SPBC1E8.03c Antibody

What is SPBC1E8.03c and what is its significance in fission yeast research?

SPBC1E8.03c is a protein found in Schizosaccharomyces pombe (fission yeast), identified with UniProt accession number O42968. It is primarily studied in fission yeast models, which are valuable for understanding fundamental cellular processes. Fission yeast serves as an excellent model organism for studying various cellular mechanisms due to its genetic tractability and similarity to human cells in many basic cellular processes .

The corresponding antibody against SPBC1E8.03c is particularly useful for researchers working with S. pombe strain 972/ATCC 24843, as it has been specifically raised against recombinant protein from this strain. Understanding this protein's function can contribute to broader knowledge about cellular pathways in eukaryotes, potentially relating to human disease mechanisms .

What are the optimal storage conditions for maintaining SPBC1E8.03c antibody activity?

The SPBC1E8.03c antibody should be stored at either -20°C or -80°C immediately upon receipt. It's crucial to avoid repeated freeze-thaw cycles as these can significantly reduce antibody activity and specificity. The antibody is supplied in a liquid form with a storage buffer containing 0.03% Proclin 300 as a preservative, 50% glycerol, and 0.01M PBS at pH 7.4 .

For researchers planning long-term storage, aliquoting the antibody into smaller volumes before freezing is recommended to minimize freeze-thaw cycles. When working with the antibody, keep it on ice and return it to -20°C or -80°C as soon as possible after use.

What is the species reactivity profile of the SPBC1E8.03c antibody?

The SPBC1E8.03c antibody has been specifically developed to react with Schizosaccharomyces pombe (strain 972/ATCC 24843), also known as fission yeast. This strain specificity is important to note when designing experiments, as cross-reactivity with other yeast strains or species has not been extensively characterized .

The antibody is a rabbit polyclonal IgG that has been affinity purified against the antigen. When considering experimental design, it's essential to account for this species specificity, particularly if working with multiple yeast species or strains.

What applications has the SPBC1E8.03c antibody been tested for?

The SPBC1E8.03c antibody has been tested and validated for two primary applications:

• ELISA (Enzyme-Linked Immunosorbent Assay): Useful for quantitative detection of the target protein in solution.

• Western Blot (WB): Enables visualization of the target protein in cell or tissue lysates, providing information about protein expression levels and molecular weight .

When designing experiments with this antibody, researchers should consider that these are the validated applications. Use in other applications such as immunohistochemistry (IHC), immunofluorescence (IF), or immunoprecipitation (IP) may require additional optimization and validation.

How should Western blot protocols be optimized for SPBC1E8.03c antibody?

When optimizing Western blot protocols for the SPBC1E8.03c antibody, consider the following methodological approach:

• Sample Preparation:

  • Use appropriate lysis buffers for fission yeast (typically containing protease inhibitors)

  • Ensure complete cell disruption through methods like glass bead lysis

  • Centrifuge to remove cell debris and quantify protein concentration

• Gel Electrophoresis:

  • Use 10-12% SDS-PAGE gels for optimal separation

  • Load 20-40 μg of total protein per lane

  • Include molecular weight markers

• Transfer and Blocking:

  • PVDF membranes often provide better results than nitrocellulose for yeast proteins

  • Block with 5% non-fat dry milk in TBST for 1 hour at room temperature

• Antibody Incubation:

  • Start with 1:1000 dilution in blocking buffer and optimize as needed

  • Incubate overnight at 4°C for primary antibody

  • Use anti-rabbit HRP-conjugated secondary antibody at 1:5000 dilution

• Detection:

  • Enhanced chemiluminescence (ECL) detection systems work well

  • Exposure times may need optimization based on protein abundance

What positive and negative controls should be used with SPBC1E8.03c antibody?

For rigorous experimental design, include the following controls:

Positive Controls:

• Lysates from wild-type S. pombe strain 972/ATCC 24843 expressing the target protein

• Recombinant SPBC1E8.03c protein (if available)

• Samples with known overexpression of the target protein

Negative Controls:

• Lysates from S. pombe strains with SPBC1E8.03c gene deletion or knockdown

• Secondary antibody only (no primary antibody) to assess non-specific binding

• Pre-immune serum control to evaluate background

• Blocking peptide competition assay to confirm specificity

How can epitope mapping be performed for SPBC1E8.03c antibody?

Epitope mapping for the SPBC1E8.03c antibody can be accomplished through several methodological approaches:

• Peptide Array Analysis:

  • Synthesize overlapping peptides (typically 15-20 amino acids long with 5-10 amino acid overlaps) spanning the entire SPBC1E8.03c protein sequence

  • Immobilize peptides on a membrane or microarray

  • Probe with the antibody and detect binding using secondary antibody

  • Identify specific peptide regions that show reactivity

• Deletion Mutant Analysis:

  • Generate a series of truncated SPBC1E8.03c proteins

  • Express these proteins recombinantly

  • Perform Western blot analysis to determine which fragments retain antibody binding

  • Narrow down the epitope region through iterative deletion mapping

• Site-Directed Mutagenesis:

  • Once a general epitope region is identified, introduce point mutations

  • Assess changes in antibody binding affinity

  • Identify specific residues critical for antibody recognition

This approach is similar to methods used for other antibodies, such as the M0313 antibody against SEB where researchers identified specific binding regions like SEB 85-102 and key amino acids in positions 90-92 .

How can SPBC1E8.03c antibody be adapted for immunoprecipitation studies?

To adapt the SPBC1E8.03c antibody for immunoprecipitation studies:

• Antibody Immobilization:

  • Conjugate the antibody to Protein A/G beads or magnetic beads

  • Alternatively, use pre-conjugated anti-rabbit IgG beads and add the SPBC1E8.03c antibody

• Sample Preparation:

  • Prepare cell lysates under non-denaturing conditions

  • Use gentle lysis buffers (e.g., 50 mM Tris-HCl pH 7.5, 150 mM NaCl, 1% NP-40, 0.5% sodium deoxycholate, with protease inhibitors)

  • Clear lysates by centrifugation to remove debris

• Immunoprecipitation Protocol:

  • Pre-clear lysate with protein A/G beads to reduce non-specific binding

  • Incubate cleared lysate with antibody-conjugated beads (2-5 μg antibody per sample)

  • Wash extensively with buffer containing reduced detergent

  • Elute bound proteins using SDS sample buffer or low pH glycine buffer

• Analysis:

  • Analyze precipitated proteins by Western blot or mass spectrometry

  • Include IgG control to account for non-specific binding

  • Consider cross-linking antibody to beads to prevent antibody co-elution

What approaches can be used for studying protein-protein interactions involving SPBC1E8.03c?

Several methodological approaches can be employed to study protein-protein interactions:

• Co-Immunoprecipitation (Co-IP):

  • Use the SPBC1E8.03c antibody to pull down the target protein

  • Analyze co-precipitating proteins by Western blot or mass spectrometry

  • Confirm interactions by reciprocal Co-IP with antibodies against putative interacting partners

• Proximity Labeling:

  • Generate fusion proteins of SPBC1E8.03c with BioID or APEX2

  • Express in S. pombe and activate the enzyme to biotinylate nearby proteins

  • Purify biotinylated proteins and identify by mass spectrometry

• Yeast Two-Hybrid Screening:

  • Use SPBC1E8.03c as bait in a yeast two-hybrid screen

  • Screen against a fission yeast cDNA library

  • Validate positive interactions through other methods

• Fluorescence Resonance Energy Transfer (FRET):

  • Create fluorescent protein fusions with SPBC1E8.03c and potential interacting partners

  • Measure energy transfer between fluorophores when proteins interact

  • Quantify interaction dynamics in living cells

What are common causes of non-specific binding with SPBC1E8.03c antibody?

Non-specific binding can result from several factors:

• Insufficient Blocking:

  • Increase blocking time (1-2 hours)

  • Try alternative blocking agents (BSA, casein, commercial blocking buffers)

  • Add 0.1-0.3% Tween-20 to reduce hydrophobic interactions

• Suboptimal Antibody Concentration:

  • Test serial dilutions (1:500, 1:1000, 1:2000, 1:5000)

  • Find the optimal concentration that maximizes specific signal while minimizing background

• Cross-Reactivity Issues:

  • Pre-absorb the antibody with acetone powder from non-target species

  • Perform Western blots on negative control samples to identify cross-reactive bands

• Sample Preparation Problems:

  • Ensure complete protein denaturation for Western blots

  • Use fresh samples and avoid protein degradation

  • Include appropriate protease inhibitors in lysis buffers

How can I improve signal-to-noise ratio when using SPBC1E8.03c antibody?

To improve signal-to-noise ratio:

• Optimize Antibody Concentration:

  • Titrate the antibody to find the minimum concentration that gives detectable specific signal

  • Typical starting dilutions: 1:1000 for Western blot, 1:100 for immunofluorescence

• Adjust Incubation Conditions:

  • Extend primary antibody incubation (overnight at 4°C)

  • Increase washing steps (5-6 washes of 5-10 minutes each)

  • Consider using a more sensitive detection system (e.g., enhanced chemiluminescence)

• Optimize Buffer Composition:

  • Add 0.1-0.5% detergent (Tween-20, Triton X-100) to reduce background

  • Include 1-5% carrier protein (BSA, normal serum) in antibody dilution buffer

  • Try different blocking agents to reduce non-specific binding

• Signal Enhancement Techniques:

  • Use signal amplification systems (e.g., biotin-streptavidin)

  • Consider tyramide signal amplification for very low abundance proteins

  • Try different detection substrates with higher sensitivity

What should I do if SPBC1E8.03c antibody shows decreased reactivity over time?

If you observe decreased antibody reactivity:

• Storage Assessment:

  • Check storage conditions (-20°C or -80°C)

  • Minimize freeze-thaw cycles by storing in small aliquots

  • Add stabilizing proteins like BSA (0.1-1%) if not already present

• Buffer Optimization:

  • Check buffer pH and salt concentration

  • Add preservatives like sodium azide (0.02%) to prevent microbial growth

  • Consider adding glycerol (50%) for long-term storage

• Antibody Concentration:

  • Measure protein concentration to check for precipitation or degradation

  • Adjust antibody concentration in experiments to compensate for activity loss

• Replacement Considerations:

  • Note that the shelf life for research antibodies is typically 12-24 months

  • Order a new lot if significant activity loss is observed

  • Request lot-specific validation data from the supplier when ordering

What methods are recommended for validating SPBC1E8.03c antibody specificity?

To validate antibody specificity:

• Genetic Controls:

  • Test the antibody in wild-type vs. knockout/knockdown S. pombe strains

  • Observe disappearance of signal in samples lacking the target protein

• Overexpression Systems:

  • Compare antibody reactivity in cells with normal vs. overexpressed SPBC1E8.03c

  • Confirm increased signal intensity proportional to overexpression levels

• Peptide Competition Assay:

  • Pre-incubate antibody with excess purified antigen or immunizing peptide

  • Observe elimination of specific signal in Western blot or other applications

• Multiple Antibody Validation:

  • Compare results with other antibodies raised against different epitopes

  • Confirm consistent detection of the same protein

• Mass Spectrometry Verification:

  • Immunoprecipitate the target protein using the antibody

  • Confirm identity by mass spectrometry analysis

How can I assess lot-to-lot variability in SPBC1E8.03c antibody performance?

To assess lot-to-lot variability:

• Side-by-Side Testing:

  • Run parallel experiments with old and new antibody lots

  • Use identical samples, conditions, and detection methods

  • Compare signal intensity, specificity, and background

• Standard Sample Panel:

  • Maintain a set of standard positive and negative control samples

  • Test each new lot against these standards

  • Create a reference Western blot or ELISA result for comparison

• Quantitative Assessment:

  • Measure binding affinity using ELISA or surface plasmon resonance

  • Determine EC50 values for each lot

  • Compare titration curves to assess sensitivity differences

• Record Keeping:

  • Document lot numbers, dates received, and performance metrics

  • Maintain a laboratory database of antibody validation results

  • Note any observed differences in optimal working dilutions or protocols

The SPBC1E8.03c antibody is made-to-order with a lead time of 14-16 weeks, so advance planning for continuity in research projects is advised .

How does SPBC1E8.03c research relate to the broader field of yeast model systems?

Fission yeast (S. pombe) serves as an excellent model organism for studying fundamental cellular processes that are conserved across eukaryotes. Research involving SPBC1E8.03c contributes to our understanding of protein function in this model system.

Similar to studies with other yeast proteins, such as those involved in the TSC pathway (e.g., Tsc1, Tsc2, and Rhb1), research on SPBC1E8.03c can provide insights into conserved molecular mechanisms. For example, the TSC pathway research in fission yeast has revealed important insights about signaling cascades that may branch below Rhb1 (the fission yeast homolog of human RHEB), which has implications for understanding human disease mechanisms and drug efficacy .

What experimental approaches are recommended for studying protein localization using SPBC1E8.03c antibody?

For protein localization studies:

• Immunofluorescence Microscopy:

  • Fix S. pombe cells with 3.7% formaldehyde for 30 minutes

  • Permeabilize cell wall with zymolyase or lysing enzymes

  • Block with 1% BSA in PBS for 1 hour

  • Incubate with SPBC1E8.03c antibody (starting at 1:100 dilution)

  • Use fluorophore-conjugated secondary antibodies

  • Counterstain with DAPI to visualize nuclei

• Subcellular Fractionation:

  • Separate cellular components (nucleus, cytoplasm, membranes)

  • Analyze fractions by Western blot using the SPBC1E8.03c antibody

  • Compare distribution across fractions to determine localization

• Correlative Light and Electron Microscopy:

  • Perform immunogold labeling using SPBC1E8.03c antibody

  • Visualize ultrastructural localization using electron microscopy

  • Correlate with fluorescence microscopy data for comprehensive localization