has demonstrated that:

• K271 acetylation is essential for the transactivation activity of c-Jun .

• Mutation of the K271 acetylation site and flanking lysine residues results in blockage of c-Jun's transactivational activity even in stimulated conditions .

• The acetylation status at K271 influences c-Jun's ability to regulate expression of downstream target genes including VEGF, c-MET, cyclin D1, and MMP-2 .

Studies have shown that c-Jun acetylation mediates critical cellular processes including angiogenesis and tumor cell survival . The c-Jun protein, when acetylated at K271, shows enhanced DNA binding and transcriptional activation capabilities, making this post-translational modification an important regulatory mechanism in c-Jun-dependent signaling pathways .

How does K271 acetylation affect c-Jun interactions with other transcriptional regulators?

The acetylation of c-Jun at K271 significantly influences its interactions with transcriptional co-regulators and chromatin remodeling factors. Research has revealed that:

Acetylation at K271 promotes c-Jun interaction with the acetyltransferase p300 and other chromatin modifiers . In particular:

• Acetylated c-Jun (K271) forms a complex with Astrocyte Elevated Gene 1 (AEG-1) and p300, which was identified as a novel interaction pathway .

• This tripartite complex enhances chromatin remodeling and increases the accessibility of c-Jun target gene promoters .

• When K271 acetylation is blocked through mutation (K3R-c-Jun mutant), the stimulatory effect of AEG-1 on c-Jun transactivation is drastically diminished .

Expression of the acetylation-deficient c-Jun mutant (K3R) results in smaller tumor formation, reduced angiogenesis (measured by CD31 staining), and decreased cell proliferation (measured by Ki67 staining) compared to wild-type c-Jun . These findings demonstrate that K271 acetylation serves as a molecular switch that modulates c-Jun's ability to recruit transcriptional co-activators and chromatin remodelers, thereby regulating gene expression networks involved in cancer progression.

What are the best practices for validating Acetyl-JUN (K271) Antibody specificity?

To ensure the reliable detection of acetylated c-Jun (K271), researchers should employ the following validation approaches:

• Competition ELISA assay:

  • Coat microtiter plates with random acetyl-lysine peptide-KLH conjugate

  • Test the ability of lysine acetylated and unacetylated peptides to inhibit antibody binding

  • Use antisera at 1:2000 dilution with 2-hour incubation at room temperature

  • Apply secondary goat anti-rabbit antibody at 1:1000 dilution with 1-hour incubation

• Dot blot validation:

  • Test antibody against both non-acetylated peptide library and acetylated peptide library

  • Include positive controls such as lysate from EX527-treated cells (SIRT1 inhibitor increases acetylation)

  • Compare signal intensity between acetylated and non-acetylated samples

• Mutant validation:

  • Use acetylation-deficient mutants (K3R-c-Jun) as negative controls

  • Compare signal between wild-type and mutant samples to confirm specificity

The antibody should detect endogenous levels of c-Jun only when acetylated at K271, with minimal cross-reactivity to non-acetylated forms. Proper validation ensures experimental rigor and reproducibility in acetylation-specific studies.

How can Acetyl-JUN (K271) Antibody be used to study the relationship between c-Jun acetylation and cancer progression?

Acetyl-JUN (K271) Antibody provides a powerful tool for investigating the role of c-Jun acetylation in cancer development and progression through several methodological approaches:

• Correlation analysis in clinical samples:

  • Quantify levels of acetylated c-Jun (K271) in tumor tissues using immunohistochemistry or Western blot

  • Correlate with angiogenesis markers (CD31), proliferation indices (Ki67), and expression of c-Jun downstream genes (VEGF, c-MET, cyclin D1, MMP-2)

  • Statistical analysis has shown significant correlation between AEG-1 expression, acetylated c-Jun levels, and these markers (P < 0.001)

• Functional studies using acetylation-deficient mutants:

  • Compare tumors formed by cells expressing wild-type c-Jun versus acetylation-deficient K3R-c-Jun mutant

  • Measure differences in tumor size, angiogenesis, and proliferation

  • Studies have demonstrated that tumors formed by cells expressing K3R-c-Jun mutant exhibit smaller size and reduced CD31 and Ki67 staining

• Transcriptional activity assessment:

  • Use Electrophoretic Mobility Shift Assay (EMSA) to determine c-Jun DNA binding activity in relation to acetylation status

  • Research has demonstrated strong association between AEG-1 expression and c-Jun transcriptional activity (r = 0.762, P = 0.028)

These methodologies can reveal how c-Jun acetylation at K271 influences cancer-related processes such as angiogenesis, cell survival, and invasion, potentially identifying new therapeutic targets that modulate this post-translational modification.

What experimental controls should be included when using Acetyl-JUN (K271) Antibody in chromatin immunoprecipitation studies?

When performing chromatin immunoprecipitation (ChIP) studies using Acetyl-JUN (K271) Antibody, the following controls are essential to ensure reliable and interpretable results:

• Input control:

  • Reserve a small portion (5-10%) of chromatin before immunoprecipitation

  • Use as reference for enrichment calculations and to control for differences in starting material

• Negative controls:

  • IgG control: Perform parallel immunoprecipitation with non-specific IgG of the same species (rabbit)

  • Non-acetylated region control: Amplify genomic regions not expected to bind c-Jun

  • Acetylation inhibitor treatment: Compare samples treated with acetyltransferase inhibitors

• Positive controls:

  • Known c-Jun target gene promoters (e.g., VEGF, c-MET, cyclin D1, MMP-2)

  • Regions previously validated to bind acetylated c-Jun

• Validation with acetylation-deficient mutants:

  • Perform parallel ChIP experiments in cells expressing K3R-c-Jun mutant

  • Compare enrichment patterns between wild-type and mutant samples

• Sequential ChIP (Re-ChIP):

  • First immunoprecipitate with c-Jun antibody, then with acetyl-K271 antibody (or vice versa)

  • Confirms co-occupancy of acetylated c-Jun at target loci

These controls collectively allow researchers to distinguish between specific signal from acetylated c-Jun (K271) binding and background noise, ensuring the biological validity of ChIP findings when studying c-Jun target gene regulation.

How does c-Jun acetylation at K271 interact with other post-translational modifications?

The acetylation of c-Jun at K271 exists within a complex network of post-translational modifications that collectively regulate c-Jun function. Research has revealed several important interactions:

• Phosphorylation-acetylation crosstalk:

  • c-Jun is known to be phosphorylated by multiple kinases including CaMK4, PRKDC, HIPK3, DYRK2, GSK3B, PAK2, PLK3, and VRK1

  • Phosphorylation at Thr-239, Ser-243, and Ser-249 by GSK3B reduces c-Jun's DNA binding ability

  • The relationship between these phosphorylation events and K271 acetylation remains an active area of investigation

• Ubiquitination-acetylation interplay:

  • c-Jun is ubiquitinated by SCF(FBXW7) following phosphorylation, leading to its degradation

  • Acetylation at K271 may potentially affect recognition by the ubiquitination machinery, influencing protein stability

• Acetylation enzymes:

  • Acetylation at Lys-271 is mediated by the acetyltransferase p300

  • AEG-1 has been identified as a factor that promotes interaction between c-Jun and p300, enhancing acetylation

Understanding these interactions is crucial for comprehending the complete regulatory landscape of c-Jun activity. Researchers investigating these interrelationships should design experiments that can detect multiple modifications simultaneously, such as using antibodies against different modifications in sequential immunoprecipitation experiments or mass spectrometry approaches to map the full complement of c-Jun modifications.

What are common troubleshooting issues when using Acetyl-JUN (K271) Antibody in Western blots?

When using Acetyl-JUN (K271) Antibody in Western blot applications, researchers may encounter several challenges. Here are common issues and their solutions:

• Weak or no signal:

  • Problem: Insufficient antibody concentration or low levels of acetylated protein

  • Solution: Optimize antibody dilution (try 1:500 instead of 1:2000)

  • Solution: Enrich for nuclear proteins in your sample preparation

  • Solution: Treat cells with deacetylase inhibitors (e.g., EX527, a SIRT1 inhibitor) to increase acetylation levels

• High background:

  • Problem: Non-specific binding or excessive antibody concentration

  • Solution: Increase blocking time/concentration and optimize antibody dilution

  • Solution: Use more stringent washing steps with higher salt concentration

  • Solution: Pre-absorb antibody with non-acetylated peptide library

• Cross-reactivity with non-acetylated c-Jun:

  • Problem: Antibody binding to non-acetylated protein

  • Solution: Verify antibody specificity using dot blot with acetylated and non-acetylated peptides

  • Solution: Include K3R-c-Jun mutant samples as negative controls

• Inconsistent results between experiments:

  • Problem: Variation in acetylation levels due to cell culture conditions

  • Solution: Standardize cell culture conditions and treatment times

  • Solution: Include positive controls with known acetylation status

Following the recommended protocol with 1:500-1:2000 dilution for Western blot applications and proper sample preparation techniques should yield reliable and reproducible results .

How should researchers prepare samples to maximize detection of acetylated c-Jun?

To optimize detection of acetylated c-Jun (K271) in experimental samples, researchers should follow these methodological guidelines:

• Cell/tissue lysis optimization:

  • Use nuclear extraction protocols to enrich for nuclear proteins

  • Include protease inhibitors AND deacetylase inhibitors in lysis buffers

  • Maintain cold temperatures throughout sample preparation to minimize deacetylation

• Acetylation preservation strategies:

  • Treat cells with deacetylase inhibitors (such as trichostatin A for HDAC inhibition or EX527 for SIRT1 inhibition) prior to lysis

  • Add 5-10 mM nicotinamide and 1-5 μM trichostatin A to all buffers

  • Process samples quickly to minimize loss of acetylation

• Sample conditions that enhance c-Jun acetylation:

  • Stimulate cells with growth factors or stress conditions known to enhance c-Jun activation

  • Co-express AEG-1, which has been shown to promote c-Jun acetylation through p300 interaction

  • Overexpress p300 acetyltransferase to increase acetylation levels

• Protein handling for Western blot:

  • Avoid excessive freeze-thaw cycles of protein samples

  • Use freshly prepared samples when possible

  • If acetylation signal is weak, consider using immunoprecipitation to concentrate the protein of interest before Western blotting

By incorporating these methodological considerations, researchers can significantly improve the detection of acetylated c-Jun (K271) in their experimental systems, leading to more robust and reproducible results.

What quantification methods are most appropriate for measuring c-Jun acetylation levels?

For accurate quantification of c-Jun acetylation levels, researchers should consider these methodological approaches:

• Western blot quantification:

  • Use densitometry software to measure band intensity

  • Normalize acetylated c-Jun signal to:
    a) Total c-Jun protein (using a pan-c-Jun antibody)
    b) Loading controls such as histone H3 for nuclear proteins

  • Generate standard curves using recombinant acetylated proteins if absolute quantification is required

  • Include multiple biological replicates (n≥3) for statistical validity

• ELISA-based quantification:

  • Develop sandwich ELISA using pan-c-Jun antibody for capture and Acetyl-JUN (K271) Antibody for detection

  • Follow recommended dilution of 1:10000 for ELISA applications

  • Include competition controls with acetylated and non-acetylated peptides

  • Create standard curves using synthetic acetylated peptides

• Mass spectrometry approaches:

  • Enrich for acetylated peptides using the Acetyl-JUN (K271) Antibody

  • Analyze using liquid chromatography-tandem mass spectrometry (LC-MS/MS)

  • Compare acetylated peptide abundance across samples using label-free or isotope labeling methods

  • This approach can simultaneously detect multiple post-translational modifications

• Image-based quantification:

  • For immunofluorescence or immunohistochemistry applications

  • Use specialized software to measure nuclear signal intensity

  • Normalize to total c-Jun staining in parallel sections

  • Perform co-localization analysis with transcriptional co-activators

Each method offers distinct advantages, and researchers should select the appropriate approach based on their specific experimental questions, available equipment, and required sensitivity.

How might Acetyl-JUN (K271) Antibody be used to explore novel therapeutic approaches for cancer?

The Acetyl-JUN (K271) Antibody offers significant potential for developing new cancer therapeutic strategies through the following research approaches:

These research directions could lead to novel therapeutic approaches that specifically target the acetylation-dependent functions of c-Jun, potentially offering more selective treatment options with fewer side effects than general transcription factor inhibitors.

What are emerging techniques for studying the dynamic regulation of c-Jun acetylation?

Advanced methodologies for investigating the temporal and spatial dynamics of c-Jun acetylation at K271 are evolving rapidly. Promising approaches include:

• Live-cell imaging of acetylation dynamics:

  • Development of acetylation-specific intrabodies derived from Acetyl-JUN (K271) Antibody

  • Fusion with fluorescent proteins to visualize acetylation in real-time

  • FRET-based reporters to detect conformational changes upon acetylation

• Single-cell acetylome analysis:

  • Adaptation of antibody-based enrichment for single-cell proteomics

  • Correlation of acetylation patterns with transcriptional profiles at single-cell resolution

  • Spatial mapping of acetylated c-Jun within tumor microenvironments

• CRISPR-based acetylation site editing:

  • Precise modification of K271 site using base editors

  • Creation of acetylation-mimetic mutations (K→Q)

  • Engineering of conditional acetylation systems

• Proximity-dependent labeling approaches:

  • BioID or APEX2 fusions to map the interactome of acetylated versus non-acetylated c-Jun

  • Identification of readers, writers, and erasers specific to K271 acetylation

  • Temporal mapping of dynamic interaction networks

• Structural biology approaches:

  • Cryo-EM analysis of c-Jun complexes with and without K271 acetylation

  • Hydrogen-deuterium exchange mass spectrometry to detect conformational changes upon acetylation

  • Molecular dynamics simulations to predict functional impacts

These emerging techniques, when used in conjunction with Acetyl-JUN (K271) Antibody as a validation tool, will provide unprecedented insights into the dynamics and functional consequences of c-Jun acetylation in normal physiology and disease states.

How does c-Jun K271 acetylation interact with broader epigenetic regulatory networks?

The interplay between c-Jun K271 acetylation and broader epigenetic networks represents a frontier in understanding transcriptional regulation. Key research areas include:

• Coordinated histone and transcription factor acetylation:

  • Investigation of whether acetylated c-Jun preferentially binds to regions with specific histone acetylation patterns

  • Analysis of whether c-Jun acetylation coincides with or precedes histone acetylation at target promoters

  • Role of acetyltransferases like p300 in coordinating both histone and c-Jun acetylation

• Relationship with chromatin remodeling complexes:

  • Interaction studies between acetylated c-Jun and chromatin remodelers

  • Sequential ChIP experiments to map co-occupancy of acetylated c-Jun with specific chromatin modifiers

  • Functional studies to determine whether c-Jun acetylation is required for recruitment of specific remodeling complexes

• Acetylation-dependent enhancer activation:

  • Genome-wide mapping of acetylated c-Jun binding using ChIP-seq

  • Correlation with enhancer activation markers (H3K27ac, eRNA production)

  • Investigation of long-range chromatin interactions mediated by acetylated c-Jun

• Integration with other epigenetic modifications:

  • Cross-talk between c-Jun acetylation and DNA methylation status at target genes

  • Relationship between acetylated c-Jun binding and repressive histone marks

  • Development of multiplexed approaches to simultaneously map multiple epigenetic modifications

These investigations will reveal how c-Jun acetylation at K271 functions within the broader context of epigenetic regulation, potentially identifying novel regulatory mechanisms and therapeutic targets at the intersection of signaling pathways and epigenetic control.

What are the key considerations for researchers planning to use Acetyl-JUN (K271) Antibody?

Researchers planning studies with Acetyl-JUN (K271) Antibody should consider these critical factors for successful implementation:

• Experimental design considerations:

  • Include appropriate positive and negative controls for antibody validation

  • Consider cell treatment conditions that enhance c-Jun acetylation

  • Incorporate acetylation-deficient mutants (K3R-c-Jun) as controls

  • Design time-course experiments to capture dynamic acetylation changes

• Technical recommendations:

  • Store antibody as recommended at -20°C or -80°C and avoid repeated freeze-thaw cycles

  • Optimize antibody concentration for each application (WB: 1:500-1:2000; ELISA: 1:10000)

  • Include deacetylase inhibitors in sample preparation buffers

  • Consider enrichment methods for low-abundance acetylated proteins

• Complementary approaches:

  • Validate key findings with orthogonal methods (e.g., mass spectrometry)

  • Combine with functional assays to correlate acetylation with biological outcomes

  • Consider using multiple antibodies targeting different epitopes of acetylated c-Jun

• Data interpretation guidelines:

  • Normalize acetylated c-Jun signal to total c-Jun levels

  • Consider the broader context of additional post-translational modifications

  • Correlate acetylation status with transcriptional activity measurements

By addressing these considerations, researchers can maximize the utility of Acetyl-JUN (K271) Antibody in their studies and generate reliable, reproducible results that advance understanding of c-Jun regulation through acetylation.

What emerging research questions could be addressed using Acetyl-JUN (K271) Antibody?

The availability of specific Acetyl-JUN (K271) Antibody enables investigation of several cutting-edge research questions:

• Tissue-specific regulation patterns:

  • How does c-Jun K271 acetylation vary across different tissues and cell types?

  • Are there tissue-specific co-regulators that modulate this acetylation?

  • What is the developmental regulation of c-Jun acetylation during embryogenesis and tissue differentiation?

• Disease-specific alterations:

  • Beyond cancer, how is c-Jun K271 acetylation altered in inflammatory, neurodegenerative, or metabolic diseases?

  • Can acetylated c-Jun serve as a biomarker for disease progression or treatment response?

  • Are there disease-specific mutations that affect c-Jun acetylation or its functional consequences?

• Environmental and metabolic influences:

  • How do environmental stressors affect c-Jun acetylation patterns?

  • What is the relationship between cellular metabolism and c-Jun acetylation?

  • How does the availability of acetyl-CoA as a metabolic intermediate influence c-Jun acetylation?

• Non-canonical functions:

  • Does acetylated c-Jun have functions beyond transcriptional regulation?

  • Are there cytoplasmic roles for acetylated c-Jun that differ from its nuclear functions?

  • Does acetylation affect c-Jun's interaction with non-transcriptional partners?

• Therapeutic targeting:

  • Can specific modulation of c-Jun K271 acetylation be achieved pharmaceutically?

  • Would targeting this modification offer therapeutic advantages over broader c-Jun inhibition?

  • What patient populations might benefit from therapies targeting c-Jun acetylation?