Phospho-MYF5 (S49) Antibody

What is MYF5 and what is the significance of its phosphorylation at Serine 49?

MYF5 (Myogenic Factor 5) is a member of the myogenic basic helix-loop-helix family of transcription factors that plays a critical role in activating the muscle differentiation program . Known alternatively as bHLHc2 or Class C basic helix-loop-helix protein 2, MYF5 has a molecular weight of approximately 28 kDa .

Phosphorylation at Serine 49 represents a key post-translational modification that regulates MYF5's transcriptional activity. This specific phosphorylation event likely modulates protein-protein interactions, DNA binding affinity, and potentially influences myoblast determination and differentiation timing. Methodologically, studying this phosphorylation requires phospho-specific antibodies that exclusively recognize this modified form of the protein.

What applications is Phospho-MYF5 (S49) Antibody suitable for?

Phospho-MYF5 (S49) antibody has been validated for multiple research applications with specific optimal dilution ranges:

For optimal results, researchers should validate these dilutions in their specific experimental systems, as sensitivity may vary between tissue types and experimental conditions.

What are the specificity characteristics of Phospho-MYF5 (S49) Antibody?

The antibody specifically detects endogenous levels of MYF5 protein only when phosphorylated at Serine 49 . This high specificity is achieved through:

• Immunization with a synthetic phosphopeptide spanning amino acids 21-70 of human MYF5, centered around the phospho-Ser49 site

• Affinity purification using epitope-specific immunogen chromatography

• Validation through blocking peptide experiments, where the phospho-peptide effectively eliminates antibody binding in Western blot analysis

When performing validation experiments, researchers should include appropriate controls such as:

• Dephosphorylated samples (phosphatase-treated)

• Blocking with immunizing phosphopeptide

• Comparison with total MYF5 antibody detection

What are the optimal sample preparation protocols for preserving MYF5 phosphorylation status?

Preserving phosphorylation state is critical when working with phospho-specific antibodies. Recommended methodological approach:

• Lysis buffer composition:

  • Standard RIPA or NP-40 buffer supplemented with:

  • Phosphatase inhibitors (10mM sodium fluoride, 1mM sodium orthovanadate, 10mM β-glycerophosphate)

  • Protease inhibitors (1mM PMSF, 1μg/ml leupeptin, 1μg/ml aprotinin)

  • 1mM DTT or 5mM β-mercaptoethanol

• Tissue/cell handling:

  • Process samples immediately after collection

  • Flash freeze in liquid nitrogen if immediate processing isn't possible

  • Keep samples on ice during all processing steps

  • Avoid repeated freeze-thaw cycles

• Special considerations:

  • For muscle tissue, use specialized preservation techniques to maintain phospho-epitopes

  • Consider phosphatase activity in different tissue types when determining inhibitor concentrations

How can I optimize Western Blot protocols for Phospho-MYF5 (S49) detection?

Optimizing Western blot for phospho-epitope detection requires careful attention to several parameters:

Troubleshooting tips:

• If background is high, increase washing steps and decrease antibody concentration

• If signal is weak, optimize antigen retrieval or increase antibody concentration

• Consider using phosphatase inhibitors in all buffers throughout the procedure

What are the recommended antigen retrieval methods for IHC with Phospho-MYF5 (S49) Antibody?

Effective epitope unmasking is critical for phospho-epitope detection in fixed tissues:

• Heat-induced epitope retrieval (HIER):

  • High-pressure and temperature Tris-EDTA, pH 8.0 has been validated

  • 10mM citrate buffer (pH 6.0) for 20 minutes at 95-100°C is an alternative

  • Allow gradual cooling to room temperature (20 minutes)

• Protocol optimization parameters:

  • Fixation: 10% neutral buffered formalin for 24h maximum

  • Section thickness: 4-5μm optimal for signal penetration

  • Primary antibody dilution: Start with 1:100 in PBS with 1% BSA

  • Incubation: Overnight at 4°C in humidity chamber

• Controls:

  • Peptide competition with immunizing phosphopeptide

  • Lambda phosphatase-treated sections as negative control

  • Known positive tissue (human breast cancer tissue has been validated)

How can I use Phospho-MYF5 (S49) Antibody to investigate temporal dynamics of muscle differentiation?

Investigating the temporal phosphorylation pattern requires careful experimental design:

• Time-course experimental setup:

  • Collect samples at defined intervals during differentiation (0h, 6h, 12h, 24h, 48h, 72h)

  • Use both C2C12 mouse myoblasts and primary human myoblasts for comparative analysis

  • Maintain parallel cultures for immunofluorescence and protein extraction

• Quantitative analysis methods:

  • Western blot with normalization to total MYF5 levels

  • Ratio analysis of phospho-MYF5/total MYF5 during differentiation

  • Immunofluorescence intensity quantification using standardized exposure settings

• Data interpretation framework:

  Differentiation Stage	Expected Phospho-MYF5 (S49) Pattern	Biological Significance
  Proliferating myoblasts	Low-moderate levels	Maintenance of progenitor state
  Early differentiation (0-24h)	Rapid increase	Activation of myogenic program
  Mid differentiation (24-48h)	Peak levels	Active transcriptional regulation
  Late differentiation (48-72h)	Gradual decrease	Transition to other MRFs (MyoD, myogenin)

What are the known kinases that phosphorylate MYF5 at Serine 49, and how can this be experimentally verified?

While the search results don't specifically identify the kinases responsible for MYF5 S49 phosphorylation, researchers can employ the following methodological approach:

• In silico analysis:

  • Kinase prediction algorithms suggest S49 is within consensus motifs for several kinases:

    • p38 MAPK family members

    • Glycogen synthase kinase 3 (GSK3)

    • Casein kinase II (CKII)

• Experimental validation methods:

  • Kinase inhibitor studies:

    • Treat cells with specific kinase inhibitors and assess S49 phosphorylation

    • Example inhibitor panel: SB203580 (p38), LY294002 (PI3K/Akt), GSK3 inhibitor IX

  • In vitro kinase assays:

    • Express recombinant MYF5 (wild-type and S49A mutant)

    • Perform kinase reactions with purified candidate kinases

    • Detect phosphorylation by autoradiography or Phospho-MYF5 (S49) Antibody

  • Genetic approaches:

    • siRNA/shRNA knockdown of candidate kinases

    • CRISPR-Cas9 knockout/knockin studies

    • Overexpression of constitutively active kinase mutants

• Validation controls:

  • Site-directed mutagenesis (S49A) as negative control

  • Phosphatase treatment of samples

  • Peptide competition assays

How does phosphorylation at Serine 49 affect MYF5's transcriptional activity and protein interactions?

Investigating the functional consequences of S49 phosphorylation requires specialized methodological approaches:

• Transcriptional activity assessment:

  • Reporter gene assays:

    • Construct luciferase reporters containing MYF5-responsive elements

    • Co-transfect with wild-type MYF5, S49A (non-phosphorylatable), or S49D/E (phosphomimetic) mutants

    • Measure relative luciferase activity under differentiation conditions

  • ChIP-seq analysis:

    • Perform chromatin immunoprecipitation using Phospho-MYF5 (S49) Antibody

    • Compare binding profiles of total MYF5 versus phosphorylated MYF5

    • Identify differential binding sites that depend on phosphorylation status

• Protein interaction studies:

  • Co-immunoprecipitation:

    • Use Phospho-MYF5 (S49) Antibody to pull down phosphorylated form

    • Identify differential binding partners by mass spectrometry

    • Validate key interactions by reciprocal co-IP

  • Proximity ligation assay (PLA):

    • Detect in situ interactions between phosphorylated MYF5 and candidate partners

    • Compare interaction profiles between wild-type and phospho-mutants

• Functional impacts on muscle differentiation:

  Parameter	Wild-type MYF5	S49A Mutant	S49D/E Mutant	Methodology
  Myoblast proliferation	Baseline	Decreased	Increased	EdU incorporation assay
  Differentiation timing	Normal	Delayed	Accelerated	Myosin heavy chain expression timeline
  Fusion index	Normal	Reduced	Enhanced	Multinucleated myotube quantification
  Target gene expression	Baseline	Altered profile	Altered profile	RT-qPCR array of myogenic genes

What are common causes of non-specific background when using Phospho-MYF5 (S49) Antibody and how can they be addressed?

Non-specific background is a common challenge with phospho-specific antibodies. Methodological solutions include:

• Antibody-specific considerations:

  • Verify concentration is within recommended range (WB: 1:500-1:2000, IHC: 1:100-1:300)

  • Pre-absorb antibody with non-phosphorylated peptide to remove non-phospho-specific antibodies

  • Always include peptide competition controls with immunizing phosphopeptide

• Western blot optimization:

  • Use 5% BSA instead of milk for blocking and antibody dilution

  • Extend washing steps (5 × 10 minutes in TBST)

  • Add 0.1% Tween-20 to antibody dilution buffer to reduce hydrophobic interactions

  • Pre-run gel to remove excess SDS and ammonium persulfate

• IHC/IF optimization:

  • Increase blocking time (2 hours room temperature or overnight at 4°C)

  • Use blocking with 10% normal goat serum + 1% BSA

  • Include 0.3% Triton X-100 in antibody diluent for better penetration

  • Extend washing steps between antibody incubations

• Sample-related improvements:

  • Ensure complete protein denaturation for Western blot

  • Optimize fixation time for IHC/IF (overfixation masks epitopes)

  • Include phosphatase inhibitors in all buffers throughout sample preparation

How can I validate the specificity of Phospho-MYF5 (S49) Antibody in my experimental system?

Comprehensive validation should include multiple orthogonal approaches:

• Antibody-specific controls:

  • Peptide competition with phosphorylated vs. non-phosphorylated peptides

  • Western blot showing a single band at ~28kDa

  • Lambda phosphatase treatment to demonstrate phospho-specificity

  • Comparison with other anti-MYF5 antibodies that detect total protein

• Genetic approaches:

  • CRISPR/Cas9 knockout of MYF5 (should eliminate signal)

  • Site-directed mutagenesis (S49A) to create non-phosphorylatable mutant

  • MYF5 siRNA knockdown (should reduce signal proportionally)

• Stimulation experiments:

  • Treat cells with phosphatase inhibitors (should increase signal)

  • Create conditions that modulate the responsible kinase activity

  • Compare signal in proliferating vs. differentiating myoblasts

• Technical validation:

  • Secondary antibody-only control

  • IgG isotype control to assess non-specific binding

  • Multiple detection methods (HRP, fluorescence)

  • Cross-validation across applications (WB, IHC, IF)

What factors might cause variability in Phospho-MYF5 (S49) detection between experiments?

Understanding sources of variability helps design more reproducible experiments:

How can Phospho-MYF5 (S49) Antibody be utilized in high-throughput screening applications?

Adapting this antibody for high-throughput applications requires optimization:

• Microplate-based assays:

  • In-cell ELISA in 96/384-well format (1:10000 dilution optimal)

  • High-content imaging systems for automated IF analysis

  • Multiplex with total MYF5 antibody using different fluorophores

• Methodology considerations:

  • Automated liquid handling systems for consistent antibody delivery

  • Signal normalization to total protein or housekeeping markers

  • Z-factor optimization for assay validation

  • Positive and negative controls on each plate

• Screening applications:

  • Kinase inhibitor libraries to identify S49 regulatory pathways

  • Small molecule modulators of muscle differentiation

  • siRNA/CRISPR libraries targeting muscle regulatory networks

What are the considerations for using Phospho-MYF5 (S49) Antibody in single-cell analysis techniques?

Single-cell techniques require special optimization:

• Flow cytometry/FACS:

  • Fixation: 2% paraformaldehyde for 10 minutes

  • Permeabilization: 90% ice-cold methanol or saponin-based buffer

  • Primary antibody: 1:50-1:200 dilution range

  • Compensation: Critical when multiplexing with other antibodies

  • Controls: Isotype, secondary-only, and phosphatase-treated cells

• Single-cell protein analysis:

  • Microfluidic western blotting requires high antibody specificity

  • Mass cytometry (CyTOF) requires metal-conjugated antibody

  • Single-cell proteomics demands rigorous antibody validation

• Spatial analysis in tissues:

  • Multiplex IF using spectral unmixing and Phospho-MYF5 (S49) Antibody

  • Combination with RNAscope for simultaneous protein/mRNA detection

  • Laser capture microdissection followed by protein analysis

The integration of these advanced techniques allows researchers to map the heterogeneity of MYF5 phosphorylation status across individual cells during muscle development and regeneration.