The DNAJC12 antibody is a polyclonal rabbit IgG antibody designed for detecting the DNAJC12 protein, a member of the HSP40 family of molecular chaperones. This antibody is widely used in research and diagnostic settings to study DNAJC12’s role in cellular stress responses, protein folding, and disease pathogenesis. Its applications span immunohistochemistry (IHC), western blotting (WB), immunofluorescence (IF), and enzyme-linked immunosorbent assay (ELISA), as validated in multiple studies .
DNAJC12 encodes a 186-amino-acid protein that functions as a cochaperone for HSP70 and HSP90, facilitating the proper folding of client proteins such as phenylalanine hydroxylase (PAH) and tyrosine hydroxylase . Its J-domain interacts with HSP70 to regulate ATPase activity, ensuring protein homeostasis under stress conditions .
The antibody is integral to diagnostic workflows for HPA and DNAJC12 deficiency. It enables detection of protein expression levels in tissues, guiding therapeutic interventions such as sapropterin dihydrochloride administration .
DNAJC12 is a member of the molecular chaperone Hsp40/DnaJ family, which plays a crucial role in protein folding and proteostasis regulation. It functions as a co-chaperone of HSP70, with all members of the HSP40 family possessing one or more J domains . DNAJC12 is predominantly localized in the cytoplasm of cells, where it participates in essential cellular functions related to protein quality control .
The significance of DNAJC12 in research has grown substantially due to its emerging role as a potential biomarker in various cancers. Recent studies have demonstrated that DNAJC12 expression levels correlate with clinical outcomes in several cancer types, including breast, lung, rectal, and gastric cancers . Interestingly, DNAJC12 appears to function differently depending on the tissue context, potentially acting as a tumor suppressor in breast cancer while exhibiting oncogenic properties in other cancer types .
Additionally, DNAJC12 has been shown to bind to Hsc70 and is upregulated in response to endoplasmic reticulum (ER) stress, suggesting its involvement in cellular stress response mechanisms . This multifaceted role makes DNAJC12 an important target for researchers studying cancer biology, protein quality control, and cellular stress responses.
Researchers have access to various types of DNAJC12 antibodies, each with specific characteristics suited for different experimental applications:
Based on host species:
Based on clonality:
Monoclonal antibodies: These offer high specificity for a single epitope, such as the rabbit monoclonal antibody ABIN7266821
Polyclonal antibodies: These recognize multiple epitopes on the DNAJC12 protein, providing potentially higher sensitivity but may have more batch-to-batch variation
Based on target regions:
Specific region antibodies targeting:
Selection criteria for researchers:
Application compatibility: Verify the antibody has been validated for your intended application (Western blot, IHC, ICC, ELISA)
Species reactivity: Ensure the antibody recognizes DNAJC12 in your species of interest (human, mouse, rat, etc.)
Isoform specificity: Consider which DNAJC12 isoform you need to detect (e.g., isoform a is commonly detected in research studies)
Application-specific dilutions: Check recommended dilutions for your application (e.g., 1:500-1:2000 for Western blotting)
Validation data: Review available validation data before purchase, including images of Western blots or IHC staining
When pursuing quantitative analyses or comparing DNAJC12 across multiple samples, consistency in antibody selection is critical for reliable and reproducible results.
DNAJC12 antibodies are utilized across multiple research applications, each offering unique insights into DNAJC12 biology:
Western Blotting (WB):
Allows quantification of DNAJC12 protein expression levels
Can distinguish between different DNAJC12 isoforms
Immunohistochemistry (IHC):
Essential for analyzing DNAJC12 expression in tissue samples
Particularly valuable in cancer research for examining expression in patient tumor samples
Immunocytochemistry (ICC):
Helpful for co-localization experiments with potential interacting partners
Can reveal subcellular distribution patterns
Enzyme-Linked Immunosorbent Assay (ELISA):
Useful for high-throughput screening applications
Immunoprecipitation:
Critical for studying protein-protein interactions involving DNAJC12
Can be combined with mass spectrometry for interactome analysis
These applications collectively provide researchers with a comprehensive toolkit for investigating DNAJC12 expression, localization, interactions, and functions in various biological contexts.
Optimized Western blotting protocols for DNAJC12 detection require attention to several key methodological details:
Sample preparation:
Use lysis buffers containing protease inhibitors to prevent degradation
For DNAJC12 studies, effective lysis can be achieved using 10 mM Tris–HCl (pH 8.0), 1 mM EDTA, 150 mM NaCl, 1% NP-40, and protease inhibitors at 4°C
Process samples quickly and maintain cold temperatures throughout
Protein separation:
Use 10-12% SDS-PAGE gels for optimal resolution of DNAJC12 (approximately 23 kDa)
Load equal amounts of protein (verify with total protein staining or housekeeping controls)
Include molecular weight markers to accurately identify DNAJC12 bands
Transfer and blocking:
Transfer proteins to nitrocellulose membranes using standard techniques
Block membranes with 5% non-fat milk or BSA in TBST to minimize background
Antibody incubation:
Primary antibody: Use anti-DNAJC12 antibodies at dilutions of 1:500 to 1:2000
Incubate primary antibodies overnight at 4°C for optimal binding
Secondary antibody: Use HRP-conjugated secondary antibodies matching the host species of the primary antibody
Detection and analysis:
Visualize using enhanced chemiluminescence detection methods
For quantitative analysis, use digital imaging systems and normalize to loading controls
Be aware that the longer DNAJC12 isoform (isoform a) is commonly detected in research studies
Troubleshooting tips:
High background: Increase blocking time or antibody dilution
No signal: Verify DNAJC12 expression in your sample; consider positive controls
Multiple bands: May represent different DNAJC12 isoforms or post-translational modifications
Non-specific bands: Increase antibody dilution or try a more specific antibody
Including appropriate controls is essential for result interpretation and validation of findings related to DNAJC12 expression.
Effective immunohistochemistry (IHC) with DNAJC12 antibodies requires adherence to these methodological best practices:
Tissue preparation:
Use formalin-fixed, paraffin-embedded (FFPE) tissues or tissue microarrays (TMAs)
TMAs are particularly valuable for high-throughput analysis across multiple samples
Optimal section thickness is typically 4-5 μm
Antigen retrieval:
Critical step for unmasking epitopes hidden by fixation
Heat-induced epitope retrieval in citrate buffer (pH 6.0) or EDTA buffer (pH 9.0)
Optimize time and temperature for your specific DNAJC12 antibody
Blocking and antibody incubation:
Block endogenous peroxidase activity (3% H₂O₂)
Block non-specific binding sites (2-5% normal serum)
Apply primary DNAJC12 antibody at optimized dilution
Incubate at 4°C overnight for best results
Detection and visualization:
Use appropriate detection system (e.g., HRP-polymer and DAB substrate)
Counterstain with hematoxylin to visualize tissue architecture
Dehydrate, clear, and mount with permanent mounting medium
Scoring and analysis:
DNAJC12 protein is predominantly expressed in the cytoplasm of tumor cells
Consider using an H-score system combining staining intensity and percentage of positive cells
For clinical correlations, stratify into high/low expression groups
Quality control measures:
Include positive control tissues known to express DNAJC12
Include negative controls (primary antibody omitted)
Perform batch staining to minimize technical variability
In breast cancer studies, DNAJC12 protein expression detected by IHC has shown significant differences based on ER status (P < .001), tumor size (P = .013), and lymph node status (P = .005) , highlighting the importance of correlating expression with clinicopathological parameters.
Validating antibody specificity is critical for ensuring reliable research results. For DNAJC12 antibodies, researchers should implement these validation approaches:
Western blot validation:
Verify that the antibody detects a band of the expected molecular weight for DNAJC12 (~23 kDa)
Confirm detection of recombinant DNAJC12 protein as a positive control
Compare detection in samples with varying endogenous DNAJC12 expression levels
Perform knockdown experiments (siRNA/shRNA) to demonstrate reduced signal
Peptide competition assay:
Pre-incubate the antibody with excess synthetic peptide (corresponding to the immunogen)
A specific antibody will show diminished or absent signal after peptide competition
Run competed and non-competed antibody samples side-by-side for comparison
Multiple antibody approach:
Use antibodies from different manufacturers or targeting different epitopes
Concordant results across multiple antibodies suggest greater specificity
For example, compare results between antibodies targeting different regions of DNAJC12 (N-terminal, middle region, C-terminal)
Orthogonal validation:
Compare protein expression (by immunoblotting) with mRNA expression (by qRT-PCR)
Correlation between protein and transcript levels supports antibody specificity
This approach was used in breast cancer studies comparing DNAJC12 mRNA and protein expression
Knockout/knockdown validation:
Use CRISPR/Cas9 knockout or siRNA knockdown of DNAJC12
Absence of signal in knockout cells provides strong evidence of specificity
Include wild-type cells as positive controls
Isotype control:
Use non-specific IgG from the same species as the primary antibody
Helps distinguish specific binding from Fc receptor-mediated background
Documentation of these validation steps should be included in research publications to enhance reproducibility and reliability of findings related to DNAJC12 expression and function.
DNAJC12 antibodies enable detailed investigation of this protein's role in ER stress responses through several methodological approaches:
Experimental induction of ER stress:
Treat cells with established ER stress inducers:
Verify ER stress induction by measuring stress markers like BiP/GRP78
Time-course analysis:
Monitor DNAJC12 expression changes at multiple time points after stress induction
Research has shown that A23187 produces an appreciable increase in DNAJC12 levels beginning at 8 hours and peaking around 16-24 hours
Prepare whole-cell extracts at predetermined intervals (e.g., 4, 8, 16, 24, 48 hours)
Expression analysis methods:
Western blotting: Use anti-DNAJC12 antibodies to quantify protein expression changes
Immunofluorescence: Assess potential changes in subcellular localization during stress
qRT-PCR: Complement protein analysis with mRNA expression analysis
Isoform-specific analysis:
Determine which DNAJC12 isoforms respond to ER stress
Previous research showed that isoform a was specifically upregulated during ER stress
Use antibodies that can distinguish between isoforms when possible
Mechanistic investigations:
Co-immunoprecipitation with anti-DNAJC12 antibodies to identify stress-induced interactions
Combined with mass spectrometry for comprehensive interactome analysis
Investigate interactions with other chaperones (e.g., Hsc70)
Functional studies:
siRNA knockdown of DNAJC12 followed by ER stress induction
Assess impact on cellular viability, UPR signaling, and protein aggregation
Overexpression studies to determine if DNAJC12 can protect against ER stress
This methodological framework allows researchers to comprehensively characterize DNAJC12's dynamic regulation and functional significance during ER stress, providing insights into cellular proteostasis mechanisms.
DNAJC12 has emerged as a potential prognostic biomarker in cancer research, particularly for breast cancer. Researchers can implement the following methodological approach:
Expression analysis methods:
Protein-level analysis:
mRNA-level analysis:
qRT-PCR for targeted expression analysis
RNA-seq or microarray data from public repositories
Correlation with clinicopathological parameters:
Analyze DNAJC12 expression in relation to:
Survival analysis techniques:
Data presentation:
*For HER2+ patients, low DNAJC12 was associated with poor RFS, while high DNAJC12 was related to poor OS
Treatment response prediction:
Analyze DNAJC12 expression in treatment responders vs. non-responders
In breast cancer, tumors of non-responder patients presented lower DNAJC12 expression for:
Multivariate models:
Adjust for established prognostic factors
When adjusted for ER status and TNM staging, lower DNAJC12 expression remained associated with worse prognosis (P = .006)
These methodological approaches allow researchers to robustly evaluate DNAJC12's potential as a prognostic and predictive biomarker across different cancer types and subtypes.
Investigating DNAJC12 protein-protein interactions is crucial for understanding its biological functions. Researchers can employ these methodological approaches:
Co-immunoprecipitation (Co-IP):
Express tagged versions of DNAJC12 (e.g., HA-tagged DNAJC12)
Lyse cells using appropriate buffers (e.g., 10 mM Tris–HCl pH 8.0, 1 mM EDTA, 150 mM NaCl, 1% NP-40 with protease inhibitors)
Immunoprecipitate using:
Wash, elute (e.g., with urea), and analyze bound proteins by immunoblotting
Previous research has demonstrated DNAJC12 interaction with Hsc70 using this approach
Mass spectrometry-based interactome analysis:
Perform immunoprecipitation of DNAJC12 as described above
Process samples for mass spectrometry analysis:
Subject to short SDS-PAGE and stain with colloidal blue
Excise gel bands and perform trypsin digestion
Analyze by LC-MS/MS
Use appropriate controls (IgG immunoprecipitation, untagged controls)
Apply bioinformatics tools to identify significant interactors
Immunofluorescence co-localization:
Co-express potential interacting partners (e.g., FLAG-tagged proteins)
Fix cells in formalin solution and perform immunostaining:
Visualize using confocal microscopy to assess co-localization
Quantify co-localization using Pearson's correlation coefficient or other metrics
Proximity ligation assay (PLA):
Enables visualization of protein interactions (<40 nm proximity) in situ
Apply primary antibodies against DNAJC12 and potential interacting partners
Add PLA probes with attached oligonucleotides
If proteins are in close proximity, oligonucleotides can be ligated and amplified
Detect fluorescent signal indicates protein-protein interaction
Bimolecular Fluorescence Complementation (BiFC):
Fuse DNAJC12 to one half of a split fluorescent protein (e.g., YFP-N)
Fuse candidate interacting proteins to complementary half (e.g., YFP-C)
Co-express in cells - interaction brings fragments together, reconstituting fluorescence
Live-cell imaging can detect and localize interactions
These complementary approaches provide researchers with a comprehensive toolkit to investigate DNAJC12's interactome, particularly its association with chaperone networks and stress response pathways.
Interpreting DNAJC12 expression patterns across cancer types requires careful consideration of context-dependent functions and methodological approaches:
Tissue-dependent roles:
DNAJC12 exhibits dual functions depending on cancer type:
This dichotomy suggests tissue-specific molecular contexts influence DNAJC12 function
Molecular subtype stratification:
Within breast cancer alone, DNAJC12's prognostic significance varies by subtype:
Researchers should avoid generalizing across all cancer types or even subtypes within a cancer type
Expression level assessment:
Consider both:
Absolute expression levels (how much DNAJC12 is expressed)
Relative changes (how expression differs from normal tissue)
Different baseline expression levels across tissues may explain varying functional impacts
Mechanistic context:
In lung cancer, DNAJC12 promotes tumor growth through:
Different signaling networks and interacting partners across tissues may explain opposing roles
Methodological considerations:
Compare studies using similar detection methods (IHC vs. mRNA analysis)
Confirm findings across multiple cohorts and datasets
Be aware of antibody specificity for different DNAJC12 isoforms
Consider scoring methods when comparing across studies
Research interpretation example:
"Our findings indicate that DNAJC12 functions as a tumor suppressor in breast cancer, contrasting with its reported oncogenic role in lung, rectal, and gastric cancers. These seemingly contradictory roles likely reflect tissue-specific molecular contexts and interaction networks. Further mechanistic studies investigating DNAJC12's protein partners and pathway involvement in each cancer type are needed to elucidate the molecular basis for these divergent functions."
This nuanced interpretation approach acknowledges cancer heterogeneity and highlights the importance of context-specific analysis when studying DNAJC12's role in cancer biology.
Robust statistical analysis of DNAJC12 expression data requires appropriate methodologies tailored to research questions:
Comparative analyses:
For categorical variables (e.g., tumor grade, receptor status):
For continuous variables:
Survival analyses:
Expression cutoff determination:
Median-based approach: Divide samples into high/low based on median expression
ROC curve analysis: Determine optimal threshold maximizing sensitivity/specificity
Quartile-based approach: Compare highest vs. lowest expression quartiles
Treatment response prediction:
Calculate area under curve (AUC) to quantify discriminatory ability:
Consider sensitivity, specificity, positive and negative predictive values
Statistical reporting standards:
State statistical methods clearly in publications
Report exact P-values rather than thresholds (e.g., P = .006 rather than P < .01)
Document software packages used for analysis
Consider multiple testing corrections for genome-wide or proteome-wide studies
Include sample size calculations or power analysis when appropriate
Example statistical workflow:
Assess DNAJC12 expression distribution across sample cohort
Correlate with clinicopathological parameters using appropriate tests
Perform Kaplan-Meier analysis and log-rank tests for survival outcomes
Conduct univariate and multivariate Cox regression
Evaluate predictive performance for treatment response
This systematic statistical approach enables researchers to robustly evaluate DNAJC12's prognostic and predictive significance in clinical samples.
Resolving contradictory findings about DNAJC12 requires systematic methodological approaches and careful interpretation:
Context-dependent experimental design:
Tissue-specific analyses:
Acknowledge that DNAJC12 may function differently across tissue types
Design targeted experiments within specific tissue contexts
Compare mechanisms directly between tissues showing opposing effects
Cellular microenvironment considerations:
Evaluate DNAJC12 function under different stress conditions (e.g., ER stress, hypoxia)
Consider tumor microenvironment factors that may influence function
Test function in 2D vs. 3D culture systems or in vivo models
Molecular mechanism investigation:
Pathway-specific analyses:
Interactome characterization:
Compare DNAJC12 protein interaction partners across different cell types
Identify tissue-specific interactors that might explain divergent functions
Use co-immunoprecipitation followed by mass spectrometry in different cellular contexts
Technical reconciliation:
Antibody validation across studies:
Verify antibody specificity for DNAJC12 isoforms used in contradictory studies
Ensure antibodies detect the same protein regions
Consider epitope availability in different experimental conditions
Isoform-specific analysis:
Integrative data analysis:
Multi-omics approach:
Compare transcriptomic and proteomic data from the same samples
Integrate with epigenetic, metabolomic, or phosphoproteomic data
Look for patterns that might explain context-dependent functions
Meta-analysis:
Systematically review all published data on DNAJC12 across cancer types
Apply statistical methods to identify factors associated with contradictory findings
Develop testable hypotheses to explain discrepancies
Reconciliation example:
"The dual nature of DNAJC12 as both a tumor suppressor in breast cancer and an oncogene in lung cancer can be reconciled by examining its differential interaction with key signaling pathways. In breast cancer, particularly ER-positive subtypes, DNAJC12 may suppress tumor progression through mechanisms distinct from its activity in other cancers. Our experiments comparing DNAJC12 interactomes between these cancer types revealed tissue-specific binding partners that explain these divergent functions."
This methodological framework enables researchers to systematically address contradictory findings and develop a more nuanced understanding of DNAJC12's context-dependent functions.
Accurate quantification of DNAJC12 protein expression by immunohistochemistry requires standardized methodologies:
Scoring systems:
H-score method:
Allred scoring:
Combines proportion score (0-5) and intensity score (0-3)
Yields total scores from 0-8
Commonly used in breast cancer biomarker assessment
Quick score:
Assigns values for proportion of positive cells (1-6) and average intensity (0-3)
Results in scores ranging from 0-18
Subcellular localization assessment:
Document predominant localization:
Digital pathology approaches:
Whole slide scanning with image analysis software
Algorithm-based quantification:
Measure staining intensity on continuous scale
Calculate percentage of positive cells objectively
Apply tissue segmentation to focus on regions of interest
Reduces inter-observer variability and increases reproducibility
Quality control measures:
Standardize IHC protocol:
Consistent fixation, processing, antigen retrieval
Batch staining to minimize technical variability
Include positive and negative controls in each run
Multiple scorer validation:
Have at least two independent pathologists score samples
Calculate inter-observer agreement (kappa statistic)
Resolve discrepancies through consensus scoring
Stratification for clinical correlation:
Dichotomization approaches:
Median-based cutoffs to define high vs. low expression
ROC curve analysis to determine optimal threshold
Consider quartile analysis (comparing highest vs. lowest quartiles)
Clinical correlation:
Data presentation:
| Expression Category | Scoring Range | Clinical Correlation | Patient Outcome |
|---|---|---|---|
| Low DNAJC12 | H-score ≤ median | Associated with ER-negative status | Poor prognosis in luminal subtypes |
| Moderate DNAJC12 | H-score between median and upper quartile | Variable associations | Intermediate outcomes |
| High DNAJC12 | H-score ≥ upper quartile | Associated with ER-positive status | Better prognosis in luminal subtypes |
This methodological framework ensures standardized, reproducible quantification of DNAJC12 protein expression in tissue samples, facilitating reliable biomarker assessment across research studies.
Evaluating DNAJC12 as a potential therapeutic target requires a systematic experimental approach:
Target validation studies:
Expression correlation with clinical outcomes:
Functional genomics:
CRISPR-Cas9 knockout or knockdown of DNAJC12
siRNA/shRNA-mediated silencing
Assess effects on:
Cell proliferation, migration, invasion
Apoptosis resistance
Treatment sensitivity
Mechanistic investigations:
Pathway analysis:
Interactome mapping:
Therapeutic modulation strategies:
For cancers where DNAJC12 acts as an oncogene:
Design inhibitors targeting DNAJC12-specific functions
Develop proteolysis-targeting chimeras (PROTACs) for DNAJC12 degradation
Screen for compounds disrupting key DNAJC12 protein interactions
For cancers where DNAJC12 acts as a tumor suppressor:
Explore strategies to restore or enhance DNAJC12 expression
Investigate epigenetic mechanisms of DNAJC12 downregulation
Consider synthetic lethal approaches in DNAJC12-low cancers
Preclinical models:
Cell line panels:
Test effects across multiple cell lines representing different:
Cancer types (breast, lung, gastric, etc.)
Molecular subtypes
DNAJC12 expression levels
In vivo models:
Xenograft models with DNAJC12 modulation
Patient-derived xenografts (PDXs)
Genetically engineered mouse models
Biomarker development:
Treatment response prediction:
Resistance mechanisms:
Investigate DNAJC12's role in treatment resistance
Determine if targeting DNAJC12 can overcome resistance
This comprehensive experimental framework allows researchers to systematically evaluate DNAJC12's potential as a therapeutic target, considering its context-dependent roles across different cancer types.
Antibody validation status:
Confirm the specificity of DNAJC12 antibodies used in the study
Consider whether appropriate validation experiments were performed
Evaluate if multiple antibodies targeting different epitopes yielded consistent results
Review controls used (positive, negative, isotype controls)
Context-dependent functions:
Recognize that DNAJC12 exhibits tissue-specific roles:
Consider cell type, disease state, and experimental conditions
Isoform specificity:
Determine which DNAJC12 isoform was detected (e.g., isoform a is commonly studied)
Consider whether the antibody can distinguish between different isoforms
Evaluate if functional differences between isoforms were addressed
Methodology considerations:
Assess technical aspects of antibody applications (dilutions, incubation conditions)
Consider differences between detection methods (Western blot vs. IHC vs. IF)
Evaluate quantification methods used (scoring systems, image analysis approaches)
Review statistical analyses and thresholds for significance
Integration with other data types:
Consider correlation between protein and mRNA expression data
Evaluate functional validation of antibody-based findings
Assess how findings relate to known DNAJC12 biology (chaperone function, stress responses)
These considerations enable researchers to critically evaluate DNAJC12 antibody research, identify potential limitations, and develop appropriate interpretations that advance understanding of DNAJC12 biology in health and disease.
DNAJC12 antibody research is poised for significant advances in several key areas:
Development of isoform-specific antibodies:
Creating antibodies with enhanced specificity for distinct DNAJC12 isoforms
Enabling detailed studies of isoform-specific functions and localization
Allowing for differential detection of isoforms across tissues and disease states
Single-cell applications:
Adapting DNAJC12 antibodies for single-cell protein analysis
Combining with transcriptomics for multi-omic cellular profiling
Revealing cell-to-cell heterogeneity in DNAJC12 expression within tumors
Post-translational modification detection:
Developing antibodies specific to phosphorylated, ubiquitinated, or otherwise modified DNAJC12
Understanding how modifications regulate DNAJC12 function
Correlating modification states with stress responses and disease progression
Therapeutic applications:
Using DNAJC12 antibodies for targeted drug delivery to cancer cells
Developing antibody-drug conjugates for cancers overexpressing DNAJC12
Creating therapeutic antibodies disrupting oncogenic DNAJC12 interactions
Companion diagnostics:
Standardizing DNAJC12 IHC protocols for clinical application
Developing antibody-based diagnostic tests predicting treatment response
Creating point-of-care tests based on DNAJC12 detection
Technological integration:
Combining DNAJC12 antibodies with emerging technologies:
Spatial transcriptomics
Mass cytometry (CyTOF)
Digital spatial profiling
Providing unprecedented insights into DNAJC12's role in tissue architecture
Mechanistic investigations:
Utilizing antibodies to map comprehensive DNAJC12 interactomes across contexts
Understanding tissue-specific molecular networks explaining contextual functions
Elucidating the role of DNAJC12 in chaperone networks and proteostasis