JUNB (Ab-79) Antibody
Product Specs
Target Background
- Research has indicated that the AP-1 family member JunB and retinoic acid receptor alpha (RARa) regulate catalase transcriptional activation and repression, respectively. This regulation is achieved by controlling chromatin remodeling through a histone deacetylases-dependent mechanism. PMID: 27591797
- JunB neddylation, mediated by Itch, promotes its ubiquitination-dependent degradation. PMID: 27245101
- Studies have identified a specific role for AP-1/JunB in the regulation of multiple myeloma cell proliferation, survival, and drug resistance. PMID: 27890927
- VEGF-induced endothelial migration is primarily driven by the induction of JunB, while the promotion of endothelial proliferation by VEGF is mediated by JunB-independent AP-1 family members. PMID: 26860974
- Research findings suggest that JunB plays a significant role in promoting cell invasion, migration, and distant metastasis in head and neck squamous cell carcinoma through pathways other than epithelial-to-mesenchymal transition. PMID: 26754630
- Highly recurrent mutations in JUNB have been associated with nodular lymphocyte predominant Hodgkin lymphoma. PMID: 26658840
- ETS2, HNF4A, and JUNB act as synergistic master regulators of epithelial-to-mesenchymal transition in cancer. PMID: 26926107
- PDK1 functions as a tumor promoter in human gallbladder cancer by upregulating JunB, promoting epithelial mesenchymal transformation, and cell migration. PMID: 26318166
- Research findings demonstrate that miRNA-149* may act as an oncogenic regulator in T-cell acute lymphoblastic leukemia by negatively regulating JunB. PMID: 26725775
- The MAPK pathway plays a primary role in controlling JUNB gene expression. PMID: 25662951
- JunB is likely a key target of c-Abl in the expression of p21 in Adriamycin-induced DNA damage response (DDR). PMID: 26217035
- Caveolin 2 disengages repressed Egr-1 and JunB promoters from lamin A/C through the disassembly of H3K9me3 in the inner nuclear membrane. PMID: 25753664
- JunB expression was significantly increased while cyclin-D1 expression was significantly down-regulated in pre-eclampsia relative to control placental mesenchymal stromal cells. PMID: 24780198
- Research findings uncover the oncogenic role of the JUNB/CD30 axis and its potential as a therapeutic target in ALK+ ALCL. PMID: 25145835
- These results demonstrate a unique induction of JUNB in response to kinase inhibitor therapies, which may be among the earliest events in the progression to treatment resistance. PMID: 24858691
- Apoptosis rate of HepG2 cells transformed with pEGFP-C1-wtp53/JunB was significantly higher. PMID: 23259178
- Data indicate that S100A14 is transcriptionally regulated by JunB and involved in esophageal squamous cell carcinoma cell differentiation. PMID: 24107296
- Research highlights an important role of the A2B receptor-dependent upregulation of JunB in VEGF production and potentially other AP-1-regulated events. PMID: 24136993
- JUNB was specifically expressed in human immune cells during acute liver injury. PMID: 24200694
- JunB is shown to be regulated at a post-transcriptional level during endothelial cell (EC) activation. In activated EC, the AP-1 transcription factor JunB is regulated on a post-transcriptional level. PMID: 23297064
- JunB regulates visceral smooth muscle cell contractility through effects on both myosin and the actin cytoskeleton. PMID: 23308222
- A novel mechanism has been identified by which mitosis progression and chromatid cohesion are regulated through GSK3/SCF(FBXW7)-mediated proteolysis of JunB. PMID: 22710716
- A study confirmed that JunB was upregulated in VHL-defective clear-cell renal-cell carcinoma (ccRCC) specimens through immunostaining. Short-hairpin RNA (shRNA)-mediated knockdown of JunB in 786-O and A498 VHL null ccRCC cells suppressed their invasiveness. PMID: 22020339
- Distinct mechanisms preserve the translation of programmed cell death 8 and JunB in poliovirus-infected endothelial cells. PMID: 22328780
- The upregulation of JunB induced by HGF may play a crucial role in the regulation of cell proliferation and cell invasion through MMP-9 expression. PMID: 22252121
- JunB activates aromatase promoters by maintaining JunD expression. PMID: 21393445
- The methylation of JunB and CDH13 gene promoters likely plays a role in the pathogenesis of chronic myelogenous leukemia and may have clinical significance in predicting prognosis of CML. PMID: 20030915
- JunB is a direct transcriptional activator of GzB, and GzB transcription is also promoted by NPM-ALK. PMID: 21326808
- Monoammonium glycyrrhizinate significantly stimulated JUNB expression in a human hepatoma cell line, HepG2. PMID: 21225234
- The increase in JunB expression attenuated nuclear relocation of apoptosis-inducing factor and mitochondrial Bcl-2 reduction that occurred following hydrogen peroxide exposure. PMID: 20132737
- JunB functions as a transcriptional factor and upregulates the expression of VEGF. PMID: 20056077
- Analysis shows that the overwhelming majority of JUNB alleles in both chronic phase and blast crisis samples remain unmethylated. PMID: 20006998
- When p53 dysfunction and low expression of JunB occur simultaneously, they may play a significant role in down-regulating the expression of KAI1 through synergism in hepatocellular carcinoma. PMID: 19666408
- JunB is an important regulator of erythroid differentiation. PMID: 11726656
- JunB potentiates the function of BRCA1 activation domain 1 (AD1) through a coiled-coil-mediated interaction. PMID: 12080089
- Research has demonstrated that a functional AP-1 site mediates MMP-2 transcription in cardiac cells through the binding of distinctive Fra1-JunB and FosB-JunB heterodimers. The synthesis of MMP-2 is considered to be independent of the AP-1 transcriptional complex. PMID: 12371906
- Research has, for the first time, revealed amplification and expression patterns of JUNB in primary cutaneous lymphomas. PMID: 12393503
- Real-time RT-PCR provided further insights into the role of JunB in human CML. Expression levels were significantly impaired in CML cases. In the promoter area, most of the CpG sites were methylated only in CML cases. PMID: 12506033
- C/EBPalpha and PKC/delta affect the expression of this gene and monocyte differentiation. PMID: 12522006
- Expression of junB was induced by TPA and Saikosaponin a during 30 min to 6 h of treatment. PMID: 12592382
- JunB was strongly expressed in T-cell lymphomas, but non-Hodgkin B-cell lymphomas do not or only weakly express JunB. PMID: 12907453
- Transcription factor c-Jun plays a principal role in the down-regulation of mdr-1 expression and induction of apoptosis in salvicine-treated human MDR K562/A02 cells. PMID: 12907627
- The IGFBP3, hRas, JunB, Egr-1, Id1, and MIDA1 genes were up-regulated in psoriatic involved skin compared with uninvolved skin. PMID: 16552541
- 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole sensitivity-inducing factor (DSIF)- and NELF-mediated transcriptional pausing has a dual function in regulating immediate-early expression of the human junB gene. PMID: 16880520
- JunB and JunD contribute opposing effects; JunB activated whereas JunD repressed heme oxygenase-1 expression in human renal epithelial cells. PMID: 17204476
- Results suggest that HTLV-I HBZ-SP1- mediated sequestration of JunB to the HBZ-SP1 nuclear bodies may be causing the repression of JunB activity in vivo. PMID: 17306025
- JunB is a critical target of mTOR and is translationally regulated in NPM-ALK-positive lymphomas. PMID: 17690253
- Constitutive action of aberrantly expressed JunB on hypomethylated CD30 CpG islands of lymphocytes triggers CD30 induction and initiates activation of the JunB-CD30-JunB loop, essential to the pathogenesis of HL and ALCL. PMID: 17965727
- JunB levels, which are high in S phase, drop during mid- to late G2 phase due to accelerated phosphorylation-dependent degradation by the proteasome, and are required for subsequent reduction of cyclin A2 levels in prometaphase. PMID: 18391017
- Sumoylation of JunB regulates its ability to induce cytokine gene transcription and likely plays a critical role in T cell activation. PMID: 18424718
Q&A
How do I validate the specificity of JUNB (Ab-79) antibodies in phosphorylation-dependent assays?
Validation requires a multi-step approach. First, perform a peptide-blocking experiment by pre-incubating the antibody with its immunogen phosphopeptide (e.g., G-A-S(p)-L-K for Ser79 ). A ≥70% reduction in signal intensity confirms specificity. Second, use siRNA-mediated JUNB knockdown in cell lines to demonstrate loss of the target band in WB. Include non-phosphorylated peptide controls to rule out cross-reactivity . For IHC/IF, compare staining patterns in wild-type versus JUNB knockout tissues .
Table 1: Validation Techniques for Phospho-Specific Antibodies
| Method | Advantages | Limitations |
|---|---|---|
| Peptide Blocking | Direct evidence of epitope binding | Requires synthetic phosphopeptides |
| Knockdown/KO Models | Confirms target dependency | Time-intensive; may affect viability |
| Cross-Species WB | Tests evolutionary conservation | Limited to species with Ser79 homology |
What criteria should guide the selection of monoclonal vs. polyclonal JUNB (Ab-79) antibodies?
Monoclonal antibodies (e.g., PCRP-JUNB-3G11 ) offer batch-to-batch consistency, ideal for longitudinal studies. Polyclonal antibodies (e.g., SAB’s Rabbit polyclonal ) often exhibit higher sensitivity for low-abundance targets but require rigorous cross-reactivity checks. For phospho-specific assays, polyclonals may better detect heterogeneous phosphorylation states, while monoclonals reduce off-target noise in multiplex imaging .
How can I optimize JUNB (Ab-79) antibody protocols for formalin-fixed, paraffin-embedded (FFPE) tissues?
Antigen retrieval is critical. Use citrate buffer (pH 6.0) at 95°C for 20 minutes, followed by enzymatic digestion with 0.1% trypsin for 10 minutes. For phospho-epitopes, avoid alkaline buffers (pH >8) to prevent epitope degradation . Titrate antibody concentrations from 0.5–5 µg/mL, as overfixation increases non-specific binding. Include a non-immune IgG control and validate with a non-phosphorylated JunB antibody to distinguish phosphorylation-specific signals .
How do I resolve discrepancies in JUNB (Ab-79) antibody signals across experimental models?
Unexpected results often arise from species-specific phosphorylation kinetics or epitope accessibility. For example, murine JunB shares 98% homology with human Ser79, but phosphorylation timing differs during cell cycle progression . If WB signals conflict with IF data:
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Verify post-lysis modifications: Add phosphatase inhibitors (e.g., 1 mM Na3VO4) to preserve phosphorylation during tissue homogenization.
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Assess subcellular localization: Nuclear extraction (via NE-PER kits) clarifies whether signal loss reflects cytoplasmic mislocalization.
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Cross-validate with orthogonal methods: Combine IP-MS with JUNB (Ab-79) pull-downs to identify co-purifying kinases (e.g., MAPK) that modulate Ser79 phosphorylation .
What strategies enable multiplex detection of phosphorylated JunB alongside other AP-1 components?
Design a sequential staining protocol:
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First round: Apply JUNB (Ab-79) antibody (rabbit host ) with Cy3 tyramide signal amplification (TSA).
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Heat denaturation: Incubate slides at 70°C in PBS to strip antibodies without damaging epitopes.
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Second round: Use mouse anti-c-Fos (e.g., monoclonal 4A6) with Alexa Fluor 488. Validate with single-antibody controls to confirm no residual signal post-stripping . For flow cytometry, select conjugates with minimal spectral overlap (e.g., PE-Cy7 for JUNB, APC for c-Jun) .
Table 2: Multiplex Assay Optimization Parameters
| Parameter | Recommendation | Rationale |
|---|---|---|
| Antibody Host | Use distinct host species | Prevents cross-reactivity |
| TSA System | HRP-based with fluorophore tyramides | Enhances sensitivity for low-abundance targets |
| Stripping Efficiency | Verify via no-primary-antibody control | Ensures signal removal between rounds |
How can JUNB (Ab-79) antibodies be integrated with omics approaches to study AP-1 regulatory networks?
Combine ChIP-seq with phospho-specific flow cytometry:
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Sort cells into Ser79-phosphorylated (JUNB (Ab-79)+) and non-phosphorylated populations via FACS .
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Perform ChIP-seq on sorted cells using a pan-JunB antibody to map genome-wide binding sites.
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Cross-reference with RNA-seq to link phosphorylation states to target gene expression (e.g., IL2 or CDKN1A). For kinase association studies, immunoprecipitate JunB (Ab-79) complexes and analyze via LC-MS/MS to identify bound kinases (e.g., JNK1) .
