OR2T2/OR2T35 Antibody

What are OR2T2 and OR2T35 proteins, and why are they studied?

OR2T2 and OR2T35 are olfactory receptors belonging to the G-protein-coupled receptor (GPCR) family. These proteins contain seven transmembrane domains and are involved in detecting environmental odors, initiating neuronal responses that trigger smell perception. Research on these receptors helps understand sensory perception mechanisms, olfactory dysfunction, and general GPCR signaling pathways. These proteins are encoded by single coding-exon genes, with OR2T2 identified by UniProt ID Q6IF00 and OR2T35 by Q8NGX2 . Studying these receptors contributes to our understanding of how the brain processes olfactory stimuli and may have implications for treating sensory disorders.

What applications are OR2T2/OR2T35 antibodies validated for?

OR2T2/OR2T35 antibodies have been validated for multiple research applications including:

• Western Blot (WB) at dilutions of 1:500-1:3000

• Immunohistochemistry (IHC) for tissue sections

• Immunofluorescence/Immunocytochemistry (IF/ICC) at dilutions of 1:100-1:500

• ELISA at dilutions of 1:1000-1:10000

The optimal dilutions should be determined experimentally for each specific application and sample type. Validation data from multiple suppliers shows successful detection in human cell lines including HT29, HUVEC, HepG2, and A549 .

What is the molecular weight of OR2T2/OR2T35 proteins in Western blot analysis?

The calculated molecular weight of OR2T2/OR2T35 is approximately 34-36 kDa. When performing Western blot analysis, researchers should expect to detect bands around this size . The specific molecular weight may vary slightly depending on post-translational modifications and the particular isoform being detected. For accurate results, positive controls should be included in experimental design to verify the correct band identification.

How should OR2T2/OR2T35 antibodies be stored for optimal performance?

For maximum stability and performance, OR2T2/OR2T35 antibodies should be:

• Shipped at 4°C

• Aliquoted upon receipt to minimize freeze-thaw cycles

• Stored at -20°C for long-term preservation

• Avoid repeated freeze-thaw cycles which may cause protein degradation and loss of activity

• Stored in buffer containing PBS (pH 7.4), 150mM NaCl, 0.02% sodium azide, and 50% glycerol

Working aliquots can be kept at 4°C for short periods (1-2 weeks), but should be returned to -20°C for longer storage intervals.

What cell lines are most appropriate for studying OR2T2/OR2T35 expression?

Based on validation data from multiple antibody suppliers, these cell lines have demonstrated detectable levels of OR2T2/OR2T35 expression:

• HT29 colorectal adenocarcinoma cells

• HUVEC (Human Umbilical Vein Endothelial Cells)

• HepG2 hepatocellular carcinoma cells

• A549 lung adenocarcinoma cells

When selecting cell lines for your research, consider that expression levels may vary based on culture conditions and passage number. It's advisable to verify expression in your specific cell system using RT-PCR prior to antibody-based experiments.

How can I validate the specificity of OR2T2/OR2T35 antibodies in my experimental system?

To validate antibody specificity for OR2T2/OR2T35, implement these strategies:

• Peptide competition assay: Pre-incubate the antibody with the immunizing peptide before application to samples. Signal elimination or significant reduction confirms specificity .

• Positive and negative controls:

  • Use cell lines with known expression (HT29, HUVEC) as positive controls

  • Include non-expressing cell lines or knockdown/knockout systems as negative controls

• Molecular weight verification: Confirm that detected bands match the expected 34-36 kDa size

• Multiple antibody approach: Use antibodies raised against different epitopes of OR2T2/OR2T35 to confirm findings

• Correlation with mRNA expression: Compare protein detection with RT-PCR data from the same samples

Including these validation steps in your experimental design will substantially increase confidence in your findings.

What are the recommended blocking conditions for Western blots using OR2T2/OR2T35 antibodies?

For optimal Western blot results with OR2T2/OR2T35 antibodies:

• Block membranes with 5% non-fat dry milk or 3-5% BSA in TBST (Tris-buffered saline with 0.1% Tween-20) for 1 hour at room temperature

• For phospho-specific applications, BSA is preferred over milk as blocking agent

• When using OR2T2/OR2T35 antibodies, dilute in fresh blocking buffer at the recommended dilutions (typically 1:500-1:3000)

• Incubate with primary antibody either overnight at 4°C or for 2 hours at room temperature, depending on signal optimization

• After primary antibody incubation, wash thoroughly with TBST (at least 3×10 minutes) before adding appropriate secondary antibody

These conditions may require optimization based on your specific experimental setup and antibody lot.

How can I distinguish between OR2T2 and OR2T35 proteins in my samples given their sequence similarity?

Distinguishing between OR2T2 and OR2T35 presents a significant challenge due to their high sequence homology. Consider these approaches:

• Epitope mapping: Most commercial antibodies recognize both proteins because they target conserved regions. Check the immunogen information - antibodies raised against C-terminal regions may offer better discrimination as this region shows more variability .

• Isoform-specific regions: The protein sequences show that OR2T2 (Q6IF00) is 196 amino acids, while OR2T35 (Q8NGX2) is 322 amino acids. The additional C-terminal sequence in OR2T35 could be targeted for specific detection .

• High-resolution techniques:

  • 2D gel electrophoresis may separate the proteins based on subtle charge or size differences

  • Mass spectrometry analysis following immunoprecipitation can identify unique peptides

  • Specific RT-PCR assays can be used to correlate with protein expression

• Genetic approaches: CRISPR/Cas9 knockout of one isoform can help confirm antibody specificity and distinguish signals

No current commercial antibodies claim to exclusively detect only one of these proteins, so researchers should use complementary molecular biology approaches for definitive isoform identification.

What are the key considerations when performing immunofluorescence with OR2T2/OR2T35 antibodies?

For successful immunofluorescence experiments with OR2T2/OR2T35 antibodies:

• Fixation protocol optimization:

  • 4% paraformaldehyde (10-15 minutes) preserves protein epitopes while maintaining cellular architecture

  • Alternative fixatives like methanol or acetone may better expose certain epitopes

  • Test multiple fixation methods if initial results are unsatisfactory

• Permeabilization considerations:

  • OR2T2/OR2T35 are transmembrane proteins requiring careful permeabilization

  • Use 0.1-0.3% Triton X-100 or 0.1% saponin depending on epitope accessibility

  • Overly harsh permeabilization may disrupt membrane structure and epitope integrity

• Signal amplification strategies:

  • Tyramide signal amplification can enhance detection of low-abundance receptors

  • Secondary antibody selection impacts sensitivity (Alexa Fluor dyes offer superior photostability)

  • Dilution optimization (typically 1:100-1:500 for primary antibody)

• Controls:

  • Include peptide competition controls

  • Use known expressing cell lines as positive controls

  • Include secondary-only controls to assess background fluorescence

• Colocalization studies:

  • OR2T2/OR2T35 should colocalize with markers of the plasma membrane and potentially the endoplasmic reticulum

  • Consider double staining with organelle markers to confirm subcellular localization

Validation data from suppliers shows successful IF detection in A549 cells, making this a good starting point for protocol optimization .

What strategies can address non-specific binding when using OR2T2/OR2T35 antibodies?

Non-specific binding is a common challenge with OR2T2/OR2T35 antibodies. Implement these strategies to improve specificity:

• Antibody titration: Test multiple dilutions (beyond manufacturer recommendations) to find optimal signal-to-noise ratio

• Enhanced blocking protocols:

  • Extend blocking time to 2 hours or overnight

  • Add 0.1-0.3% Triton X-100 to blocking buffer to reduce hydrophobic interactions

  • Consider specialized blocking agents like fish gelatin or commercial blockers for challenging applications

• Additives to reduce background:

  • Add 5% normal serum from the secondary antibody host species

  • Include 0.1-0.5 M NaCl to disrupt low-affinity interactions

  • Consider adding 0.01-0.1% SDS to primary antibody dilution for Western blots

• Sample-specific considerations:

  • For tissue samples, include avidin/biotin blocking steps if using biotin-based detection

  • Pre-absorb antibodies with acetone powder from non-relevant tissues

• Wash optimization:

  • Increase wash duration and number (5×10 minutes instead of 3×5 minutes)

  • Add 0.05-0.1% Tween-20 to wash buffers

  • Consider high-salt washes (0.5 M NaCl) for stubborn background

Peptide competition assays provide the gold standard for distinguishing specific from non-specific signals, as demonstrated in validation data where antibody pre-incubation with immunizing peptide eliminated specific bands .

How should I interpret multiple bands in Western blots using OR2T2/OR2T35 antibodies?

When Western blots show multiple bands with OR2T2/OR2T35 antibodies, consider these interpretations and verification approaches:

• Expected band (34-36 kDa): Represents the monomeric form of OR2T2/OR2T35

• Higher molecular weight bands (70-75 kDa): May indicate:

  • Receptor dimerization (common in GPCRs)

  • Post-translational modifications (glycosylation, ubiquitination)

  • Incomplete denaturation of protein complexes

• Lower molecular weight bands (15-25 kDa): Potential:

  • Proteolytic degradation products

  • Alternative splice variants

  • Cross-reactivity with related olfactory receptors

Verification strategies:

• Peptide competition should reduce all specific bands

• Sample preparation modifications (stronger denaturing conditions, protease inhibitors)

• Alternative antibody targeting different epitope for confirmation

• Mass spectrometry analysis of excised bands

Without peptide competition controls, distinguishing between specific and non-specific signals remains challenging.

What are the potential causes for weak or absent signal when using OR2T2/OR2T35 antibodies?

When experiencing weak or absent signals with OR2T2/OR2T35 antibodies, systematically address these potential causes:

• Protein expression issues:

  • OR2T2/OR2T35 expression may be cell type-specific or condition-dependent

  • Verify mRNA expression by RT-PCR before protein analysis

  • Consider using positive control lysates (HT29, HUVEC, HepG2)

• Technical factors:

  • Antibody concentration: Try higher concentrations (1:250-1:500)

  • Incubation time: Extend to overnight at 4°C

  • Detection system sensitivity: Switch to more sensitive methods (ECL Prime, Femto)

  • Signal amplification: Consider biotin-streptavidin systems or tyramide signal amplification

• Sample preparation issues:

  • Protein extraction method: Membrane proteins require specialized lysis buffers with detergents

  • Loading amount: Increase protein loading (50-80 μg/lane)

  • Protein transfer efficiency: Optimize transfer conditions for membrane proteins

  • Fixation/permeabilization: Adjust for optimal epitope accessibility in IF/ICC

• Antibody-specific considerations:

  • Epitope accessibility: Certain fixation methods may mask epitopes

  • Lot-to-lot variability: Request validation data for specific lot

  • Storage conditions: Improper storage may reduce activity

Validation of these antibodies in specific cell lines provides starting points for troubleshooting experiments .

How can I differentiate between OR2T2/OR2T35 and other olfactory receptors with similar sequences?

Differentiating OR2T2/OR2T35 from other closely related olfactory receptors requires a multi-faceted approach:

• Sequence alignment analysis:

  • Identify unique sequence regions that distinguish OR2T2/OR2T35 from related receptors

  • Check antibody epitope against other OR family members using BLAST

  • The C-terminal region of OR2T2/OR2T35 shows greater variability and may provide better specificity

• Experimental verification strategies:

  • Recombinant protein controls expressing only OR2T2/OR2T35

  • Genetic approaches: siRNA knockdown to confirm signal reduction

  • CRISPR/Cas9 knockout validation

  • Heterologous expression systems with individual OR constructs

• Mass spectrometry approaches:

  • Immunoprecipitation followed by mass spectrometry can identify specific peptides

  • Parallel reaction monitoring (PRM) can quantify specific unique peptides

  • Targeted proteomics approaches focusing on discriminating peptides

• Complementary molecular techniques:

  • RNA-Seq data to correlate with protein expression

  • Subtype-specific RT-PCR primers

  • In situ hybridization with specific probes as correlative evidence

Most commercial antibodies cannot distinguish between very similar OR family members, so researchers should acknowledge this limitation and use complementary approaches for definitive identification.

What are appropriate positive and negative controls for OR2T2/OR2T35 immunohistochemistry in tissue samples?

For rigorous OR2T2/OR2T35 immunohistochemistry experiments, implement these control strategies:

Positive tissue controls:

• Olfactory epithelium: The natural expression site for many olfactory receptors

• Testis: Reported to express various olfactory receptors including OR family members

• Cell line-derived xenografts: HT29 or A549 xenografts based on validated expression

Negative tissue controls:

• Tissues with verified absence of OR2T2/OR2T35 expression

• Skeletal muscle: Generally shows low expression of olfactory receptors

• OR2T2/OR2T35 knockout tissues (if available)

Procedural controls:

• Peptide competition: Pre-absorption with immunizing peptide

• Antibody concentration gradients to determine optimal dilution

• Isotype control: Non-specific rabbit IgG at the same concentration

• Secondary-only controls: Omitting primary antibody

• Chromogen controls: Evaluating endogenous peroxidase blocking

Methodology validation:

• Parallel RNA in situ hybridization for OR2T2/OR2T35 mRNA

• Correlation with RT-PCR data from the same tissue regions

• Dual staining with markers of olfactory neurons or other cell types expressing the receptors

These comprehensive controls help distinguish true signal from artifacts and validate biological significance of immunostaining patterns.

How can OR2T2/OR2T35 antibodies be used in co-immunoprecipitation studies to identify interaction partners?

For successful co-immunoprecipitation (Co-IP) studies with OR2T2/OR2T35 antibodies:

• Sample preparation optimization:

  • Use mild lysis buffers containing 1% NP-40 or 1% digitonin to preserve protein-protein interactions

  • Include protease/phosphatase inhibitor cocktails to prevent degradation

  • Maintain cold temperature (4°C) throughout to preserve interactions

  • Pre-clear lysates with Protein A/G beads to reduce non-specific binding

• Antibody selection considerations:

  • Confirm antibody works in native conditions (not just denatured proteins)

  • Use antibodies targeting different epitopes for confirmation

  • Consider epitope tagging OR2T2/OR2T35 (e.g., FLAG, HA) for cleaner IP if antibody efficiency is low

• Technical optimization strategies:

  • Cross-linking approaches (DSP, formaldehyde) may stabilize transient interactions

  • Detergent screening (CHAPS, digitonin, DDM) for optimal membrane protein solubilization

  • Titrate antibody amount (typically 2-5 μg per mg total protein)

  • Optimize incubation time (overnight at 4°C is standard)

• Controls:

  • IgG control from same species as primary antibody

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

  • Reverse IP with antibodies against suspected interaction partners

  • Peptide competition to demonstrate specificity

• Verification of identified interactions:

  • Mass spectrometry analysis of co-precipitated proteins

  • Western blot confirmation of specific partners

  • Proximity ligation assay for in situ confirmation

  • Functional studies to validate biological relevance

Since OR2T2/OR2T35 are GPCRs, expect interactions with G-proteins, β-arrestins, and components of intracellular trafficking machinery.

What considerations are important when using OR2T2/OR2T35 antibodies in flow cytometry experiments?

When designing flow cytometry experiments with OR2T2/OR2T35 antibodies, address these key considerations:

• Cell preparation protocol:

  • Fixation: 2-4% paraformaldehyde preserves structure while allowing permeabilization

  • Permeabilization: 0.1% saponin or 0.1-0.3% Triton X-100 for intracellular domains

  • OR2T2/OR2T35 contains both extracellular and intracellular domains; protocol selection depends on epitope location

• Antibody validation for flow cytometry:

  • Most commercial OR2T2/OR2T35 antibodies are not explicitly validated for flow cytometry

  • Preliminary testing with known positive cells (HT29, A549) is essential

  • Titration experiments (1:50-1:500 dilutions) to determine optimal concentration

  • Signal-to-noise optimization with various blocking agents

• Controls design:

  • Isotype control: Rabbit IgG at equivalent concentration

  • Fluorescence-minus-one (FMO) controls

  • Peptide competition controls

  • Positive and negative cell lines

• Multi-parameter considerations:

  • Select fluorophores based on instrument configuration

  • Consider indirect detection with fluorophore-conjugated secondary antibodies for signal amplification

  • Include markers for cell typing/gating strategies

  • Dead cell exclusion dyes to eliminate false positives

• Data analysis approaches:

  • Histogram overlays comparing specific staining to controls

  • Mean fluorescence intensity (MFI) quantification

  • Correlation with other markers of interest

Although flow cytometry is not among the commonly listed applications for OR2T2/OR2T35 antibodies, careful optimization may yield successful results, particularly for surface-exposed epitopes.

How can OR2T2/OR2T35 antibodies contribute to research on ectopic expression of olfactory receptors in non-olfactory tissues?

Olfactory receptors, traditionally associated with olfactory epithelium, are increasingly recognized for their ectopic expression and potential functions in non-olfactory tissues. OR2T2/OR2T35 antibodies can advance this emerging research area:

• Tissue expression profiling:

  • Systematic IHC screening across tissue microarrays

  • Correlation with transcriptomic databases (GTEx, Human Protein Atlas)

  • Quantitative comparison of expression levels between tissues

  • Cell type-specific localization within heterogeneous tissues

• Functional investigation methods:

  • Co-localization with signaling molecules (adenylyl cyclase, phospholipase C)

  • Proximity ligation assays to detect protein interactions in situ

  • Activation-specific antibodies (if available) to monitor receptor engagement

  • Changes in OR2T2/OR2T35 expression during disease progression or treatment

• Disease-association studies:

  • Expression analysis in normal versus pathological samples

  • Correlation with clinical parameters and outcomes

  • Potential as biomarkers for specific conditions

  • Response to therapeutic interventions

• Mechanistic research approaches:

  • Ligand screening using OR2T2/OR2T35 as readouts

  • Signal transduction pathway mapping

  • Receptor trafficking and internalization studies

  • Integration with transcriptomic and proteomic data

These approaches could reveal novel functions of OR2T2/OR2T35 in diverse physiological processes beyond olfaction, contributing to our understanding of sensory receptor biology and potential therapeutic applications.

What methodological approaches can detect post-translational modifications of OR2T2/OR2T35 proteins?

Investigating post-translational modifications (PTMs) of OR2T2/OR2T35 requires specialized approaches:

• PTM-specific detection strategies:

  • Phosphorylation: Anti-phosphoserine/threonine/tyrosine antibodies following immunoprecipitation

  • Glycosylation: Lectin blotting, PNGase F treatment to assess glycosylation contribution to molecular weight

  • Ubiquitination: Anti-ubiquitin antibodies after OR2T2/OR2T35 immunoprecipitation

  • Palmitoylation: Acyl-biotin exchange chemistry followed by streptavidin detection

• Mass spectrometry approaches:

  • Enrichment strategies for specific PTMs (TiO₂ for phosphopeptides, lectin affinity for glycopeptides)

  • Multiple fragmentation methods (CID, ETD, HCD) for comprehensive PTM characterization

  • Targeted MS methods (PRM, MRM) for quantification of specific modified peptides

  • Top-down proteomics to analyze intact protein with modifications

• Functional investigation methods:

  • Site-directed mutagenesis of predicted modification sites

  • Pharmacological inhibitors of specific PTM enzymes

  • Correlation between modification status and receptor localization/function

  • FRET/BRET biosensors to monitor dynamic modifications

• Bioinformatic prediction and validation:

  • PTM prediction algorithms for phosphorylation, glycosylation, etc.

  • Structural modeling to assess impact of modifications on receptor conformation

  • Evolutionary conservation analysis of potential modification sites

  • Integration with known GPCR modification patterns

Understanding the PTM landscape of OR2T2/OR2T35 would provide insights into receptor regulation, trafficking, and signaling dynamics.

How can OR2T2/OR2T35 antibodies be adapted for super-resolution microscopy techniques?

Adapting OR2T2/OR2T35 antibodies for super-resolution microscopy requires specialized considerations:

• Primary antibody optimization for super-resolution compatibility:

  • Validation of specificity at higher concentrations often needed for single-molecule detection

  • Testing different antibody clones/lots for optimal performance

  • OR2T2/OR2T35 are membrane proteins, requiring careful protocol optimization

  • Peptide competition controls are essential to confirm specificity at the nanoscale level

• Technique-specific adaptations:

  • STORM/PALM: High-quality secondary antibodies conjugated to photoswitchable fluorophores (Alexa Fluor 647, Atto 488)

  • STED: Secondary antibodies with STED-compatible fluorophores (STAR RED, ATTO 647N)

  • SIM: Bright, photostable fluorophores and careful refractive index matching

  • DNA-PAINT: DNA-labeled secondary antibodies for exchange imaging

• Sample preparation considerations:

  • Fixation optimization to preserve nanoscale architecture

  • Membrane-specific permeabilization protocols (digitonin for selective permeabilization)

  • Drift correction strategies (fiducial markers)

  • Appropriate buffers for specific techniques (oxygen scavenging for STORM)

• Quantitative analysis approaches:

  • Cluster analysis of receptor distribution

  • Colocalization with other signaling components at nanoscale resolution

  • Single-particle tracking with photoactivatable fluorophores

  • Correlative approaches with functional imaging (calcium indicators)

• Biological applications:

  • Nanoscale organization of OR2T2/OR2T35 in membrane microdomains

  • Conformational changes upon ligand binding

  • Receptor internalization and trafficking dynamics

  • Oligomerization and interaction with signaling complexes

These advanced imaging approaches could reveal unprecedented details about OR2T2/OR2T35 organization and dynamics in cellular membranes.

What considerations are important when developing multiplexed detection systems that include OR2T2/OR2T35 antibodies?

Developing multiplexed detection systems incorporating OR2T2/OR2T35 antibodies presents several technical challenges and opportunities:

• Antibody compatibility considerations:

  • Host species deconfliction: Select OR2T2/OR2T35 antibodies from hosts different from other target antibodies

  • Isotype differentiation: Utilize different isotypes for secondary antibody discrimination

  • Cross-reactivity testing: Validate absence of cross-reactivity between antibodies in multiplex panel

  • Titration in multiplex context: Optimal concentrations may differ from single-plex applications

• Detection system adaptations:

  • Fluorescent multiplex: Select spectrally distinct fluorophores with minimal overlap

  • Chromogenic multiplex: Sequential detection with complete stripping between rounds

  • Mass cytometry: Metal-conjugated antibodies for high-parameter analysis

  • Sequential fluorescence: Cyclic immunofluorescence with antibody stripping or quenching

• Technical optimization strategies:

  • Blocking optimization to minimize background in complex panels

  • Signal balancing for targets with widely different expression levels

  • Order of antibody application testing (simultaneous vs. sequential)

  • Validation with single-stain controls and FMO approaches

• Analytical approaches:

  • Spectral unmixing for overlapping fluorophores

  • Background subtraction algorithms for autofluorescence

  • Colocalization analysis with appropriate controls

  • Hierarchical clustering of expression patterns

• Biological applications:

  • Co-expression analysis with other olfactory receptors

  • Signaling pathway component relationships

  • Cell type identification based on receptor patterns

  • Correlation with functional outcomes in heterogeneous populations

These multiplexed approaches enable systems-level analysis of OR2T2/OR2T35 biology in complex tissues and heterogeneous cell populations.

Methodological Table: Recommended Protocols for OR2T2/OR2T35 Antibody Applications