SPBC15C4.06c Antibody

What is SPBC15C4.06c and why is it studied in fission yeast research?

SPBC15C4.06c (also known as SPBC21H7.01c) is an uncharacterized RING finger membrane protein found in Schizosaccharomyces pombe (strain 972 / ATCC 24843), commonly known as fission yeast. This protein is of interest because it is a single-pass membrane protein located in both the vacuole membrane and cell membrane, suggesting potential roles in membrane trafficking, protein degradation, or signaling pathways . Studies in S. pombe are particularly valuable as this model organism allows researchers to investigate fundamental cellular processes like cell cycle regulation, chronological lifespan, and response to nutritional cues, which have parallels in higher eukaryotes including humans .

What are the optimal storage conditions for SPBC15C4.06c antibody?

SPBC15C4.06c antibody should be stored at -20°C or -80°C upon receipt. Repeated freeze-thaw cycles should be avoided as this can degrade antibody quality and reduce binding efficacy . For working solutions, the antibody is typically maintained in a buffer containing 50% glycerol, 0.01M PBS at pH 7.4, with 0.03% Proclin 300 as a preservative. This formulation helps maintain antibody stability during short-term storage at 2-8°C (for up to one month) when handled under sterile conditions. For long-term storage of reconstituted antibody, aliquoting and returning to -20°C or -70°C is recommended to prevent protein degradation from multiple freeze-thaw cycles.

What experimental applications have been validated for SPBC15C4.06c antibody?

The SPBC15C4.06c antibody has been validated for specific research applications including Enzyme-Linked Immunosorbent Assay (ELISA) and Western Blotting (WB) . These techniques allow researchers to detect and quantify the SPBC15C4.06c protein in various experimental contexts. Western blotting applications typically involve protein extraction using methods such as the trichloroacetic acid (TCA) precipitation, followed by SDS-PAGE separation and transfer to nitrocellulose membranes . While not explicitly validated, this antibody may also potentially be useful in other immunochemical applications common in S. pombe research, such as immunoprecipitation for protein-protein interaction studies or immunofluorescence for subcellular localization, though optimization would be required.

How should researchers determine the appropriate working dilution for SPBC15C4.06c antibody in Western blot applications?

Determining the optimal working dilution for SPBC15C4.06c antibody requires systematic titration experiments. Researchers should:

• Begin with a dilution range based on manufacturer recommendations (typically 1:500 to 1:5000 for polyclonal antibodies)

• Perform Western blots using identical protein samples across multiple dilutions

• Evaluate signal-to-noise ratio at each dilution

• Select the dilution that provides clear specific binding with minimal background

Critical controls should include:

• Positive control (lysate from wild-type S. pombe expressing SPBC15C4.06c)

• Negative control (lysate from SPBC15C4.06c deletion mutant if available)

• Secondary antibody-only control to assess non-specific binding

The optimal procedure for protein extraction from S. pombe involves TCA precipitation methods, which have been shown to effectively preserve protein integrity for subsequent immunoblot analysis . Each new lot of antibody should undergo validation to account for potential lot-to-lot variations in specificity and sensitivity.

How can researchers utilize SPBC15C4.06c antibody in studies of protein degradation pathways in S. pombe?

SPBC15C4.06c antibody can be instrumental in investigating protein degradation pathways in S. pombe, particularly given the protein's RING finger domain (which often functions in ubiquitination) and its membrane localization. For comprehensive studies of protein degradation:

• Proteasomal degradation studies: Monitor SPBC15C4.06c protein levels in wild-type versus proteasome-deficient strains (e.g., mts3-1 temperature-sensitive mutants) using the antibody in Western blot analysis .

• Autophagy-related investigations: Compare SPBC15C4.06c protein levels in wild-type versus autophagy-deficient strains (e.g., Δatg8) under nitrogen starvation conditions, which induce the G0 quiescent state .

• Time-course experiments: Track SPBC15C4.06c protein levels during transition from proliferation to quiescence using the antibody, collecting samples at defined intervals after nitrogen removal.

• Co-immunoprecipitation studies: Use the antibody to identify SPBC15C4.06c-interacting proteins, particularly those involved in membrane protein trafficking or degradation.

A comprehensive experimental approach would involve both genomic and proteomic analyses, where Western blotting with the SPBC15C4.06c antibody would be complemented by mass spectrometry techniques to identify post-translational modifications and interacting partners .

What are the critical considerations when using SPBC15C4.06c antibody for immunoprecipitation studies in membrane protein research?

When using SPBC15C4.06c antibody for immunoprecipitation of this membrane protein, researchers must address several technical challenges:

• Membrane protein solubilization: Given that SPBC15C4.06c is a membrane-associated protein, effective solubilization requires careful selection of detergents. Consider:

  Detergent	Concentration	Advantages	Limitations
  Digitonin	0.5-1%	Maintains protein-protein interactions	Less efficient extraction
  CHAPS	0.5-1%	Gentle, preserves functionality	Moderate solubilization
  Triton X-100	0.1-0.5%	Efficient extraction	May disrupt some interactions
  NP-40	0.1-0.5%	Good for membrane proteins	Similar to Triton X-100

• Antibody immobilization strategy:

  • Direct coupling to beads using crosslinkers

  • Protein A/G beads for IgG capture

  • Pre-clearing lysates to reduce non-specific binding

• Validation controls:

  • Input control (10% of starting material)

  • Isotype control immunoprecipitation

  • IP from SPBC15C4.06c deletion strain (if available)

• Sequential solubilization: Consider a two-step solubilization protocol to separately analyze peripheral and integral membrane protein interactions .

For downstream analysis of immunoprecipitated samples, techniques such as LC-MS/MS can be employed as described in protocols for studying S. pombe protein complexes, with appropriate modifications for membrane proteins .

How can researchers address epitope masking issues when SPBC15C4.06c is part of a protein complex?

Epitope masking can significantly impact the detection of SPBC15C4.06c when it's engaged in protein-protein interactions or complexes. To overcome this challenge:

• Alternative sample preparation approaches:

  • Adjust detergent type and concentration to balance complex preservation and epitope exposure

  • Test multiple lysis buffers with varying salt concentrations (150-500 mM NaCl)

  • Evaluate mild denaturants (0.1% SDS or 2M urea) that may expose epitopes without completely disrupting relevant interactions

• Protein complex dissociation techniques:

  • Heat samples at different temperatures (37°C, 50°C, 65°C, 95°C)

  • Test reducing agent concentrations (5mM to 100mM DTT)

  • Consider mild sonication or freeze-thaw cycles

• Epitope retrieval methods:

  • For fixed samples in localization studies, evaluate different antigen retrieval buffers (citrate, EDTA, or Tris-based)

  • Test enzymatic treatments (e.g., proteinase K at very low concentrations) that might expose epitopes

• Alternative detection strategies:

  • Use tagged versions of SPBC15C4.06c (e.g., GFP, FLAG) that may provide epitopes accessible regardless of complex formation

  • Consider native vs. denaturing conditions for different experimental approaches

For comprehensive proteomics studies, researchers can employ the techniques used in whole proteome analysis of S. pombe, where proteins are extracted, separated by SDS-PAGE, in-gel-digested, and analyzed with LC-MS/MS . This approach can identify SPBC15C4.06c-containing complexes even when antibody detection is suboptimal.

What methodologies can resolve conflicting SPBC15C4.06c localization data between antibody-based and fluorescent protein fusion approaches?

When faced with discrepancies between SPBC15C4.06c localization determined by antibody immunofluorescence versus fluorescent protein fusions, researchers should implement the following strategy:

• Validate both approaches independently:

  • For antibody staining: Test specificity on SPBC15C4.06c deletion strains; perform blocking peptide controls

  • For fusion proteins: Create both N- and C-terminal fusions to assess whether tag position affects localization

  • Verify fusion protein functionality through complementation of phenotypes in deletion strains

• Employ multiple independent techniques:

  • Subcellular fractionation followed by Western blotting with SPBC15C4.06c antibody

  • Electron microscopy with immunogold labeling

  • Proximity labeling approaches (BioID or APEX) to confirm local protein environment

  • Co-localization with established compartment markers

• Address temporal and condition-dependent localization:

  • Monitor localization under different growth conditions (log phase, stationary phase, nitrogen starvation)

  • Perform time-course experiments during cell cycle progression

  • Evaluate localization after various stress treatments

  • Examine temperature-dependent localization changes in wild-type and relevant mutants

• Quantitative assessment:

  • Use digital image analysis to quantify co-localization coefficients with established markers

  • Perform line-scan analysis across cellular compartments

  • Document the percentage of cells showing each localization pattern

The subcellular localization data (vacuole membrane and cell membrane) should be carefully verified using these approaches, as dual localization may represent distinct functional pools of the protein or trafficking intermediates.

How can SPBC15C4.06c antibody be incorporated into studies on chronological lifespan in S. pombe?

SPBC15C4.06c antibody can be leveraged in chronological lifespan studies by monitoring protein expression and modification throughout the aging process. Given that proteasome function and autophagy are critical for chronological lifespan , and that SPBC15C4.06c is a membrane protein potentially involved in these pathways, the following integrated approach is recommended:

• Temporal expression analysis:

  • Monitor SPBC15C4.06c protein levels at defined intervals during chronological aging (days 1, 3, 7, 14, 21, etc.)

  • Compare expression in wild-type versus long-lived or short-lived mutants

  • Track potential post-translational modifications using gel-shift analysis and phospho-specific staining

• Genetic interaction studies:

  • Create SPBC15C4.06c deletion or overexpression strains

  • Cross with mutants affecting proteasome function (e.g., mts3-1) or autophagy (e.g., Δatg8)

  • Determine epistatic relationships by measuring chronological lifespan and using the antibody to track protein markers of relevant pathways

• Nutritional response integration:

  • Examine SPBC15C4.06c expression under different nutritional conditions that affect lifespan

  • Compare protein levels during growth in complete medium versus minimal medium

  • Monitor changes during nitrogen starvation-induced G0 quiescence

• Stress response correlation:

  • Study SPBC15C4.06c levels during oxidative, osmotic, or heat stress

  • Determine if protein levels correlate with stress resistance and longevity

  • Assess protein stability under stress conditions using cycloheximide chase experiments

This multifaceted approach integrates the SPBC15C4.06c antibody into the broader context of aging research in S. pombe, connecting membrane protein dynamics to established longevity pathways.

What considerations should researchers take when designing phospho-specific antibodies for SPBC15C4.06c post-translational modification studies?

Designing phospho-specific antibodies for SPBC15C4.06c requires careful planning and validation. The following methodology is recommended:

• Phosphorylation site prediction and selection:

  • Use bioinformatic tools (NetPhos, GPS, PhosphoSitePlus) to predict likely phosphorylation sites

  • Prioritize sites that are:

    • Conserved across Schizosaccharomyces species

    • Located in functional domains (especially the RING finger domain)

    • Predicted targets of known S. pombe kinases

    • Accessible based on protein structure predictions

• Phosphopeptide design considerations:

  • Generate synthetic phosphopeptides spanning 10-15 amino acids around the phosphorylation site

  • Include a C-terminal cysteine for conjugation if not naturally present

  • Consider designing multiple peptides with different lengths to optimize epitope presentation

  • Create both phosphorylated and non-phosphorylated versions of each peptide

• Validation strategy:

  • Test antibody specificity using:

    • Peptide competition assays with phosphorylated and non-phosphorylated peptides

    • Western blots comparing wild-type extracts versus phosphatase-treated samples

    • Samples from cells with mutations at the putative phosphorylation sites

    • Kinase inhibitor treatments if the relevant kinase is known

• Experimental application guideline:

  • Enrich phosphoproteins using:

    • Phosphoprotein enrichment columns

    • Immunoprecipitation with the standard SPBC15C4.06c antibody followed by phospho-specific detection

    • IMAC (Immobilized Metal Affinity Chromatography) for global phosphoprotein enrichment

The integration of phospho-specific antibodies with traditional proteomics approaches, such as those used in the analysis of S. pombe , will provide valuable insights into the regulation of SPBC15C4.06c through post-translational modifications.

How can researchers integrate SPBC15C4.06c antibody detection with omics approaches to understand its function in membrane dynamics?

To comprehensively understand SPBC15C4.06c's role in membrane dynamics, researchers should integrate antibody-based detection with multiple omics approaches:

• Integrative proteomics workflow:

  • Immunoprecipitate SPBC15C4.06c and analyze interacting partners via LC-MS/MS

  • Compare protein interaction networks under different conditions (e.g., normal growth vs. stress)

  • Complement with proximity labeling methods (BioID, APEX) to capture transient interactions

  • Apply quantitative proteomics (SILAC, TMT) to measure changes in the membrane proteome between wild-type and SPBC15C4.06c mutants

• Lipidomics integration:

  • Analyze changes in membrane lipid composition in SPBC15C4.06c mutants

  • Assess correlation between protein levels (detected by antibody) and specific lipid species

  • Investigate potential lipid-binding properties of SPBC15C4.06c

• Transcriptomics correlation:

  • Identify genes whose expression correlates with SPBC15C4.06c protein levels across conditions

  • Compare transcriptome changes in SPBC15C4.06c deletion or overexpression strains

  • Construct gene regulatory networks to position SPBC15C4.06c in cellular pathways

• Metabolomics connection:

  • Apply established S. pombe metabolite analysis methods to identify metabolic changes associated with SPBC15C4.06c function

  • Focus particularly on membrane-related metabolites (sphingolipids, sterols, phospholipids)

  • Correlate metabolic profiles with protein abundance in different genetic backgrounds

This multi-omics approach should be complemented with imaging techniques to visualize membrane dynamics, creating a comprehensive understanding of SPBC15C4.06c function.

What are the systematic approaches to troubleshoot non-specific binding of SPBC15C4.06c antibody in Western blot applications?

When encountering non-specific binding with SPBC15C4.06c antibody in Western blot applications, researchers should implement the following systematic troubleshooting approach:

• Blocking optimization:

  • Test different blocking agents:

    • 5% non-fat dry milk in TBST or PBST

    • 3-5% BSA in TBST or PBST

    • Commercial blocking buffers with different formulations

  • Optimize blocking time (1-16 hours) and temperature (room temperature vs. 4°C)

• Antibody dilution and incubation conditions:

  • Test serial dilutions of primary antibody (e.g., 1:500, 1:1000, 1:2000, 1:5000)

  • Compare overnight incubation at 4°C versus shorter incubations (1-4 hours) at room temperature

  • Add 0.1-0.5% Tween-20 or 0.1% Triton X-100 to antibody diluent to reduce hydrophobic interactions

  • Consider adding 1-5% of blocking agent to antibody diluent

• Washing procedure refinement:

  • Increase wash buffer volume and number of washes (5-6 washes of 10 minutes each)

  • Optimize detergent concentration in wash buffer (0.05-0.3% Tween-20)

  • Test different wash buffer compositions (TBS vs. PBS based)

• Sample preparation modifications:

  • Compare different protein extraction methods for S. pombe (TCA precipitation versus mechanical disruption)

  • Test different sample buffer compositions and reducing agent concentrations

  • Evaluate fresh versus frozen samples for potential degradation products

• Advanced validation methods:

  • Perform peptide competition assays using the immunogen peptide

  • Include knockout/knockdown controls if available

  • Consider using alternative antibody detection systems (fluorescent vs. chemiluminescent)

These systematic approaches should be documented in a troubleshooting matrix to identify the optimal combination of conditions that maximize specific signal while minimizing background.

How should researchers validate SPBC15C4.06c antibody specificity in the context of closely related S. pombe proteins?

Validating SPBC15C4.06c antibody specificity against potential cross-reactivity with related S. pombe proteins requires a comprehensive approach:

• Bioinformatic analysis for potential cross-reactivity:

  • Conduct sequence similarity searches (BLAST) using the immunogen sequence

  • Identify S. pombe proteins with similar domains, especially other RING finger proteins

  • Analyze sequence alignments to predict potential cross-reactive epitopes

• Genetic approach to validation:

  • Test antibody reactivity in wild-type versus SPBC15C4.06c deletion strains

  • Create strains with altered expression levels (overexpression, repressible promoters)

  • Use epitope-tagged versions of SPBC15C4.06c and related proteins for comparison

• Biochemical specificity validation:

  • Perform peptide competition assays with:

    • Specific peptides derived from SPBC15C4.06c

    • Similar peptides from related proteins

  • Express recombinant fragments of SPBC15C4.06c and related proteins for Western blot comparison

  • Conduct immunoprecipitation followed by mass spectrometry to identify all proteins captured by the antibody

• Advanced specificity controls:

  • Use orthogonal detection methods (e.g., antibodies targeting different epitopes)

  • Employ siRNA/RNAi to reduce expression and confirm signal reduction

  • Perform immunodepletion experiments to remove specific antibody reactivity

This systematic validation approach ensures that signals detected with the SPBC15C4.06c antibody genuinely represent the target protein rather than related RING finger proteins or other membrane proteins in S. pombe.

How can SPBC15C4.06c antibody be adapted for super-resolution microscopy to study membrane protein organization?

Adapting SPBC15C4.06c antibody for super-resolution microscopy requires specific modifications and considerations:

• Antibody labeling strategies for super-resolution techniques:

  • For STORM/PALM:

    • Direct conjugation with photoswitchable fluorophores (e.g., Alexa Fluor 647, Cy5)

    • Use of labeled secondary antibodies with appropriate buffer systems

  • For STED:

    • Conjugation with STED-compatible dyes (e.g., STAR dyes, Atto dyes)

    • Optimization of laser power to minimize photodamage

  • For Expansion Microscopy:

    • Use antibodies compatible with expansion protocols

    • Test retention of antibody binding after expansion

• Sample preparation optimization:

  • Evaluate different fixation methods (4% PFA, methanol, or glutaraldehyde)

  • Test mild detergent permeabilization protocols to maintain membrane integrity

  • Consider embedding in specialized resins for improved ultrastructure preservation

  • Optimize antigen retrieval methods specific for membrane proteins

• Controls and validation for super-resolution imaging:

  • Use SPBC15C4.06c-fluorescent protein fusions as references

  • Include knockout controls to establish background signal

  • Perform dual-labeling with established membrane compartment markers

  • Validate findings with complementary techniques (e.g., electron microscopy)

• Quantitative analysis approaches:

  • Develop cluster analysis protocols to quantify protein organization

  • Implement nearest-neighbor analysis for co-localization studies

  • Use pair-correlation functions to characterize spatial distributions

  • Apply machine learning approaches for pattern recognition in complex distributions

This methodological framework enables researchers to visualize SPBC15C4.06c organization at nanoscale resolution, providing insights into its membrane distribution and potential functional domains that cannot be resolved by conventional microscopy.

What considerations are important when developing high-throughput screening assays using SPBC15C4.06c antibody to identify regulators of its function?

Developing high-throughput screening assays using SPBC15C4.06c antibody requires careful design and validation:

• Assay format selection and optimization:

  • In-cell Western/cytoblot in 96/384-well format for measuring protein levels

  • High-content imaging to assess localization and expression simultaneously

  • ELISA-based approaches for quantifying protein modifications

  • Proximity-based assays (HTRF, AlphaScreen) to monitor protein-protein interactions

• Screening library considerations:

  • Kinase/phosphatase inhibitor libraries if post-translational modifications are of interest

  • S. pombe deletion/overexpression collections for genetic screens

  • Small molecule libraries targeting membrane proteins or trafficking

  • CRISPR libraries for targeted functional genomics

• Validation and quality control measures:

  • Develop robust positive and negative controls

  • Establish Z' factor >0.5 for assay quality

  • Implement plate normalization strategies

  • Design confirmation assays for hit validation

• Data analysis and integration approaches:

  • Multiparametric analysis for phenotypic screens

  • Machine learning for complex phenotype recognition

  • Network analysis to position hits in cellular pathways

  • Integration with existing datasets on S. pombe genetic interactions

This structured approach enables the systematic identification of factors regulating SPBC15C4.06c expression, localization, modification, or function, potentially revealing new insights into membrane protein biology in S. pombe.

How can researchers adapt immunoprecipitation protocols with SPBC15C4.06c antibody for identifying RNA-protein interactions?

Adapting SPBC15C4.06c antibody for RNA immunoprecipitation (RIP) requires specialized protocols that preserve RNA-protein interactions:

• Modified immunoprecipitation protocol:

  • Implement UV crosslinking (254 nm) or chemical crosslinking (formaldehyde) to stabilize RNA-protein interactions

  • Use RNase inhibitors throughout all buffer preparations

  • Modify lysis conditions to maintain RNA integrity:

    • Low-detergent buffers (0.1-0.5% NP-40 or Triton X-100)

    • Add RNase inhibitors (40-100 U/mL)

    • Include RNase-free BSA (0.1-0.5 mg/mL) as carrier

  • Perform all procedures at 4°C to minimize RNase activity

• RNA extraction and analysis workflow:

  • After immunoprecipitation with SPBC15C4.06c antibody:

    • Divide sample for protein (Western blot) and RNA analysis

    • Extract RNA using TRIzol or specialized RNA isolation kits

    • Verify RNA quality using bioanalyzer or gel electrophoresis

  • RNA identification options:

    • RT-PCR for candidate RNAs

    • RNA-seq for unbiased identification

    • qRT-PCR for quantitative analysis of specific transcripts

• Critical controls for RNA-IP experiments:

  • Input RNA sample (pre-immunoprecipitation)

  • IgG isotype control immunoprecipitation

  • RNA immunoprecipitation from SPBC15C4.06c deletion strain

  • RNase treatment control to confirm RNA-dependency of interactions

  • Immunoprecipitation of known RNA-binding proteins as positive controls

• Validation and functional characterization:

  • Confirm direct binding using:

    • Electrophoretic mobility shift assay (EMSA)

    • RNA pull-down with biotinylated RNA

    • In vitro binding assays with recombinant protein

  • Functional validation through:

    • Mutation of putative RNA-binding regions

    • Assessing RNA stability and localization in SPBC15C4.06c mutants

This approach allows researchers to explore potential RNA regulatory functions of SPBC15C4.06c, which might be unexpected for a RING finger membrane protein but could represent a novel functional aspect.