MAP3K7 (Ab-271) Antibody

What is the target specificity of MAP3K7 (Ab-271) Antibody?

The MAP3K7 (Ab-271) Antibody is a polyclonal antibody that specifically targets the region surrounding the phosphorylation site of serine 271 (V-D-S(p)-K-A) in human MAP3K7 protein. It was developed using a synthesized non-phosphopeptide derived from this region as the immunogen . The antibody demonstrates cross-reactivity with both human and mouse MAP3K7 proteins, making it suitable for comparative studies across these species .

What are the validated applications for MAP3K7 (Ab-271) Antibody?

This antibody has been validated for several research applications including:

• Western Blotting (WB): Recommended dilution range of 1:500-1:3000

• Enzyme-Linked Immunosorbent Assay (ELISA): Recommended dilution range of 1:2000-1:10000

The antibody has been tested on extracts from various cell lines including HeLa, 293, and cos-7 cells, confirming its specificity and utility across different experimental systems .

How does MAP3K7 (Ab-271) Antibody differ from antibodies targeting other phosphorylation sites like Thr187?

While the MAP3K7 (Ab-271) Antibody specifically recognizes the Ser271 region, other antibodies like ABIN7180043 target different phosphorylation sites such as Thr187 . This distinction is crucial because different phosphorylation sites mediate distinct signaling outcomes. Thr187 phosphorylation has been established as a marker for MAP3K7 autophosphorylation and activation, particularly in complex with TAB1 . In contrast, Ser271 phosphorylation represents a different regulatory mechanism. When designing experiments to study specific MAP3K7 activation states, researchers should select antibodies targeting the relevant phosphorylation site for their pathway of interest .

What are the optimal conditions for using MAP3K7 (Ab-271) Antibody in Western blotting experiments?

For optimal Western blotting results with MAP3K7 (Ab-271) Antibody:

• Sample preparation: Prepare cell or tissue lysates in phosphate-buffered saline (without Mg²⁺ and Ca²⁺), pH 7.4, containing 150mM NaCl, 0.02% sodium azide, and protease inhibitors.

• Protein loading: Load 20-50μg of total protein per lane.

• Antibody dilution: Use at 1:500-1:3000 dilution in blocking buffer (typically 5% non-fat milk or BSA in TBST).

• Incubation conditions: Incubate primary antibody overnight at 4°C with gentle agitation.

• Detection method: For optimal visualization, use appropriate HRP-conjugated secondary antibodies followed by enhanced chemiluminescence detection.

The antibody has been validated to detect a specific band corresponding to MAP3K7 in human cell lines (HeLa, 293) and mouse cell lines (cos-7), making it suitable for comparing MAP3K7 expression across these experimental systems .

How can I validate the specificity of MAP3K7 (Ab-271) Antibody in my experimental system?

To validate antibody specificity:

• Peptide competition assay: Pre-incubate the antibody with excess synthesized peptide (the immunogen) before Western blotting. This should abolish specific binding, as demonstrated in validation studies with cos-7 cell extracts .

• Positive and negative controls: Include known MAP3K7-expressing cells (e.g., HeLa, 293) as positive controls and either MAP3K7 knockdown samples or cells with naturally low expression as negative controls.

• Molecular weight verification: Confirm that the detected band corresponds to the expected molecular weight of MAP3K7 (approximately 67 kDa).

• Multiple detection methods: Cross-validate results using alternative detection methods such as immunoprecipitation or immunohistochemistry where applicable.

• siRNA knockdown: For definitive validation, perform MAP3K7 siRNA knockdown experiments and confirm reduced signal intensity with the antibody .

What are the key signaling pathways involving MAP3K7 that can be studied using this antibody?

MAP3K7 (also known as TAK1) functions as a critical node in multiple signaling networks:

• NF-κB Signaling: MAP3K7 activates the IKK complex leading to NF-κB activation, a pathway that can be monitored through phosphorylation of NF-κB components following cell stimulation .

• MAPK Cascades: MAP3K7 activates several downstream kinases including MAP2K3/MKK3, MAP2K6/MKK6, and MAP2K7/MKK7, which in turn activate p38 MAPKs and JNKs. These pathways regulate AP-1 transcription factors .

• TGF-β/BMP Signaling: MAP3K7 mediates non-canonical signaling downstream of TGF-β and BMP receptors, affecting cell fate decisions and tissue morphogenesis .

• AMPK Signaling: MAP3K7 plays a pivotal role in the LKB1/AMPK signaling axis, which governs cellular metabolism and energy homeostasis. This pathway is activated by metabolic stressors like oligomycin, metformin, and ischemia .

• Toll-Like Receptor (TLR) Signaling: MAP3K7 is activated downstream of TLRs and contributes to innate immune responses .

Using the MAP3K7 (Ab-271) Antibody, researchers can monitor MAP3K7 expression and post-translational modifications in these pathways under various experimental conditions .

How does MAP3K7 phosphorylation at Ser271, detected by this antibody, differ functionally from phosphorylation at other sites?

MAP3K7 undergoes multiple phosphorylation events that regulate its activity and function:

• Ser271 phosphorylation (detected by MAP3K7 (Ab-271) Antibody) represents a regulatory modification that differs from the well-characterized Thr187 autophosphorylation site. While Thr187 phosphorylation is directly associated with kinase activation when MAP3K7 complexes with TAB1, Ser271 phosphorylation may represent a distinct regulatory mechanism .

• Comparative studies have shown that mutations affecting different phosphorylation sites in MAP3K7 can lead to distinct phenotypic outcomes. For example, in frontometaphyseal dysplasia type 2 (FMD2) versus cardiospondylocarpofacial syndrome (CSCF), mutations differently affect Thr187 autophosphorylation and downstream NF-κB signaling, creating distinct "molecular fingerprints" .

• Research shows that FMD2-related MAP3K7 mutations result in equal or increased levels of Thr187 autophosphorylation compared to wild-type, while most CSCF-related mutations show significantly reduced Thr187 autophosphorylation, suggesting gain-of-function versus loss-of-function effects respectively .

• For comprehensive analysis of MAP3K7 activation states, researchers should consider using antibodies targeting multiple phosphorylation sites (including both Ser271 and Thr187) to capture the full spectrum of MAP3K7 regulation in their experimental system .

How can MAP3K7 (Ab-271) Antibody be utilized in studying T-cell acute lymphoblastic leukemia (T-ALL)?

MAP3K7 has significant implications in T-ALL research as demonstrated by several studies:

• Detection of MAP3K7 expression in T-ALL samples: The antibody can be used to assess MAP3K7 protein levels in patient samples and cell lines. Research has shown that MAP3K7 is deleted in approximately 10% and point-mutated in approximately 1% of children with T-ALL .

• Correlation with genetic alterations: MAP3K7 deletions have been associated with the occurrence of SIL-TAL1 fusions and a mature immunophenotype in T-ALL. Researchers can use the antibody to investigate correlations between MAP3K7 expression and these genetic markers .

• Functional studies: Experimental depletion of MAP3K7 in T-ALL cell lines (CCRF-CEM, Jurkat, MOLT-4) slows proliferation and induces apoptosis. The antibody can be used to verify knockdown efficiency and monitor residual MAP3K7 expression in such studies .

• Pathway analysis: Despite the proliferation effects, MAP3K7 depletion in T-ALL does not appear to alter NF-κB signaling as initially hypothesized. The antibody can help investigate alternative pathways through which MAP3K7 influences T-ALL cell survival .

• Therapeutic target assessment: The complete absence of homozygous MAP3K7 deletions in T-ALL patients suggests that some level of MAP3K7 expression is indispensable for T-lymphoblasts, positioning it as a potential therapeutic target .

What is the role of MAP3K7 in genetic disorders like frontometaphyseal dysplasia type 2 (FMD2) and cardiospondylocarpofacial syndrome (CSCF)?

MAP3K7 mutations cause distinct genetic disorders with different molecular mechanisms:

• Genotype-phenotype correlations: Different mutations in MAP3K7 lead to two distinct disorders—frontometaphyseal dysplasia type 2 (FMD2) and cardiospondylocarpofacial syndrome (CSCF). The MAP3K7 (Ab-271) Antibody can be used alongside other phospho-specific antibodies to establish molecular signatures of these conditions .

• Functional classification of mutations:

  • FMD2-causing mutations exhibit gain-of-function effects with increased or unchanged MAP3K7 Thr187 autophosphorylation

  • CSCF-causing mutations show loss-of-function effects with significantly reduced Thr187 autophosphorylation

• Clinical implications: Patients with pathogenic MAP3K7 mutations are at risk for severe cardiac disease and show symptoms associated with connective tissue disorders. Additionally, CSCF phenotypes overlap with Noonan syndrome (NS), suggesting MAP3K7 should be considered in differential diagnosis of these conditions .

• Research methodology: Using multiple phospho-specific antibodies, including MAP3K7 (Ab-271) Antibody, researchers can characterize the activation state of wild-type and mutant MAP3K7 in patient-derived samples or model systems .

How can the MAP3K7 (Ab-271) Antibody be incorporated into phospho-proteomics studies?

For phospho-proteomics applications involving MAP3K7:

• Sample enrichment strategies: The antibody can be used for immunoprecipitation of MAP3K7 prior to mass spectrometry analysis, allowing for enrichment of MAP3K7 and its interacting partners.

• Validation of phospho-proteomic findings: Mass spectrometry-identified phosphorylation events on MAP3K7 can be validated using the antibody in Western blotting experiments to confirm site-specific modifications.

• Kinase assays: When studying MAP3K7 kinase activity, the antibody can be used to immunoprecipitate the active kinase for in vitro kinase assays with substrate proteins.

• Quantitative phospho-proteomic workflows: In SILAC or TMT-based quantitative proteomics, the antibody can help validate dynamic changes in MAP3K7 phosphorylation states under different experimental conditions.

• Chemical proteomics approaches: As demonstrated in studies like the one using WEL028 probe for kinase target engagement, antibodies like MAP3K7 (Ab-271) can validate kinase-specific binding in chemical proteomics experiments .

What methodologies can be employed to study the interaction between MAP3K7 and TAB1 using this antibody?

To investigate MAP3K7-TAB1 interactions:

• Co-immunoprecipitation: The MAP3K7 (Ab-271) Antibody can be used to pull down MAP3K7 complexes, followed by immunoblotting for TAB1 to assess their interaction. Research shows that MAP3K7 interaction with TAB1 results in autophosphorylation at Thr187 and slower migration of both proteins on Western blots .

• Proximity ligation assay (PLA): This technique can visualize MAP3K7-TAB1 interactions in situ by using the MAP3K7 (Ab-271) Antibody alongside a TAB1-specific antibody.

• Immunofluorescence co-localization: The antibody can be used in conjunction with TAB1 staining to assess subcellular co-localization patterns.

• FRET/BRET approaches: For live-cell studies, the antibody can help validate expression constructs used in fluorescence or bioluminescence resonance energy transfer experiments designed to monitor MAP3K7-TAB1 interactions.

• Functional validation: When studying MAP3K7 mutants, the antibody can help assess how mutations affect both MAP3K7 expression levels and its interaction with TAB1, as demonstrated in studies comparing wild-type MAP3K7 with disease-causing mutants .

What are the common challenges in detecting MAP3K7 phosphorylation and how can they be addressed?

Researchers may encounter several challenges when detecting MAP3K7 phosphorylation:

• Phosphorylation site-specific detection:

  • Problem: Different phosphorylation sites (Ser271, Thr187, Ser412) have distinct functions and dynamics.

  • Solution: Use site-specific antibodies like MAP3K7 (Ab-271) for targeted analysis, and consider multi-site analysis for comprehensive studies .

• Signal-to-noise ratio:

  • Problem: Low abundance of phosphorylated MAP3K7 in resting cells.

  • Solution: Incorporate phosphatase inhibitors in lysis buffers, use phospho-enrichment strategies, and optimize stimulation protocols (e.g., TNF-α treatment) to increase phosphorylation signals .

• Antibody specificity:

  • Problem: Cross-reactivity with other phosphorylated proteins.

  • Solution: Validate specificity with peptide competition assays, include appropriate controls, and verify results with genetic approaches (siRNA/shRNA) .

• Temporal dynamics:

  • Problem: Transient nature of phosphorylation events.

  • Solution: Perform careful time-course experiments after stimulation to capture optimal phosphorylation windows.

• Sample preparation:

  • Problem: Loss of phosphorylation during processing.

  • Solution: Maintain samples at 4°C, use freshly prepared buffers with phosphatase inhibitors, and minimize freeze-thaw cycles of lysates .

How can researchers optimize immunohistochemistry protocols using MAP3K7 (Ab-271) Antibody?

For optimal immunohistochemistry (IHC) results:

• Tissue fixation and processing:

  • Use 10% neutral-buffered formalin fixation for 24-48 hours

  • Process tissues using standard paraffin embedding protocols

  • Section tissues at 4-6μm thickness for optimal antibody penetration

• Antigen retrieval:

  • Heat-mediated antigen retrieval in citrate buffer (pH 6.0) for 20 minutes

  • Allow slides to cool slowly to room temperature (approximately 20 minutes)

• Blocking and antibody incubation:

  • Block with 5-10% normal serum from the species of the secondary antibody

  • Use MAP3K7 (Ab-271) Antibody at 1:50-1:100 dilution

  • Incubate overnight at 4°C in a humidified chamber

• Detection system:

  • Use a biotin-free detection system to minimize background

  • For brightfield microscopy, DAB (3,3'-diaminobenzidine) provides strong contrast

  • For fluorescence, use appropriate fluorophore-conjugated secondary antibodies

• Controls and validation:

  • Include positive control tissues with known MAP3K7 expression

  • Use peptide competition controls to verify specificity

  • Consider dual staining with cell-type specific markers for co-localization studies

How should researchers interpret variations in MAP3K7 expression and phosphorylation across different cell types?

When analyzing MAP3K7 expression and phosphorylation patterns:

• Cell type-specific baseline expression:

  • MAP3K7 is ubiquitously expressed but at varying levels across cell types

  • Establish baseline expression in your specific cell type using appropriate controls

  • For comparative studies, normalize MAP3K7 signals to housekeeping proteins

• Tissue-specific functions:

  • MAP3K7 functions differently across tissues (e.g., cardiac cells vs. T-lymphoblasts)

  • Interpret results in the context of tissue-specific signaling networks

  • Consider that MAP3K7 deletions in T-ALL are associated with specific immunophenotypes

• Activation state assessment:

  • Phosphorylation at different sites indicates distinct activation states

  • Ser271 phosphorylation (detected by this antibody) represents one regulatory modification

  • Compare with other phosphorylation sites (e.g., Thr187) for comprehensive evaluation

• Pathological contexts:

  • Altered MAP3K7 expression/phosphorylation may indicate disease states

  • In T-ALL, MAP3K7 deletions occur in ~10% of cases

  • In genetic disorders, specific mutations affect phosphorylation patterns differently

• Quantitative analysis:

  • Use densitometry for semi-quantitative comparison of Western blot signals

  • For precise quantification, consider phospho-specific ELISA

  • Present data as ratios of phosphorylated to total MAP3K7 protein

What are the implications of MAP3K7 research for understanding treatment resistance in cancer?

MAP3K7 research provides insights into treatment resistance mechanisms: