OR5P3 Antibody

What is OR5P3 and what is its biological function?

OR5P3 (Olfactory Receptor Family 5 Subfamily P Member 3) is a G-protein-coupled receptor (GPCR) involved in olfactory signal transduction. It features a characteristic 7-transmembrane domain structure common to olfactory receptors and functions by interacting with odorant molecules in the nasal epithelium to initiate neuronal responses that trigger smell perception . OR5P3 plays a crucial role in the recognition and G protein-mediated transduction of odorant signals, contributing to the discriminatory capacity of the human olfactory system. The OR5P3 gene belongs to the olfactory receptor gene family, which is notably the largest gene family in the human genome .

What types of OR5P3 antibodies are available for research applications?

Several OR5P3 antibodies are available for research applications, each with specific characteristics:

For comprehensive OR5P3 research, additional tools include:

• OR5P3 ELISA Kit (ABIN1743624) with a detection range of 50-1000 pg/mL and sensitivity of 1.0 pg/mL

• Human OR5P3 (aa 178-200) Control Fragment Recombinant Protein for validation experiments

What is the molecular weight and structure of OR5P3, and how does this impact detection methods?

OR5P3 has a molecular weight of approximately 34 kDa as detected by Western blot analysis . Structurally, it is a G-protein-coupled receptor featuring the characteristic 7-transmembrane domain architecture typical of olfactory receptors . This membrane-embedded structure requires special consideration during experimental design.

The protein is encoded by a single coding-exon gene, which is characteristic of the olfactory receptor family . For antibody production and validation, several specific regions have proven immunogenic:

• Amino acids 55-104 (used for the A100876 antibody)

• Amino acids 178-200 (used for the control fragment recombinant protein)

• The sequence FCDYSPLLKLACSHDFTFEIIPA (used for the NBP2-32566 antibody)

These regions represent accessible epitopes important for antibody binding. When designing experiments, researchers should consider the membrane-embedded nature of OR5P3 and select sample preparation methods that effectively solubilize membrane proteins without disrupting antibody epitopes.

How should I optimize Western blot protocols for effective OR5P3 detection?

For optimal Western blot detection of OR5P3, follow these methodological recommendations:

Sample Preparation:

• Use lysis buffers containing detergents suitable for membrane protein extraction (e.g., NP-40, Triton X-100, or RIPA buffer with 0.1% SDS)

• Incorporate protease inhibitor cocktail to prevent degradation

• Sonicate briefly to shear genomic DNA and improve protein extraction

Gel Electrophoresis and Transfer:

• Load 20-50 μg of total protein per lane

• Use 10-12% SDS-PAGE gels for optimal resolution around the 34 kDa molecular weight of OR5P3

• For transmembrane proteins like OR5P3, semi-dry transfer with 10-15% methanol in transfer buffer often yields better results than wet transfer

Antibody Application:

• Block membranes with 5% non-fat dry milk or BSA in TBST

• Incubate with the anti-OR5P3 antibody A100876 at dilutions of 1:500-1:1000

• Extend primary antibody incubation to overnight at 4°C for improved signal quality

• Use appropriate HRP-conjugated secondary antibodies (e.g., Goat Anti-Rabbit IgG H&L Antibody)

Controls and Validation:

• Include positive control samples (e.g., COLO cells, which have demonstrated OR5P3 expression)

• Run a negative control lane where the primary antibody has been pre-absorbed with the blocking peptide

• For densitometric analysis, include housekeeping proteins as loading controls

Validation studies have demonstrated specificity of the A100876 antibody for OR5P3 in COLO cells with the expected band at approximately 34 kDa .

What are the optimal approaches for OR5P3 immunohistochemistry in different tissue types?

Optimizing immunohistochemistry protocols for OR5P3 requires tissue-specific considerations:

General Protocol Optimization:

• Use the Novus Biologicals rabbit polyclonal antibody (NBP2-32566) validated for IHC and IHC-P applications at 1:200-1:500 dilution

• For FFPE tissues, heat-induced epitope retrieval is essential; test both citrate buffer (pH 6.0) and Tris-EDTA buffer (pH 9.0)

• Employ a polymer-based detection system appropriate for rabbit primary antibodies

• Include antigen-blocking controls using the OR5P3 Control Fragment Recombinant Protein

Tissue-Specific Considerations:

Validation Approach:

• Include parallel sections with isotype control antibodies

• Perform peptide blocking by pre-incubating the antibody with 100x molar excess of the OR5P3 control fragment

• Compare staining patterns with mRNA expression data when available

• Document cellular localization pattern (membrane-associated for GPCRs)

For tissues with potential low OR5P3 expression, consider using amplification systems such as tyramide signal amplification or quantum dot-based detection to enhance sensitivity while maintaining specificity.

What are the key considerations for quantitative analysis of OR5P3 using ELISA?

ELISA provides a sensitive method for quantitative analysis of OR5P3. Consider these methodological aspects:

ELISA Kit Parameters (OR5P3 ELISA Kit ABIN1743624):

• Detection Method: Colorimetric competition ELISA

• Detection Range: 50-1000 pg/mL

• Minimum Detection Limit: 50 pg/mL

• Sensitivity: 1.0 pg/mL

• Compatible Sample Types: Cell culture supernatant, plasma, serum, tissue homogenate

Sample Preparation Guidelines:

• Process samples immediately after collection when possible

• For cell culture supernatant: Centrifuge at 3000 x g to remove cellular debris

• For plasma: Use EDTA or heparin as anticoagulant; avoid hemolyzed samples

• For tissue homogenates: Homogenize in cold PBS (pH 7.4), then centrifuge at 5000 x g

• Perform preliminary experiments to determine optimal sample dilution factors

Assay Optimization:

• Generate a standard curve using provided standards A through F

• Run all standards and samples in triplicate

• Follow exact incubation times and temperatures specified in the protocol

• Use a microplate reader capable of measuring absorbance at 450 nm

Data Analysis and Quality Control:

• For competition ELISA, signal intensity is inversely proportional to OR5P3 concentration

• Calculate intra-assay and inter-assay coefficients of variation (aim for <15%)

• Consider matrix effects on quantification

• Normalize results to total protein concentration when comparing different sample types

For custom ELISA development using Anti-OR5P3 Antibody A100876, a dilution of 1:10000 is recommended , but optimization for specific experimental conditions is advisable.

How can I validate the specificity of OR5P3 antibodies in my experimental system?

Comprehensive validation of OR5P3 antibody specificity is crucial for reliable research outcomes. Implement these complementary approaches:

Peptide Competition/Blocking Experiments:

• Pre-incubate the anti-OR5P3 antibody with the OR5P3 (aa 178-200) Control Fragment Recombinant Protein

• Use a 100x molar excess of the protein fragment based on antibody concentration and molecular weight

• Pre-incubate the mixture for 30 minutes at room temperature before application

• A significant reduction in signal indicates specificity for the target epitope

Multi-platform Validation:

• Compare results across different applications (e.g., IHC, WB, ELISA)

• Consistent detection of OR5P3 at the expected molecular weight (34 kDa) and cellular location across different methods supports specificity

Molecular Approaches:

• Implement siRNA knockdown of OR5P3 and assess signal reduction

• Use OR5P3 overexpression systems as positive controls

• Compare antibody-based detection with mRNA expression data

Cross-reactivity Assessment:

• The NBP2-32566 antibody has been verified for specificity against 383 non-specific proteins

• For novel experimental systems, consider testing against related olfactory receptors

• Be aware that the human OR5P3 (aa 178-200) region shows 87% sequence identity to mouse and rat orthologs, which may affect cross-species applications

A robust validation strategy should incorporate multiple approaches appropriate to your experimental system and research questions.

How do post-translational modifications affect OR5P3 antibody recognition?

Post-translational modifications (PTMs) can significantly impact antibody recognition of OR5P3:

Potential PTMs in OR5P3:

• As a GPCR, OR5P3 likely undergoes several modifications:

  • N-linked glycosylation at extracellular domains

  • Palmitoylation at cytoplasmic cysteine residues

  • Phosphorylation at serine/threonine residues in intracellular loops and C-terminus

  • Ubiquitination affecting receptor trafficking and degradation

Epitope Accessibility Considerations:

• The A100876 antibody targets amino acids 55-104 of human OR5P3

• The NBP2-32566 antibody recognizes the sequence FCDYSPLLKLACSHDFTFEIIPA

• PTMs near or within these epitopes may sterically hinder antibody binding

Experimental Approaches to Assess PTM Impact:

• Compare antibody recognition in native versus denatured conditions

• Employ enzymatic treatments (glycosidases, phosphatases) to remove specific PTMs

• Look for multiple molecular weight bands in Western blots that may represent differentially modified forms

• Use immunoprecipitation followed by mass spectrometry to characterize PTMs

Interpretive Considerations:

• The expected molecular weight of unmodified OR5P3 is 34 kDa

• Higher molecular weight bands may represent glycosylated forms

• Phosphorylation typically adds minimal weight but can alter protein migration

• Document which form(s) of OR5P3 are being detected in your experimental system

When investigating functional aspects of OR5P3, consider how PTMs might regulate receptor activity, trafficking, and signaling capabilities.

What are the methodological challenges in studying OR5P3 expression in non-canonical tissues?

While OR5P3 is primarily expressed in olfactory epithelium, investigating its potential expression in non-canonical tissues presents several methodological challenges:

Sensitivity and Specificity Tradeoffs:

• Expression levels in non-olfactory tissues may be orders of magnitude lower

• Increasing detection sensitivity often comes at the cost of increased background

• Ultra-sensitive methods require rigorous validation controls

Tissue-Specific Detection Strategies:

Technical Recommendations:

• For Western blot: Increase protein loading (50-100 µg), extend exposure times

• For IHC: Use high-sensitivity polymer detection systems, minimize background with specialized blocking

• For ELISA: Concentrate protein extracts before analysis, extend antibody incubation times

• For all methods: Include parallel analysis of mRNA expression

Interpretive Challenges:

• Distinguishing low-level specific signal from background

• Confirming biological relevance of detected expression

• Determining if detected protein is full-length and functional

• Establishing if expression patterns are consistent across individuals/samples

When reporting OR5P3 expression in non-canonical tissues, comprehensive validation with multiple detection methods and appropriate controls is essential to support confidence in findings.

What positive and negative controls should be used in OR5P3 antibody experiments?

Proper experimental controls are essential for reliable interpretation of OR5P3 antibody-based experiments:

Positive Controls:

Negative Controls:

Protocol for Peptide Blocking Control:

• Use a 100x molar excess of the protein fragment control based on antibody concentration

• Pre-incubate the antibody-protein control fragment mixture for 30 min at room temperature

• Run parallel experiments with blocked and unblocked antibody

• A significant reduction in signal indicates specific binding to the target epitope

For comparative studies across different tissues or experimental conditions, standardize all protocols and include all appropriate controls in each experimental set to ensure valid comparisons.

How do orthologous OR5P3 proteins differ between human and rodent models?

Understanding the differences between human OR5P3 and its rodent orthologs is crucial for translational research and antibody selection:

Sequence Homology Analysis:

• The human OR5P3 (aa 178-200) region shows 87% sequence identity to both mouse and rat orthologs

• This relatively high conservation suggests functional similarity across species

• The 7-transmembrane domain architecture characteristic of GPCRs is conserved between species

Antibody Cross-Reactivity Implications:

Experimental Design Considerations:

• When using human-reactive OR5P3 antibodies in rodent models:

  • Validate antibody specificity in rodent tissues using peptide competition assays

  • Include positive controls from human samples for comparison

  • Consider complementary detection methods (e.g., mRNA analysis)

  • If possible, use antibodies specifically validated for the species of interest

Functional Considerations:

• Despite high sequence homology, subtle differences may affect:

  • Ligand binding specificity

  • G-protein coupling efficiency

  • Receptor trafficking and localization

  • Response to regulatory mechanisms

When designing cross-species studies, these differences should be carefully considered in experimental design and data interpretation.

How can I troubleshoot weak or absent OR5P3 signals in Western blot applications?

When encountering weak or absent OR5P3 signals in Western blot experiments, consider these methodological troubleshooting approaches:

Sample Preparation Issues:

• Insufficient protein extraction: Use stronger lysis buffers containing 0.1% SDS or 0.5% sodium deoxycholate

• Protein degradation: Add fresh protease inhibitors immediately before lysis

• Inefficient solubilization: Extend incubation time with lysis buffer or include brief sonication steps

• Consider using specialized membrane protein extraction kits for GPCRs

Technical Parameters:

• Insufficient protein loading: Increase to 50-75 μg total protein per lane

• Transfer efficiency: Optimize transfer conditions for membrane proteins (adjust methanol percentage, transfer time)

• Primary antibody concentration: Test higher concentrations within the recommended range (1:250 instead of 1:1000)

• Secondary antibody selection: Ensure compatibility with primary antibody host species

• Detection system sensitivity: Switch to higher sensitivity ECL substrate for low abundance proteins

Membrane Treatment:

• Verify epitope accessibility: Test multiple antibodies targeting different epitopes

• Blocking optimization: Test alternative blocking agents (casein, commercial blockers)

• Extended antibody incubation: Increase primary antibody incubation to 24-48 hours at 4°C

• Reduce washing stringency: Decrease salt concentration or detergent percentage

Systematic Evaluation:

• Test antibody on positive control samples (e.g., COLO cells)

• Assess antibody functionality with dot blot of recombinant protein

• Verify protein transfer with reversible staining before antibody incubation

• Consider alternative antibodies if troubleshooting steps fail

When reporting results, clearly document optimization steps performed and include appropriate positive and negative controls.

What strategies can minimize cross-reactivity when working with OR5P3 antibodies?

Cross-reactivity is a significant concern when working with antibodies against olfactory receptors due to their sequence similarity within the family. Implement these strategies to minimize cross-reactivity:

Antibody Selection:

• Choose antibodies raised against unique regions of OR5P3

• The NBP2-32566 antibody has been verified for specificity on a protein array containing the target protein plus 383 other non-specific proteins

• Consider using monoclonal antibodies for higher specificity if available

Experimental Protocol Optimization:

• Increase antibody dilution beyond standard recommendations (e.g., 1:750 instead of 1:500)

• Optimize blocking conditions (consider testing different blocking agents: BSA, casein, commercial solutions)

• Add 0.1-0.5% non-ionic detergent (Triton X-100, Tween-20) to reduce hydrophobic interactions

• Increase wash duration and stringency (higher salt concentration)

• Reduce primary antibody incubation temperature (4°C instead of room temperature)

Validation Controls:

• Perform pre-absorption controls with the OR5P3 Control Fragment Recombinant Protein

• Use a 100x molar excess of the protein fragment based on antibody concentration

• Include tissue/cells known to lack OR5P3 expression as negative controls

• Consider testing the antibody against recombinant proteins of closely related olfactory receptors

Data Analysis and Interpretation:

• Examine staining patterns for consistency with expected subcellular localization

• Compare results across multiple detection methods

• Correlate protein detection with mRNA expression data when available

• Document and report any observed cross-reactivity in your experimental system

By implementing these strategies systematically, researchers can maximize specificity while maintaining sensitivity for OR5P3 detection.