Phospho-ITGB1 (Thr789) Antibody

What is Phospho-ITGB1 (Thr789) and why is it important in research?

Phospho-ITGB1 (Thr789) refers to Integrin beta-1 that is specifically phosphorylated at the threonine residue at position 789. This phosphorylation site plays a crucial role in regulating integrin-mediated cellular functions including adhesion, migration, and signaling pathways. Integrin beta-1 serves as a receptor for various extracellular matrix components including collagen, fibronectin, and laminin, making it integral to cell-matrix interactions and downstream signaling events. The phosphorylation status at Thr789 modulates these interactions, thereby affecting critical cellular processes such as differentiation, proliferation, and survival . Research focusing on this phosphorylation site contributes to understanding mechanisms of cell adhesion regulation, cancer metastasis, and other pathological conditions where integrin signaling is dysregulated .

What are the standard specifications of commercially available Phospho-ITGB1 (Thr789) antibodies?

Commercial Phospho-ITGB1 (Thr789) antibodies typically exhibit the following specifications:

These antibodies are designed to specifically recognize the phosphorylated form of ITGB1 at Thr789, distinguishing it from unphosphorylated ITGB1 or other phosphorylation sites on the protein .

How does phosphorylation at Thr789 affect Integrin beta-1 function?

Phosphorylation at Thr789 serves as a post-translational modification that regulates integrin beta-1's functional properties. This specific phosphorylation event affects:

• Integrin activation state and affinity for extracellular matrix ligands

• Recruitment of cytoskeletal and signaling proteins to integrin adhesion complexes

• Turnover and recycling of integrin receptors at the cell surface

• Cross-talk with other signaling pathways

Research indicates that phosphorylation at this site can be induced by various stimuli, including growth factors, cytokines, and mechanical stress. For example, treatment of THP-1 cells with IFN-gamma for 15 minutes induces phosphorylation at this site, suggesting its role in cytokine-mediated signaling pathways . Similarly, treatment of HeLa and HepG2 cells with Paclitaxel also affects the phosphorylation status at this site, indicating potential involvement in microtubule-dependent processes and cell cycle regulation .

What are the recommended experimental conditions for Western blot using Phospho-ITGB1 (Thr789) antibody?

For optimal Western blot results with Phospho-ITGB1 (Thr789) antibody, the following methodological approach is recommended:

• Sample preparation:

  • For cell lines: Use membrane-enriched extracts (30 μg lysate) for optimal detection

  • Consider treatments that induce phosphorylation (e.g., Paclitaxel, serum starvation followed by mitotic arrest)

• Antibody dilution:

  • Working dilution range: 1:500 to 1:3000 for Western blot

  • Optimal starting dilution: 1:500 (as demonstrated for HEK293T lysates, mouse kidney tissue, and rat liver tissue samples)

• Blocking and incubation conditions:

  • Use 5% BSA in TBST for blocking and antibody dilution to minimize background

  • Incubate with primary antibody overnight at 4°C for best results

• Controls to include:

  • Positive control: HeLa cells treated with 100 ng/mL taxol for 16 hours (induces mitotic arrest and ITGB1 phosphorylation)

  • Specificity control: Pre-incubation with immunogen phosphopeptide (should block signal)

  • Phospho-specificity control: Treat membrane with phosphatase (should eliminate signal)

• Detection system:

  • HRP-conjugated secondary antibodies at 1:5000 dilution provide optimal signal-to-noise ratio

These conditions have been validated across multiple cell types and tissue samples, demonstrating reliable detection of phosphorylated ITGB1 at approximately 130-140 kDa .

How can I optimize immunofluorescence protocols for Phospho-ITGB1 (Thr789) antibody?

For successful immunofluorescence/immunocytochemistry (IF/ICC) experiments using Phospho-ITGB1 (Thr789) antibody, the following optimization steps are recommended:

• Cell preparation and fixation:

  • Fix cells with 4% paraformaldehyde for optimal epitope preservation

  • Permeabilize with 0.1% Triton X-100 for 10 minutes to allow antibody access

• Antibody dilution and incubation:

  • Use dilution range of 1:100 to 1:500 (start with 1:250)

  • Incubate overnight at 4°C in a humidified chamber

• Cell treatment considerations:

  • Treatment with cytokines (e.g., 100 ng/mL IFN-gamma for 15 minutes) has been shown to induce phosphorylation, providing a positive control

  • Include untreated cells as negative controls

• Visualization and co-staining:

  • Counter-stain nuclei with DAPI (blue)

  • Consider actin staining (red) for cell structure visualization

  • Use appropriate filters to detect primary antibody (green channel typically used)

• Controls:

  • No primary antibody control to assess background fluorescence

  • Untreated cells to establish baseline phosphorylation levels

  • Competing phosphopeptide control to verify specificity

This protocol has been validated in THP-1 cells and demonstrates specific detection of phosphorylated ITGB1 at Thr789 with minimal background signal .

What cell-based ELISA approaches can be used with Phospho-ITGB1 (Thr789) antibody?

Cell-based ELISA provides a quantitative approach for measuring Phospho-ITGB1 (Thr789) levels directly in cultured cells. The methodology involves:

• Assay principle and format:

  • Cells are fixed directly in multi-well plates

  • Anti-Phospho-ITGB1 (Thr789) antibody captures the phosphorylated protein

  • HRP-conjugated secondary antibodies enable colorimetric detection

  • Indirect ELISA format allows for qualitative determination of phosphorylation status

• Normalization strategies:

  • Anti-GAPDH antibody serves as an internal positive control

  • Crystal Violet whole-cell staining determines cell density for normalization

  • Anti-total ITGB1 antibody enables phospho-to-total protein ratio calculations

• Experimental considerations:

  • Plate cells at consistent density (typically 1-3 × 10⁴ cells/well)

  • Apply stimulation conditions to induce phosphorylation

  • Use antibody at 1:1000 dilution for optimal results

• Data analysis:

  • Calculate phospho-ITGB1/total ITGB1 ratios to account for expression differences

  • Normalize to cell number using Crystal Violet data

  • Compare treated vs. untreated conditions to determine fold-changes in phosphorylation

This approach is particularly valuable for screening multiple stimulation conditions or inhibitor treatments simultaneously, providing insight into signaling pathways regulating ITGB1 phosphorylation at Thr789 .

How can I verify the specificity of the Phospho-ITGB1 (Thr789) antibody signal?

Verifying antibody specificity is crucial for confident data interpretation. The following multi-step validation approach is recommended:

• Peptide competition assay:

  • Pre-incubate antibody with the immunogen phosphopeptide (derived from human Integrin beta-1 around Thr789)

  • A specific antibody will show signal elimination when pre-incubated with the phosphopeptide

  • Published data confirms that only the immunogen phosphopeptide blocks the signal, demonstrating specificity

• Phosphatase treatment:

  • Treat membrane or fixed cells with lambda protein phosphatase

  • A phospho-specific antibody will show signal elimination after phosphatase treatment

  • Research has verified that phosphatase treatment eliminates the signal, confirming phospho-specificity

• Use of known inducers of phosphorylation:

  • Treatment with Paclitaxel has been demonstrated to increase Thr789 phosphorylation in HeLa and HepG2 cells

  • IFN-gamma treatment (100 ng/mL for 15 minutes) induces phosphorylation in THP-1 cells

  • Mitotic arrest through taxol treatment (100 ng/mL for 16 hours) increases phosphorylation

• Control samples:

  • Include both positive controls (cell lines with known expression) and negative controls

  • Use multiple cell types to verify consistent detection (HEK293T, HeLa, HepG2, and THP-1 cells have been validated)

These validation steps collectively provide strong evidence for antibody specificity when all criteria are met, ensuring reliable experimental results and interpretations .

What are the common issues in Western blot detection of Phospho-ITGB1 (Thr789) and how can they be resolved?

When performing Western blots with Phospho-ITGB1 (Thr789) antibody, researchers may encounter several technical challenges:

• Weak or absent signal:

  • Cause: Insufficient phosphorylation or low protein abundance

  • Solution: Enrich membrane fractions (30 μg lysate recommended), use phosphatase inhibitors in lysis buffer, and consider cell stimulation (e.g., Paclitaxel treatment)

  • Technical approach: Use membrane enriched extracts rather than whole cell lysates for enhanced detection

• High background or non-specific bands:

  • Cause: Suboptimal blocking or antibody concentration

  • Solution: Use 5% BSA instead of milk for blocking, optimize antibody dilution (start with 1:500), and increase washing stringency

  • Validation: Run peptide competition assay to distinguish specific from non-specific signals

• Inconsistent results between experiments:

  • Cause: Variable phosphorylation status due to cell conditions

  • Solution: Standardize cell culture conditions, control cell density and passage number, and ensure consistent treatment protocols

  • Example: Serum starvation followed by specific treatments (like 100 ng/mL taxol for 16 hours) provides reproducible phosphorylation

• Inability to detect phosphorylation changes:

  • Cause: Baseline phosphorylation masking inducible changes

  • Solution: Serum-starve cells before treatment, use appropriate time points for detection, and include total ITGB1 antibody for normalization

  • Experimental approach: Compare serum-starved vs. stimulated conditions side-by-side

These troubleshooting approaches have been validated across multiple cell types and experimental systems, ensuring reliable detection of phosphorylated ITGB1 at Thr789 .

How should I interpret changes in Phospho-ITGB1 (Thr789) levels in different experimental conditions?

Interpreting changes in Phospho-ITGB1 (Thr789) levels requires consideration of multiple factors:

• Normalization strategies:

  • Always normalize phospho-signal to total ITGB1 levels to account for expression changes

  • Alternative normalization to housekeeping proteins (GAPDH) or total protein staining may be appropriate in some contexts

  • In cell-based assays, normalize to cell number using Crystal Violet staining

• Temporal dynamics:

  • Phosphorylation events are often transient

  • Conduct time-course experiments to capture kinetics (e.g., 5, 15, 30, 60 minutes post-stimulation)

  • Consider both rapid signaling events and sustained phosphorylation patterns

• Context-dependent interpretation:

  • Cell type-specific responses may vary (compare results across cell lines)

  • Integrin activation status affects phosphorylation response

  • Cell adhesion state (adherent vs. suspension) influences baseline phosphorylation

• Biological significance thresholds:

  • Statistical significance doesn't always equate to biological relevance

  • Consider fold-changes in phosphorylation relative to baseline

  • Correlate phosphorylation changes with functional outcomes (adhesion, migration, etc.)

• Integration with other signaling pathways:

  • ITGB1 phosphorylation at Thr789 occurs in context of other modifications

  • Consider parallel analysis of related signaling molecules

  • Research indicates connections to cell cycle regulation (evidenced by Paclitaxel effects)

Evidence from experimental systems demonstrates that changes in phosphorylation at Thr789 can be induced by specific treatments (IFN-gamma, Paclitaxel) and correlate with altered cellular functions, supporting the biological significance of these observations .

How can Phospho-ITGB1 (Thr789) antibody be used to investigate integrin-mediated mechanotransduction?

Integrin beta-1 plays a critical role in mechanotransduction—the process by which cells convert mechanical stimuli into biochemical signals. Phospho-ITGB1 (Thr789) antibody enables sophisticated investigation of this process through:

• Mechanical stimulation protocols:

  • Apply defined mechanical forces (stretch, shear stress, compression) to cells

  • Monitor Thr789 phosphorylation kinetics in response to force application

  • Compare with biochemical stimulation (growth factors, cytokines) to distinguish pathways

• Spatial analysis of phosphorylation:

  • Use immunofluorescence to visualize subcellular localization of phosphorylated ITGB1

  • Analyze phosphorylation at focal adhesions vs. non-adhesion membrane regions

  • Implement super-resolution microscopy to examine nanoscale organization

• Force-response relationships:

  • Correlate force magnitude with phosphorylation levels

  • Analyze threshold forces required for phosphorylation

  • Examine how cell and ECM stiffness modulate phosphorylation responses

• Multi-parametric analysis:

  • Combine phospho-ITGB1 detection with markers of focal adhesion maturation

  • Co-stain for actin cytoskeleton remodeling and phosphorylated downstream effectors

  • Use the validated IF/ICC protocol with 4% paraformaldehyde fixation and careful permeabilization

• Inhibitor approaches:

  • Apply specific inhibitors of known upstream kinases to determine pathway dependencies

  • Use cytoskeletal disruptors to examine force-transmission requirements

  • Compare phosphorylation patterns in cells with genetic modifications in mechanosensing components

These methodologies provide insight into how mechanical forces regulate integrin function through site-specific phosphorylation, with potential implications for understanding mechanobiology in health and disease.

What is the relationship between ITGB1 Thr789 phosphorylation and cell cycle regulation?

Research evidence suggests a significant connection between ITGB1 Thr789 phosphorylation and cell cycle regulation:

• Mitotic phosphorylation patterns:

  • Experimental data shows increased Thr789 phosphorylation in mitotic HeLa cells

  • Treatment with 100 ng/mL taxol for 16 hours (inducing mitotic arrest) enhances phosphorylation

  • Phosphorylation patterns change throughout different cell cycle phases

• Methodological approaches for investigation:

  • Synchronize cells at different cell cycle stages (double thymidine block, nocodazole arrest)

  • Perform flow cytometry with phospho-specific antibody to correlate with cell cycle markers

  • Use the validated Western blot protocol with specific controls for phospho-specificity

• Functional implications:

  • Phosphorylation may regulate integrin-dependent adhesion during mitosis

  • Could impact post-mitotic spreading and re-attachment

  • May facilitate cross-talk between adhesion signaling and cell cycle control mechanisms

• Experimental design considerations:

  • Compare adherent vs. rounded mitotic cells

  • Analyze phosphorylation in relation to focal adhesion disassembly/reassembly

  • Examine co-localization with mitotic spindle components

• Kinase-phosphatase regulation:

  • Identify candidate kinases responsible for mitotic phosphorylation

  • Examine phosphatase activity during mitotic exit

  • Use phosphatase treatment as a control to verify phospho-specificity

This research direction provides insight into how adhesion signaling and cell cycle progression are integrated at the molecular level, with implications for understanding dysregulated cell division in cancer and other pathological states.

How can contradictory findings regarding ITGB1 Thr789 phosphorylation be reconciled through methodological refinements?

Researchers occasionally encounter contradictory findings regarding ITGB1 Thr789 phosphorylation. These discrepancies can be methodologically addressed through:

• Antibody validation strategies:

  • Implement comprehensive specificity controls (peptide competition, phosphatase treatment)

  • Use multiple antibodies from different vendors/clones when possible

  • Include genetic approaches (CRISPR-mediated Thr789 mutation) as definitive controls

  • Apply the validated specificity tests shown to distinguish true signals (immunogen peptide blocking, phosphatase treatment)

• Cell context considerations:

  • Phosphorylation status may differ fundamentally between cell types

  • Adhesion state dramatically affects phosphorylation (adherent vs. suspension culture)

  • Cell density influences baseline phosphorylation through contact inhibition mechanisms

  • Standardize cell culture conditions when comparing between studies

• Technical refinements:

  • Enrich for membrane fractions to concentrate integrin proteins

  • Use phosphatase inhibitors consistently during sample preparation

  • Consider subcellular fractionation to distinguish membrane-associated vs. internalized pools

  • Apply the recommended membrane enrichment protocol (30 μg lysate) for optimal detection

• Temporal dynamics analysis:

  • Implement rigorous time-course experiments with standardized time points

  • Account for rapid phosphorylation/dephosphorylation cycles

  • Consider circadian or cell-cycle dependent fluctuations in baseline phosphorylation

• Integration of multiple methodologies:

  • Combine immunoblotting, immunofluorescence, and flow cytometry approaches

  • Validate key findings with phospho-proteomic mass spectrometry

  • Use cell-based ELISA for higher throughput quantitative analysis

By implementing these methodological refinements, researchers can resolve apparent contradictions and develop a more nuanced understanding of the context-dependent regulation of ITGB1 Thr789 phosphorylation.

What are the current methodological approaches for studying the interplay between ITGB1 Thr789 phosphorylation and other post-translational modifications?

Investigating the interplay between phosphorylation at Thr789 and other post-translational modifications (PTMs) of ITGB1 requires sophisticated methodological approaches:

• Multi-antibody detection strategies:

  • Sequential probing with antibodies against different modifications

  • Use multiplexed detection systems with spectrally distinct fluorophores

  • Implement Far-Western blotting to examine modification-dependent interactions

• Mass spectrometry-based approaches:

  • Enrich for ITGB1 through immunoprecipitation before MS analysis

  • Apply phospho-enrichment strategies (TiO₂, IMAC) for comprehensive phospho-mapping

  • Use targeted MS approaches for quantitative analysis of specific modification sites

  • Correlate with immunoblotting using phospho-ITGB1 (Thr789) antibody for validation

• Site-directed mutagenesis studies:

  • Generate phospho-mimetic (T789D/E) and phospho-deficient (T789A) mutants

  • Create combination mutants affecting multiple modification sites

  • Analyze functional consequences through cell adhesion, migration, and signaling assays

• PTM crosstalk analysis:

  • Examine how Thr789 phosphorylation affects nearby modifications

  • Study reciprocal regulation between phosphorylation and other PTMs (glycosylation, ubiquitination)

  • Investigate modification-dependent protein-protein interactions

• Temporal sequence determination:

  • Use kinetic studies to establish order of modification events

  • Apply specific kinase/modifying enzyme inhibitors to disrupt normal modification patterns

  • Correlate with functional outcomes using established cellular assays

These methodological approaches provide a framework for understanding the complex regulatory networks governing integrin function through combinatorial post-translational modifications, with potential implications for targeted therapeutic interventions in diseases characterized by dysregulated integrin signaling.

How can Phospho-ITGB1 (Thr789) antibody be used in translational cancer research?

Phospho-ITGB1 (Thr789) antibody offers significant potential in translational cancer research through these methodological approaches:

• Tissue microarray analysis:

  • Apply validated immunohistochemistry protocols (1:50 - 1:100 dilution) to patient samples

  • Correlate phosphorylation status with clinical parameters and patient outcomes

  • Compare primary tumors with metastatic lesions to examine phosphorylation during progression

• Drug response prediction:

  • Monitor Thr789 phosphorylation as a potential biomarker for response to targeted therapies

  • Examine changes in phosphorylation following treatment with anti-integrin therapeutics

  • Correlate with other markers of treatment resistance or sensitivity

• Combination with patient-derived models:

  • Analyze phosphorylation status in patient-derived xenografts and organoids

  • Test drug combinations targeting phosphorylation-dependent pathways

  • Use validated Western blot and immunofluorescence protocols optimized for these complex models

• Metastasis research applications:

  • Compare phosphorylation in circulating tumor cells vs. primary tumors

  • Examine integrin phosphorylation at various stages of the metastatic cascade

  • Correlate with markers of epithelial-mesenchymal transition and tumor cell plasticity

• Therapeutic target validation:

  • Use phospho-antibodies to monitor target engagement in early-phase clinical trials

  • Develop rational drug combinations based on phosphorylation-dependent vulnerabilities

  • Apply cell-based ELISA methods for higher throughput screening of patient samples

These approaches leverage the specificity and sensitivity of Phospho-ITGB1 (Thr789) antibody to advance understanding of integrin signaling in cancer progression and treatment response, potentially informing personalized medicine strategies.

What methodological considerations are important when using Phospho-ITGB1 (Thr789) antibody in 3D culture systems and organoids?

Applying Phospho-ITGB1 (Thr789) antibody to 3D culture systems and organoids presents unique challenges requiring specific methodological adaptations:

• Sample preparation optimization:

  • Develop specialized fixation protocols that preserve phospho-epitopes while allowing antibody penetration

  • Consider whole-mount staining for smaller organoids vs. sectioning for larger structures

  • Adapt clearing techniques (CLARITY, CUBIC) to enhance imaging depth while maintaining phospho-epitope integrity

• Imaging considerations:

  • Implement confocal or light-sheet microscopy for 3D visualization

  • Use optical sectioning to analyze phosphorylation patterns throughout the structure

  • Apply deconvolution algorithms to enhance signal resolution in dense tissues

• Validation strategies:

  • Include phosphatase-treated controls to verify phospho-specificity in 3D contexts

  • Use competing phosphopeptide controls to confirm antibody specificity

  • Compare with 2D cultures to establish baseline differences in phosphorylation patterns

• Signal quantification approaches:

  • Develop 3D image analysis workflows for phosphorylation quantification

  • Consider spatial distribution of phosphorylation (core vs. periphery of organoids)

  • Normalize to total ITGB1 distribution using sequential or multiplexed staining

• Experimental manipulation:

  • Apply ECM-modifying treatments to alter integrin engagement

  • Use microfluidic systems to create defined mechanical and biochemical gradients

  • Compare organoids derived from different tissue sources to examine context-dependent phosphorylation

These methodological considerations enable researchers to leverage the specificity of Phospho-ITGB1 (Thr789) antibody for investigating integrin signaling in physiologically relevant 3D systems, bridging the gap between traditional 2D culture and in vivo models.