Phospho-BCL2L1 (T47) Antibody

What is Phospho-BCL2L1 (T47) Antibody and what does it detect?

Phospho-BCL2L1 (T47) Antibody is a rabbit polyclonal antibody that specifically recognizes BCL2L1 (also known as Bcl-x or Bcl-XL) protein only when phosphorylated at threonine 47. This antibody detects endogenous levels of phosphorylated Bcl-x at the T47 site, which is located within amino acids 13-62 of the protein sequence. The antibody does not cross-react with non-phosphorylated forms of BCL2L1 or with other phosphorylation sites, making it a specific tool for studying this particular post-translational modification .

What research applications is Phospho-BCL2L1 (T47) Antibody validated for?

The antibody has been validated for multiple research applications with specific dilution recommendations:

These applications allow researchers to examine phosphorylation status of BCL2L1 at T47 in various experimental contexts, from protein expression levels to cellular localization studies .

What species reactivity has been confirmed for Phospho-BCL2L1 (T47) Antibody?

The antibody has been confirmed to react with human, mouse, and rat samples. This cross-reactivity makes it suitable for comparative studies across multiple model systems, enhancing translational research potential. When studying other species, validation experiments should be conducted prior to extensive research applications .

How should I optimize Western blot conditions for detecting phospho-BCL2L1 (T47)?

For optimal Western blot detection of phospho-BCL2L1 (T47):

• Sample preparation: Preserve phosphorylation status by including phosphatase inhibitors (e.g., sodium orthovanadate, sodium fluoride) in your lysis buffer.

• Gel selection: Use 10-12% polyacrylamide gels as BCL2L1 has a molecular weight of approximately 26 kDa.

• Transfer conditions: Transfer at 100V for 60-90 minutes using PVDF membranes for better retention of phosphorylated proteins.

• Blocking: Use 5% BSA in TBST rather than milk, as milk contains phosphatases that may reduce signal.

• Antibody dilution: Start with 1:1000 dilution in 5% BSA/TBST and optimize as needed.

• Detection: Enhanced chemiluminescence systems provide adequate sensitivity for this application.

• Controls: Include both phosphatase-treated negative controls and samples known to induce T47 phosphorylation as positive controls .

What are the recommended fixation and permeabilization procedures for immunofluorescence with Phospho-BCL2L1 (T47) Antibody?

For optimal immunofluorescence results:

• Fixation: 4% paraformaldehyde for 15 minutes at room temperature preserves phospho-epitopes better than methanol fixation.

• Permeabilization: 0.1-0.2% Triton X-100 in PBS for 10 minutes.

• Blocking: 1-2% BSA or 5-10% normal serum in PBS for 1 hour.

• Primary antibody: Apply Phospho-BCL2L1 (T47) antibody at 1:200-1:500 dilution overnight at 4°C.

• Washing: Perform 3-5 washes with PBS containing 0.05% Tween-20.

• Secondary antibody: Use fluorophore-conjugated anti-rabbit IgG at manufacturer's recommended dilution.

• Counterstaining: DAPI for nuclear visualization, with appropriate mounting medium to prevent photobleaching.

This protocol maintains the integrity of the phospho-specific epitope while providing clear subcellular localization information .

How can I validate the specificity of phospho-T47 signal in my experimental system?

Comprehensive validation strategies include:

• Phosphatase treatment: Treat duplicate samples with lambda phosphatase to demonstrate signal loss.

• Competing peptide assay: Pre-incubate antibody with phospho-T47 peptide to block specific binding.

• siRNA/CRISPR: Knockdown or knockout BCL2L1 to confirm signal specificity.

• Physiological regulation: Treat cells with stimuli known to modulate BCL2L1 phosphorylation.

• Site-directed mutagenesis: Generate T47A mutants that cannot be phosphorylated at this position.

• Multiple detection methods: Confirm findings using alternative techniques (e.g., mass spectrometry).

• Cross-antibody validation: Compare results with other validated phospho-T47 antibodies when available.

These approaches collectively provide strong evidence for signal specificity and reduce the risk of misinterpreting experimental results .

How does BCL2L1 phosphorylation at T47 differ from other phosphorylation sites in functional significance?

BCL2L1 undergoes phosphorylation at multiple sites with distinct functional consequences:

Unlike the well-characterized S62 phosphorylation by CDK1 that promotes apoptosis in response to DNA damage, T47 phosphorylation has less established functional consequences. Current research suggests it may modify protein-protein interactions with other BCL-2 family members, potentially altering the balance between pro- and anti-apoptotic functions .

What are common technical challenges when working with Phospho-BCL2L1 (T47) Antibody and how can they be addressed?

Common challenges and solutions include:

• High background signal:

  • Increase blocking time/concentration

  • Optimize antibody dilution (try more dilute preparations)

  • Use more stringent washing conditions

  • Try alternative blocking agents

• Weak or absent signal:

  • Ensure phosphorylation status is preserved (check phosphatase inhibitors)

  • Confirm appropriate stimulation conditions to induce T47 phosphorylation

  • Reduce exposure to phosphatases during sample handling

  • Consider antigen retrieval methods for IHC applications

  • Test different fixation methods that better preserve phospho-epitopes

• Multiple bands on Western blot:

  • BCL2L1 has multiple isoforms (Bcl-XL, Bcl-XS, Bcl-Xβ)

  • Post-translational modifications can create mobility shifts

  • Proteolytic cleavage during apoptosis creates fragments

  • Validate bands with appropriate positive and negative controls

• Inconsistent results between applications:

  • Different applications may require different optimization strategies

  • Phospho-epitopes may be differently accessible in various techniques

  • Consider using complementary approaches to confirm findings .

How can I distinguish between the different isoforms of BCL2L1 when using Phospho-BCL2L1 (T47) Antibody?

BCL2L1 exists in multiple isoforms with distinct molecular weights and functions:

• Bcl-XL (233 amino acids): The predominant anti-apoptotic isoform (~26 kDa)

• Bcl-XS (178 amino acids): Lacks amino acids 126-188, pro-apoptotic (~21 kDa)

• Bcl-Xβ: Less common isoform

When using Phospho-BCL2L1 (T47) Antibody:

• Run appropriate molecular weight markers

• Include recombinant protein standards of known isoforms

• Use isoform-specific siRNAs or expression constructs as controls

• Compare with total BCL2L1 antibodies that recognize all isoforms

• Note that T47 is present in both Bcl-XL and Bcl-XS isoforms

• For conclusive identification, consider using isoform-specific antibodies in parallel experiments or mass spectrometry analysis

The antibody will detect phosphorylated forms of any isoform containing the T47 site, so molecular weight discrimination is crucial for proper interpretation .

How does phosphorylation of BCL2L1 at T47 contribute to cancer development and therapeutic resistance?

While the specific role of T47 phosphorylation remains under investigation, BCL2L1 is implicated in cancer through several mechanisms:

• Amplification: BCL2L1 is amplified in 18.4% of gastric cancer cases (19/103 samples), promoting tumor cell survival .

• Therapeutic resistance:

  • BCL2L1 overexpression contributes to resistance against B-RAF V600E inhibitors in melanoma

  • Phosphorylation status may modulate interaction with pro-apoptotic proteins like BAX and BAK

  • Altering phosphorylation can potentially sensitize resistant cells to therapy

• Regulation mechanism:

  • Phosphorylation at different sites affects BCL2L1's anti-apoptotic function

  • T47 phosphorylation may represent a regulatory mechanism distinct from other sites

  • Understanding site-specific phosphorylation could reveal new therapeutic approaches

Research suggests that targeting BCL2L1-dependent pathways, potentially in phosphorylation-specific manners, could overcome therapeutic resistance in multiple cancer types .

What experimental approaches can assess the functional consequences of BCL2L1 phosphorylation at T47?

To investigate functional consequences of T47 phosphorylation:

• Site-directed mutagenesis studies:

  • Generate T47A (phospho-deficient) and T47D/E (phospho-mimetic) mutants

  • Compare their effects on apoptosis regulation in cellular models

• Kinase/phosphatase identification:

  • Perform kinase prediction analysis based on sequence context

  • Use kinase/phosphatase inhibitor screens to identify regulatory enzymes

  • Validate with in vitro kinase assays and mass spectrometry

• Protein-protein interaction studies:

  • Compare interaction partners between wild-type and phospho-mutants using co-immunoprecipitation

  • Utilize proximity ligation assays to examine interactions in intact cells

  • Perform structural studies to understand conformational changes induced by phosphorylation

• Cellular response assays:

  • Examine effects on cell survival, apoptosis sensitivity, and drug resistance

  • Combine with other BCL-2 family protein manipulations to understand network effects

  • Correlate phosphorylation status with cellular outcomes after therapeutic challenges

How can Phospho-BCL2L1 (T47) Antibody be used in combination with BCL-2 family inhibitors for cancer research?

Phospho-BCL2L1 (T47) Antibody offers valuable research applications when studying BCL-2 family inhibitors:

• Biomarker development:

  • Monitor T47 phosphorylation status before and after treatment with BCL-2 family inhibitors like ABT-737

  • Correlate phosphorylation levels with treatment response and resistance development

• Mechanistic studies:

  • Examine whether BCL-2 family inhibitors alter phosphorylation patterns of BCL2L1

  • Investigate if T47 phosphorylation status predicts sensitivity to specific inhibitors

• Combination therapy research:

  • Study whether modulating kinases/phosphatases that regulate T47 phosphorylation enhances BCL-2 inhibitor efficacy

  • Analyze synergistic effects between phosphorylation-targeting approaches and direct BCL-2 family inhibition

• Resistance mechanism investigation:

  • Compare T47 phosphorylation status between sensitive and resistant cell populations

  • Determine if phosphorylation changes correlate with acquired resistance

Research has shown that BCL-2 family inhibitors like ABT-737 can synergize with other treatments in BCL2L1-amplified cancer models, and phosphorylation status may be a critical determinant of this synergy .

What are the optimal storage conditions and shelf life for Phospho-BCL2L1 (T47) Antibody?

For maximum stability and performance:

• Storage temperature: Store at -20°C or -80°C

• Formulation: Typically supplied in PBS containing 50% glycerol, 0.5% BSA, and 0.02% sodium azide

• Aliquoting: Prepare small working aliquots to avoid repeated freeze-thaw cycles

• Shelf life: Generally stable for up to 1 year from receipt when stored properly

• Working solution: Diluted antibody should be prepared fresh and used within 24 hours

• Transportation: Can be shipped at ambient temperature but should be stored frozen upon receipt

• Quality indicators: Monitor for precipitation, microbial contamination, or loss of activity

Proper storage is essential for maintaining phospho-epitope recognition, as phospho-specific antibodies can be particularly sensitive to storage conditions .

What quality control measures ensure the specificity and reproducibility of Phospho-BCL2L1 (T47) Antibody?

Standard quality control procedures include:

• Immunogen design and validation:

  • Use of synthetic phosphopeptide derived from the region surrounding T47

  • Confirmation of sequence conservation across target species

• Purification methods:

  • Affinity purification using epitope-specific immunogen

  • Purity assessment by SDS-PAGE (typically >95% purity)

• Specificity testing:

  • Western blot analysis with phosphorylated and non-phosphorylated proteins

  • Peptide competition assays with phospho and non-phospho peptides

  • Phosphatase treatment to confirm phospho-specificity

• Cross-reactivity assessment:

  • Testing against related phosphorylation sites

  • Evaluation across multiple species (human, mouse, rat)

• Batch-to-batch reproducibility:

  • Consistent production methods and quality checks

  • Comparison to reference standards for each new lot

These measures ensure that the antibody consistently and specifically recognizes BCL2L1 phosphorylated at T47 across experiments and applications .

How can I determine the most appropriate negative and positive controls for Phospho-BCL2L1 (T47) Antibody experiments?

Establishing proper controls is critical for interpreting phospho-specific antibody results:

Positive controls:

• Cell lines with known BCL2L1 T47 phosphorylation (e.g., certain cancer cell lines)

• Tissues with documented BCL2L1 expression and phosphorylation (e.g., RAT-MUSCLE has been validated)

• Cells treated with agents that induce BCL2L1 phosphorylation

• Recombinant phosphorylated BCL2L1 protein (if available)

Negative controls:

• Samples treated with lambda phosphatase to remove phosphate groups

• Cell lines with BCL2L1 knockdown or knockout

• T47A mutant BCL2L1 expression systems

• Tissues/cells known to lack BCL2L1 expression

Technical controls:

• Primary antibody omission control

• Isotype control (rabbit IgG at matching concentration)

• Peptide competition control with phospho-T47 peptide

• Secondary antibody-only control

Including these controls systematically validates experimental findings and provides confidence in the specificity of observed signals .

How can Phospho-BCL2L1 (T47) Antibody be integrated into high-throughput screening approaches for cancer therapeutics?

Integrating Phospho-BCL2L1 (T47) Antibody into high-throughput screening enables:

• Phosphorylation-based drug screening:

  • Develop ELISA or AlphaScreen assays using the antibody to detect T47 phosphorylation

  • Screen compound libraries for molecules that modulate this specific phosphorylation

  • Identify kinase or phosphatase inhibitors that specifically affect T47 phosphorylation

• Automated microscopy platforms:

  • Utilize immunofluorescence applications (1:200-1:1000 dilution) in cell-based screens

  • Quantify nuclear versus cytoplasmic distribution of phosphorylated BCL2L1

  • Correlate phosphorylation changes with cellular phenotypes

• Multiplex analysis systems:

  • Combine with other apoptosis markers in automated Western blot systems

  • Develop bead-based assays for simultaneous detection of multiple phosphorylation sites

  • Create flow cytometry panels to correlate phosphorylation with cell cycle status

• Patient-derived xenograft (PDX) models:

  • Screen therapies for effects on T47 phosphorylation in PDX models

  • Correlate phosphorylation status with treatment response

  • Identify potential biomarkers for patient stratification

What are the most recent discoveries about the relationship between BCL2L1 phosphorylation and mitochondrial dynamics in cancer cells?

Recent research indicates complex relationships between BCL2L1 phosphorylation and mitochondrial function:

• Phosphorylation-dependent localization:

  • Site-specific phosphorylation can alter BCL2L1 subcellular localization

  • T47 phosphorylation may influence mitochondrial outer membrane association

• Interaction with mitochondrial fission/fusion machinery:

  • Phosphorylated BCL2L1 may differentially interact with proteins like DRP1 and MFN1/2

  • These interactions potentially modify mitochondrial network dynamics

• Cell cycle-dependent regulation:

  • Phosphorylation at Ser-49 fluctuates during cell cycle progression

  • Appears during S and G2 phases

  • Disappears during prometaphase, metaphase and early anaphase

  • Reappears during telophase and cytokinesis

• Links to metabolic reprogramming:

  • BCL2L1 phosphorylation status may influence metabolic pathways beyond apoptosis regulation

  • Growing evidence connects BCL-2 family proteins to mitochondrial metabolism

  • Phosphorylation could represent a switch between metabolic and apoptotic functions

These discoveries suggest that BCL2L1 phosphorylation serves as a regulatory mechanism connecting cell survival decisions with mitochondrial dynamics and metabolism .

How does BCL2L1 phosphorylation at T47 compare with phosphorylation of other BCL-2 family proteins in terms of functional outcomes?

Comparative analysis reveals distinctive patterns across BCL-2 family phosphorylation sites:

Unlike BCL2 phosphorylation at Ser70 that enhances its anti-apoptotic function, the functional consequences of BCL2L1 T47 phosphorylation remain less defined. The site-specific phosphorylation of different BCL-2 family members creates a complex regulatory network that fine-tunes apoptotic thresholds in response to various cellular stresses and signaling pathways.