YBR287W Antibody

What is YBR287W and why would researchers need antibodies against it?

YBR287W is an uncharacterized transporter protein found in Saccharomyces cerevisiae (baker's yeast). The protein localizes to the endoplasmic reticulum (ER) and belongs to the auxin efflux carrier (TC 2.A.69) family, containing 427 amino acids . Although classified as a non-essential gene, its study is valuable for understanding membrane transport mechanisms and protein-protein interactions in yeast cellular pathways. Antibodies against YBR287W are crucial research tools for detecting, quantifying, and characterizing this protein in various experimental contexts.

How do YBR287W antibodies compare to other yeast protein detection methods?

When comparing detection methods:

Antibody-based detection: Provides specific protein localization and quantification capabilities through techniques like Western blotting, immunofluorescence, and immunoprecipitation.

GFP-fusion approaches: While GFP-fusion proteins allow live-cell imaging of YBR287W (as noted in the protein description ), they may alter protein function or localization.

Mass spectrometry: Offers higher sensitivity for detecting low-abundance proteins but requires specialized equipment and sample preparation. YBR287W has been detected in proteomic studies examining Cyc8p and Tup1p regulation .

RNA-based methods: qPCR can measure YBR287W transcript levels but doesn't provide information about post-transcriptional regulation or protein stability.

The choice depends on the specific research question, with antibodies offering the advantage of detecting native protein without genetic modification.

What resources are available for finding validated YBR287W antibodies?

Researchers should consider multiple sources when searching for YBR287W antibodies:

• Commercial antibody catalogs: Companies like Cusabio offer YBR287W antibodies (CSB-PA336442XA01SVG, targeting P38355) .

• Antibody search engines: Platforms like CiteAb and Antibodypedia allow comparative searches across vendors . These tools help researchers find antibodies with experimental validation data.

• Data repositories: Resources sharing validation and experimental data for antibodies, such as:

  • The Human Protein Atlas

  • Antibody Registry

  • Antibodypedia

  • Addgene's antibody validation data (though currently only accepts data for antibodies in their repository)

• Literature references: Publications demonstrating successful use of YBR287W antibodies in specific applications provide valuable validation information.

What are the recommended protocols for using YBR287W antibodies in chromatin immunoprecipitation (ChIP) experiments?

While specific protocols for YBR287W ChIP are not widely established, researchers can adapt standard yeast ChIP protocols with the following considerations:

• Crosslinking: Formaldehyde treatment (typically 1% for 10-15 minutes) to crosslink protein-DNA complexes in yeast cells grown to mid-log phase (OD600 0.5-0.7) .

• Cell lysis: Disrupt cells using bead-beating (5 cycles of 1 minute each at 4°C) in lysis buffer containing protease inhibitors .

• DNA shearing: Sonicate lysates (4 cycles of 30 seconds each, power setting 5, 50% duty cycle) to generate DNA fragments of 300-1000 bp .

• Immunoprecipitation: Incubate sheared chromatin with YBR287W antibody (typically 2-5 μg) for at least 4 hours at 4°C, followed by Protein G-Sepharose beads for 2 additional hours .

• Washing and elution: Perform stringent washes to remove non-specific binding, then elute bound complexes.

• Crosslink reversal and DNA purification: Heat samples to reverse crosslinks, treat with proteinase K, and purify DNA.

• Analysis: Analyze by qPCR or sequence the immunoprecipitated DNA to identify binding regions.

How can YBR287W antibodies be used in colocalization studies with translocon complex proteins?

Given YBR287W's ER localization and predicted functional partnership with SSH1 (score 0.922) , colocalization studies could reveal important insights:

• Sample preparation:

  • Fix yeast cells with 4% paraformaldehyde

  • Perform spheroplasting using zymolyase

  • Permeabilize with appropriate detergent

• Dual immunofluorescence protocol:

  • Primary antibodies: Use YBR287W antibody alongside antibodies against SSH1 or other translocon components (ensure they're raised in different species)

  • Secondary antibodies: Use spectrally distinct fluorophore-conjugated antibodies

  • Include DAPI staining for nuclear visualization

• Imaging considerations:

  • Confocal microscopy with z-stack acquisition for 3D reconstruction

  • Super-resolution techniques (SIM, STORM) for detailed ER structures

  • Quantitative colocalization analysis using Pearson's or Mander's coefficients

• Controls:

  • Single antibody controls to verify specificity

  • Secondary-only controls to assess background

  • Known ER markers as positive controls

What considerations should be made when designing immunoprecipitation experiments with YBR287W antibodies?

When designing co-immunoprecipitation experiments to investigate YBR287W interactions:

• Buffer optimization:

  • Consider testing multiple lysis buffers (e.g., HEPES-based buffer with 150mM potassium chloride, 1mM EDTA, 10% glycerol, and 0.1% Nonidet P-40)

  • Include appropriate protease inhibitors to prevent degradation

  • For membrane proteins like YBR287W, mild detergents (0.5-1% NP-40 or Triton X-100) can help solubilize without disrupting interactions

• Antibody selection:

  • Use antibodies validated for immunoprecipitation

  • Consider epitope accessibility in the native protein conformation

• Experimental controls:

  • Input controls (5-10% of starting material)

  • IgG negative controls

  • Reciprocal IPs with antibodies against predicted interaction partners

• Verification methods:

  • Western blot analysis of immunoprecipitates

  • Mass spectrometry for unbiased interaction partner identification

• Potential interaction partners to investigate:

  • SSH1 (translocon complex component)

  • CKI1 (choline kinase)

  • YHC3 (vacuolar membrane protein)

  • Other predicted functional partners from STRING analysis

How can yeast display technologies be adapted to generate high-affinity antibodies against YBR287W?

Yeast display offers powerful approaches for generating and optimizing antibodies against challenging targets like membrane proteins:

• Library construction:

  • Create diverse antibody fragment (scFv/nanobody) libraries in yeast surface display vectors

  • PCR-amplify variable regions and clone into display vectors via gap repair

• Selection strategy:

  • Express recombinant YBR287W with purification tags

  • Perform selection rounds using magnetic bead sorting or flow cytometry

  • Apply stringent washing to isolate high-affinity binders

  • Consider microfluidic approaches with controlled shear rates (168-926 1/s) to balance specificity and recovery

• Affinity maturation:

  • Introduce mutations via error-prone PCR

  • Create targeted libraries focusing on complementarity-determining regions

  • Perform increasingly stringent selections to isolate higher-affinity variants

• Conversion to biobodies:

  • Transfer selected binders to secretion vectors with biotin acceptor sites

  • Co-express with biotin ligase (BirA) in diploid yeast

  • Harvest in vivo biotinylated antibodies from culture supernatants

• Validation:

  • Confirm binding by ELISA, surface plasmon resonance

  • Test functionality in relevant applications

  • Compare affinity to commercially available antibodies

This approach has successfully generated antibodies with nanomolar affinities (e.g., 5.4×10⁻¹⁰ M and 2.6×10⁻⁹ M for model targets) .

What approaches can resolve cross-reactivity issues with YBR287W antibodies?

Cross-reactivity is a common challenge with yeast protein antibodies due to conserved domains and structural similarities:

• Epitope analysis and selection:

  • Identify unique regions of YBR287W with low homology to other proteins

  • Target epitopes outside the conserved auxin efflux carrier domain

  • Consider computational epitope prediction tools to identify antigenic regions

• Antibody engineering techniques:

  • Use negative selection strategies during antibody development

  • Perform alanine scanning mutagenesis to identify residues affecting specificity

  • Apply directed evolution with counterselection against close homologs

• Validation approaches:

  • Test against YBR287W knockout controls

  • Perform peptide competition assays

  • Evaluate reactivity across multiple applications

  • Use complementary detection methods (mass spectrometry)

• Purification strategies:

  • Affinity purification against the immunizing peptide

  • Negative purification against cross-reactive proteins

  • Sequential adsorption to remove antibodies recognizing common epitopes

• Application-specific solutions:

  • For Western blotting: Use higher dilutions and shorter exposure times

  • For immunofluorescence: Include additional blocking agents and optimize fixation

How can researchers investigate potential post-translational modifications of YBR287W using antibody-based methods?

Investigating post-translational modifications (PTMs) of YBR287W requires specialized approaches:

• PTM-specific antibody development:

  • Generate antibodies against predicted phosphorylation, glycosylation, or ubiquitination sites

  • Use synthetic peptides containing the modified residue as immunogens

  • Validate specificity using site-directed mutagenesis controls

• Enrichment strategies:

  • Perform immunoprecipitation with YBR287W antibodies followed by PTM-specific detection

  • Use phospho-enrichment techniques (TiO₂, IMAC) prior to analysis

  • Consider two-step IP protocols to increase sensitivity

• Detection methods:

  • Western blotting with PTM-specific antibodies

  • Mass spectrometry analysis of immunoprecipitated material

  • Phos-tag SDS-PAGE for phosphorylation detection

• Experimental designs:

  • Compare PTM status under different growth conditions

  • Examine PTM changes during stress responses

  • Investigate PTM dynamics during the yeast cell cycle

• Functional validation:

  • Generate phospho-mimetic or phospho-dead mutants

  • Perform complementation assays

  • Assess interaction profile changes upon modification

What are common challenges in generating reliable Western blot results with YBR287W antibodies?

Researchers should consider these specific challenges when blotting for YBR287W:

• Protein extraction optimization:

  • As a membrane protein, YBR287W requires effective solubilization

  • Test different detergents: RIPA, NP-40, Triton X-100, or specialized membrane protein extraction buffers

  • Consider using spheroplasting methods for yeast cells

• Transfer conditions:

  • Optimize transfer time and voltage for efficient transfer of membrane proteins

  • Consider semi-dry vs. wet transfer systems

  • For difficult transfers, test specialized methods like CAPS buffer or methanol gradients

• Blocking optimization:

  • Test different blocking agents (BSA vs. milk) as milk may contain phosphatases that could affect phosphoprotein detection

  • Optimize blocking time and temperature

• Signal detection:

  • Start with higher antibody concentrations (1:500) and titrate down

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

  • Use enhanced chemiluminescence or fluorescent secondary antibodies for higher sensitivity

• Controls:

  • Include YBR287W knockout/negative control

  • Use loading controls appropriate for membrane proteins (e.g., Na⁺/K⁺-ATPase)

  • Consider recombinant YBR287W as a positive control

• Troubleshooting:

  Problem	Possible Causes	Solutions
  No signal	Poor extraction, inefficient transfer, inactive antibody	Try harsher extraction methods, optimize transfer, test new antibody lot
  Multiple bands	Cross-reactivity, protein degradation, PTMs	Increase washing stringency, add protease inhibitors, validate with knockout controls
  High background	Insufficient blocking, non-specific binding	Increase blocking time, add Tween-20 to washes, reduce antibody concentration

How can researchers optimize immunofluorescence protocols for detecting YBR287W in yeast cells?

Immunofluorescence for yeast membrane proteins requires specific optimization:

• Cell wall digestion:

  • Optimize zymolyase treatment time (typically 30-60 minutes)

  • Monitor spheroplast formation microscopically

  • Use osmotic stabilizers to prevent cell lysis

• Fixation methods:

  • Compare formaldehyde (3-4%) vs. methanol/acetone fixation

  • For membrane proteins, mild fixation often preserves epitope accessibility

  • Consider dual fixation protocols for both structure and antigenicity preservation

• Permeabilization:

  • Test different concentrations of Triton X-100 (0.1-0.5%)

  • Consider digitonin for selective plasma membrane permeabilization

  • Optimize time and temperature

• Antibody incubation:

  • Higher primary antibody concentrations (1:50-1:200) are often needed

  • Extended incubation times (overnight at 4°C)

  • Include BSA and normal serum in antibody dilution buffer

• Colocalization markers:

  • Include ER markers (e.g., antibodies against Sec61 or Kar2)

  • Consider DAPI staining for nuclear visualization

  • Use known interaction partners like SSH1 as colocalization references

• Imaging considerations:

  • Z-stack acquisition for complete cell visualization

  • Deconvolution to improve signal-to-noise ratio

  • Airyscan or other super-resolution techniques for detailed ER structure

What strategies exist for validating YBR287W antibody specificity in research applications?

Comprehensive validation ensures reliable experimental results:

• Genetic validation:

  • Test against YBR287W knockout strains

  • Use strains with tagged YBR287W (HA, FLAG, or GFP tags)

  • Compare signal between wild-type and overexpression systems

• Biochemical validation:

  • Peptide competition assays to verify epitope specificity

  • Preabsorption tests with recombinant YBR287W

  • Immunoprecipitation followed by mass spectrometry

  • Western blot verification of molecular weight and band pattern

• Orthogonal validation methods:

  • Compare antibody results with GFP-fusion localization data

  • Correlate protein detection with mRNA expression levels

  • Use CRISPR-Cas9 to create epitope deletions

• Cross-application validation:

  • Confirm consistent results across different techniques (Western, IF, IP)

  • Test under various experimental conditions

  • Evaluate performance in fixed vs. live cell applications

• Documentation and reporting:

  • Record batch-to-batch variation

  • Document all validation experiments

  • Consider submitting validation data to antibody repositories

How does YBR287W relate to stress response pathways in yeast, and how can antibodies help investigate this?

Understanding YBR287W's role in stress responses can be facilitated through antibody-based approaches:

• Expression level analysis:

  • Track YBR287W protein levels during various stresses (heat shock, oxidative stress, nutrient deprivation)

  • Compare with known stress-responsive proteins

  • Examine if YBR287W is regulated by heat shock factor (HSF) or other stress-response transcription factors

• Localization changes:

  • Investigate whether cellular distribution changes during stress

  • Monitor potential movement between ER subdomains

  • Examine co-localization with stress response proteins

• Post-translational modifications:

  • Analyze stress-induced phosphorylation or other modifications

  • Compare PTM status before and after stress exposure

  • Investigate if modifications affect transporter function

• Interaction partners:

  • Identify stress-specific interaction partners through co-IP

  • Examine if predicted partners (SSH1, CKI1, YHC3) show altered interactions during stress

  • Compare with interaction networks of known stress-responsive proteins

• Experimental approaches:

  • Time-course experiments following stress induction

  • Chromatin immunoprecipitation to identify transcription factor binding

  • Quantitative Western blotting to measure expression changes

What methodological approaches can investigate potential functional relationships between YBR287W and its predicted interaction partners?

To explore YBR287W's functional relationships with predicted partners like SSH1 (translocon complex), CKI1 (choline kinase), and YHC3 (vacuolar membrane protein) :

• Co-immunoprecipitation studies:

  • Perform reciprocal pulldowns with antibodies against YBR287W and partner proteins

  • Use crosslinking approaches to stabilize transient interactions

  • Analyze by Western blotting or mass spectrometry

• Proximity labeling approaches:

  • Create BioID or APEX2 fusions with YBR287W

  • Identify proteins in close proximity through biotinylation

  • Compare proximal proteins under different conditions

• Genetic interaction analysis:

  • Create single and double mutants of YBR287W and partner genes

  • Quantify genetic interactions through growth phenotypes

  • Measure synthetic lethality or suppression effects

• Functional assays:

  • Measure transport activities in single and double mutants

  • Assess ER function and stress response in mutant combinations

  • Analyze phosphatidylcholine synthesis in YBR287W/CKI1 mutants

• Structural studies:

  • Use antibody fragments for co-crystallization

  • Perform cross-linking mass spectrometry to map interaction interfaces

  • Employ FRET/BRET approaches to measure in vivo interactions

• Data integration:

  Method	Application	Expected Output
  Co-IP with YBR287W antibody	Protein complex identification	Confirmation of physical interactions
  ChIP-seq	Transcriptional regulation	Shared regulatory mechanisms
  Quantitative proteomics	Expression correlation	Co-regulated protein networks
  Fluorescence microscopy	Colocalization analysis	Spatial relationship in cells

How might advances in antibody engineering technologies improve YBR287W research?

Emerging antibody technologies offer new opportunities for studying this uncharacterized transporter:

• Single-domain antibodies (nanobodies):

  • Smaller size enables access to cryptic epitopes within membrane proteins

  • Potential for intracellular expression ("intrabodies") to track YBR287W in living cells

  • Can be displayed on yeast surface for directed evolution

• Bispecific antibodies:

  • Target YBR287W alongside interaction partners simultaneously

  • Create proximity-inducing antibodies to study protein-protein interactions

  • Develop detection systems with dual specificity and enhanced signal

• Antibody fragments with specialized properties:

  • Develop Fab or scFv fragments optimized for specific applications

  • Create in vivo biotinylated antibodies (biobodies) using yeast secretion systems

  • Engineer pH or redox-sensitive antibodies for compartment-specific detection

• CRISPR-based epitope tagging:

  • Integrate small epitope tags recognized by well-characterized antibodies

  • Create conditional tagging systems for regulated detection

  • Develop split-tag systems to study protein-protein interactions

• Antibody-based biosensors:

  • Create FRET-based sensors to detect conformational changes

  • Develop antibody-based reporters for transporter activity

  • Design antibody-conjugated nanoparticles for single-molecule tracking

What are the most significant knowledge gaps regarding YBR287W that antibody-based research could address?

Critical knowledge gaps that targeted antibody research could help resolve:

• Functional characterization:

  • YBR287W is predicted to be a transporter, but its substrates remain unknown

  • Antibodies could help purify the protein for in vitro transport assays

  • Blocking antibodies could provide insights into functional domains

• Regulatory mechanisms:

  • How YBR287W expression and localization are regulated remains unclear

  • Antibodies could track protein levels and distribution under different conditions

  • ChIP studies could identify transcription factors controlling expression

• Protein-protein interactions:

  • Predicted interactions with SSH1, CKI1, and others need verification

  • Co-IP with YBR287W antibodies could identify true interaction partners

  • Proximity labeling approaches could map the interaction network

• Structural information:

  • The three-dimensional structure remains unresolved

  • Antibodies could be used for structural studies (cryo-EM, X-ray crystallography)

  • Epitope mapping could provide insights into accessible domains

• Physiological significance:

  • While non-essential, YBR287W's conservation suggests functional importance

  • Antibodies could help determine if it participates in specific cellular processes

  • Quantitative studies could reveal condition-specific expression patterns